Heads and Gaskets guidance
 

Hey everybody, I promise I tried the search function but I couldn't find anything so I'm posting this.

My beautiful 1984 928S blew a head gasket(s?) and is now blowing white smoke and barely has enough power to idle. Tomorrow I'll be confirming with a hydrocarbon test, but I need guidance on how to repair the damage. I've already decided on using the Graphite-Composite Steel head gaskets from 928 Motorsports, but that's about all I know. Is this a repair that I can do myself? I don't have a way of pulling the engine so if that has to be done I'll be putting it in storage until I can afford a mechanics fees. I'm assuming that this problem was caused by; overfilling the oil by about 1 quart, and overheating a few times (pegged the red because I'm retarded). Could I have done any un-repairable damage? if so, how could I diagnose?

The pre-failure symptoms were

* over-heating due to failure to move coolant properly caused by
- PO removing the T-stat
- Air gaps in radiator hoses
- non-functioning auxillary fan
* one of the cylinders not firing after engine warmed up (would fire and run smoothly again after turning the car off and restarting)

Now to when it happened. I had just gotten back from a short drive to pay closer attention to what happened directly before the one cylinder stopped firing. The temp gauge hit the second mark right as I parked it in the garage. After I parked it I put the e-brake on and the Trans in neutral to check ATF levels. After I checked the ATF level I got back in the car to turn it off. Then I popped the hood and started squeezing the radiator lines to try to massage some of the air pockets out which I could hear was working. After I got done with that I hopped in and re-started the car (it started idling smoothly on all cylinders after that) and no more than 30 seconds later I heard the auxiliary fan kick in, and watched the temp gauge drop from the second mark to the first mark, and then a few seconds later it started pouring bellows of white smoke out of the exhaust. It still idled on all cylinders (if you left it idling for about 2 minutes it would start running smoothly again) after it was bellowing white smoke, but it scared me ****less so I shut it off.

So I'm also wondering if the auxiliary fan working again had anything to do with it? I also noticed that the fog lights started working again after that (I'm assuming that it was relay failure?). I also need to know what parts I'm going to need, if I can do this repair with the engine still in the car, and if there is a detailed guide on doing this? I really just need any guidance that you guys are willing to give me. I'm a college student so I have a very limited budget, but I'm very mechanically inclined (I used to own a lot of vintage motorcycles and I rebuilt the engines on most of them. I also did a lot of work on an MG Midget I owned before the porsche) so if I don't have to pull the engine I know this is something I could do myself, but again, I really need guidance; this is my first time owning a porsche.

Thank you in advanced for any help!

If you don't have the 928 Workshop Manuals, here they are online. I believe they are pdf's, so you can save them.

http://www.2010.cannell.co.uk/manual...s_porsche.html

Here are two links which may be helpful.

https://rennlist.com/forums/928-foru...ferrerid=34007

https://rennlist.com/forums/928-foru...r+head+removal

You will most likely need to pull the engine, you can do it with the engine still in the car but there is basically no room, so yes you will regret doing that. There are two lift points on the engine to help with removal. Buy an engine hoist and stand (they cost less than the mechanic) and do it your self. There are plenty of other jobs to do like the timing belt and water pump and various gaskets to replace while they are easy to get to. Have the engine deck and heads checked for flatness too, the overheating could have in the worst case, warped your engine beyond repair. Good luck with the repair.

MP; You have absolutely no idea how hard I've been looking for those manuals!! Thankyou so much. I downloaded all of the different sections (I think I have about 3000 pages of information to read now haha)

TFO; I don't want to pull the engine because I don't really have the means to do that. Is there not any way that I could remove the fenders or something instead? That seems a lot more feasible for my situation.

I wish you well with this job. Knock on wood, I've never had to pull the engine up to this point but I have done quite a bit else. Some of the Masters will chime in to help with this job.

The hard part will be getting the cam housings off, after that the heads aren't too bad to get off, just remember the heads use studs and not bolts. You WILL struggle to get the cam housings off as there is little room and removing the fenders doesn't add any room or access to the engine. Keep track of removing parts as some are hard to get a hold of and replace all consumable items being removed. Good luck with the repair.

What led you to making that parts selection?

Have you ever changed a head gasket on any car? Are you confident in you abilities to pull this off? I think you are better off using stock style had gaskets.

I have never changed a head gasket on a car, but plenty of motorcycles, and there was a first for those too (got it right the first time). The reason I'm going with the graphite composite steel gaskets is because it has a fire ring made with modern, more reliable, tougher materials and processes. I just don't see why I would use a stock gasket designed and produced with materials and technologies from 1984 (almost 30 years old!) when I could put something a little bit more modern and reliable in it.

If it ain't broke, I'll fix it 'til it is

Thee ole college spirit !
Lazer, take heed to what some of the Masters say about 928 matters before you dive in.

Pull the motor, it will be easier in the long run.

I can not pull the motor. I either fix it myself with the motor in, or a pay for somebody else to do it, which would mean putting the car in storage for a few months til I can afford it.

If it ain't broke, I'll fix it 'til it is

Can not and will not are different. A hoist is way cheaper than paying a mechanic.

Maybe he lives in an apartment, and only has 1 space? Make a friend who has a garage?

Lazer,
Here's some good transmission pdf's if you ever need them. Hopefully you won't.

http://www.w124performance.com/docs/...2_Mitchell.pdf

http://www.w124performance.com/docs/...722_repair.pdf

I'm in the midst of doing this exact same thing on my 84 auto. First time for me too.

https://rennlist.com/forums/928-foru...l#post10722471

I only have a single car garage and thus have very limited space, so I pulled the engine up, pushed the car out onto the driveway, and then put the engine down and on a stand. I'm actually about to go into the garage to try and clean off these damn cam tower gaskets. What a bitch to get off, my goodness. I'll probably spend all day doing this, maybe more.

I can't really comment on how difficult it would be to remove the heads with the engine in the car, but I can only imagine it would be quite a pain, especially if you've never done it before and don't know what hidden bolts you are looking for. That being said, it apparently can be done. I need to replace my motor mounts and oil pan gasket and give the engine a good cleaning as well, so pulling the motor made the most sense in my case. It's not terribly difficult to do either...if I can do it, anyone can, and that's not false modesty. I can pass along a checklist of things to disconnect. It took me about three evenings to complete, and I am a slow working noob.

I'll be doing this probably next winter myself....I want to refresh it, and clean the engine compartment and prep for paint.

The factory head gaskets are very good at what they do. There is nothing wrong with their fire rings or the materials they are made from. It held up for 30 years, isn't that enough. There are engines with some really nice HP that still use OEM gaskets with zero issues.

you should pull the engine then refresh the engine.

Buy a Victor Reinz full engine gasket set,
also get a silicone pan gasket and a new Laso waterpump.

NOTE your going to be into this repair for about 2000.00 ,
with all of the parts and the machine shop work , and you doing all the work
make sure the heads get magnafluxed for cracks

Did you read the "Read this First" sticky yet? The reason I ask is because there are links to the WSM downloads in it. Links to a lot of other helpful and useful info too.

Why can't you pull the motor? No space? Nowhere secure to keep it?
"Don't have the means" doesn't say much.

Unbolt everything, get it ready to pull. Rent or borrow a hoist for a day. Buy a stand.

Far, far cheaper than paying someone else.

And if you go back to page 2, you will find this:

https://rennlist.com/forums/928-foru...ggestions.html

Head gasket on an 84. He has decided to pull the motor. It has a lot of useful stuff.

Another one is this:

https://rennlist.com/forums/928-foru...r-warning.html

It's not a head gasket, it's TBF and bent valves. But it's about pulling the heads with the motor in the car. Lots of pics, lots of useful stuff.

Edit to add: While I was composing this, Simon chimed in. He's the first thread I linked (the one on page 2).

I took a video today of the car, I was moving it to a more covered area before I do the work to clear out the cylinders, when I noticed it was performing and acting a lot better than it had been. Here's the video, let me know what you guys think
If it ain't broke, I'll fix it 'til it is

To be honest the smoke is looking a lot less like coolant and a lot more like oil smoke (similar to my old two stroke bikes) and it smells like uncooked bread dough, kinda yeast-y maybe? I'm not trying to convince myself that it isn't the heads but none of the problems are being consistent.

If it ain't broke, I'll fix it 'til it is

Lazer,
A question.
Does your oil have coolant in it, or does your coolant have oil ?

Also, if you have ATF leaking by the cats you need to address that for safety reasons.

MP; I know that the ATF is flammable and I've read the stories of cars catching fire from neglected leaks down there, so that will be the next thing I fix. I have a great hydraulic shop I. Town I'll take them too. Also, there are little spots of what appear to be oil in the coolant resevoir, now that you mention it. Why?

If it ain't broke, I'll fix it 'til it is

Defect in the oil cooler ?
or
Head gasket as you suspect.

If there's oil in the coolant or coolant in the oil, why would it be smoking? Neither one should be in the cylinder right?

If it ain't broke, I'll fix it 'til it is

You'll know it's coolant because your coolant level will be dropping. Coolant in a cylinder leaves a plug very white, as it's being steam-cleaned.


Do a compression test on the engine and see which cylinder is leaking if any. If you aren't familiar (you should be with motorcycle experience), do the test with all plugs out and throttle propped open, fuel pump and ignition fuses pulled.

Do a leakdown test with each cylinder at TDC. The leakdown test lets you listen to see where the test air is going. You'll notice the air coming out through the coolant bottle if theres a leakage path there, otherwise intake and/or exhaust and/or crankcase noises tell you about where it's leaky.


If you decide that the engine needs internal work, pull the engine and put it on a stand where you can work on it. There's plenty to do and there's hardly any room to work with the engine in the car. Some might brag that they did a head gasket with the engine in place, but I can tell you from experience that it's a ton of extra work trying to do it in place. Lots of opportunity for collateral damage to the car. You'll have the chance to properly clean everything so less risk of contamination. You'll be able to inspect things too.

----

Head gaskets don't just blow on these cars without some related issues. Getting the engine hot enough to warp a head and cause gasket failure means the head is likely warped. There are known longer-term issues with cooling system maintenance and corrosion that can contribute, and require repair or rework of heads and block to replace missing metal. The bores are critical, and if they are scored or out of round much, the rework costs can easily exceed the value of the car.

You mention that you'd have to save up for repairs, so I'll warn you now that you are heading down a very slippery slope on 928 parts and possibly labor costs. There's a JB mantra that says that "you are ten thousand dollars away from having a five thousand dollar car", and that applies to folks who find a car that's reasonably sound to start with. When I look at a 928 for someone, I start off with a $5k number for replacement of rubber and other known age-related wear items needed to make any 928 safe and reliable enough to drive. That's just the parts budget, and it probably needs to be revised up some. Then deduct for stuff that's been replaced recently. Again, assumes a car that's otherwise mechanically sound. So think carefully about the costs in dollars and time that will be needed to make the car 'right', at least to the point where you would be willing to own and drive it. I preach that the cheapest 928 to own is the one that's perhaps the most expensive to buy, the one where the loving owner has been religious about maintenance care. Unless you cherish the restoration and repair work as therapy (as I sometimes do), you should consider letting this car go as it is, and finding the 'right' car when your budget allows.

If it's ATF you should get red drips at other times and ATF should run down the hose and lines and you should see ATP coating the lines and heat shields in that area. The "white smoke" looks like it's steam leaking out of the exhaust. You should be able to determine if that is so or it is external. Also, if the AC is on, the evaporator box drains exactly in that area above the cats, but you will hear "drip/sizzle" with any external fluid leak onto the cats when you turn off the motor and the steam is not constant as yours appears but intermittent with each drip.

It's common for head gasket leaks to vary depending on engine temp and stress.

I am running factory head gasket at 700 rwhp on an S4 and it's not failing. I think you can find bigger problems with the motor, if the 16V motor has the same kind of gasket.

I think we need a definitive description on what the smoke smells like if it smells sweet then its coolant if it smells like oil then it could be oil getting sucked into the intake from a misrouted hose or you have a lots of blowby from the rings a compression test will confirm this

The smoke smells more like oil, not sweet at all. My first thought when I smelled it was that it smelled like raw bread dough.

If it ain't broke, I'll fix it 'til it is

you would be wise to remove the plugs take a picture and post it,
then do a compression test,
then remove the aircleaner and inspect the intake for oil puddles,
you may be sucking oil into the intake and not have a HG issue.
but rather a water pump /thermostat issue.

It would also be a good idea to get another 928 mechanic to look at your car,
as misdiagnosis will only cause you to fix something that may not be broken,
we can only do so much on guessing ,
the more info you provide adds to the diagnosis being closer to correct for your situation

Sure looks like coolant to me. Easy test: is the coolant level dropping and are there any shiny/white/wet spark plugs.

I'll pull the Plugs tomorrow night, but could you please explain the water pump/thermostat theory to me? That would make sense because I seriously doubt the water pump is moving coolant, and that I got the correct thermostat, but yesterday the aux fan kicked on like it started moving water over the sensor finally, but then today, it's not smoking nearly as much, and the aux fan isn't coming again, and I don't feel any current when I squeeze the rad-hoses. I would just like to understand that theory a little more is all. A new water pump and tstat housing rebuild would be a cheap thing to try before pulling the engine, and it needs both either way. And again, it's not entirely white, it a light grey (I know the pictures don't show that) and it reminds me more of my two stroke bikes than steam.

If it ain't broke, I'll fix it 'til it is

Are the radiator hoses getting wam/hot? If both the upper and lower hoses yo the rafiator are getting warm/hot then you are moving water.

Please follow to the letter what I posted in post 32,
after you do that please post the results of what you found .

NOTE you keep asking for answers and provide no information on what has already been suggested to do,
if you wont follow these directions it will become a cat chasing its tail repair procedure,
and nothing will be diagnosed and or fixed properly

Alright, so I'm on my lunch break right now, and I just checked the coolant and oil, and there's definitely plenty of coolant in the oil; the coolant was about a quart lower, and the oil is now about a quart over the max fill line, and very watery (dripping off of the dipstick) I'm kinda scared that this means cracked block?? Please tell me this is something less catastrophic! Also, the top line is hot when it's running, and the bottom line is warm, but definitely not hot. Any ideas on what this means? I'll do run down and compression tests as soon as I can buy the tools, but until then I'm hoping we can make some sense of the symptoms I just described?

If it ain't broke, I'll fix it 'til it is

Mrmerlin, I will be doing the tests and following your instructions, but I've been working all weekend and the soonest I'll be able to buy the necessary tooling will be Tuesday, until then I'm trying to gather as much information and possible problems as I can so I know everything I can do to diagnose things on Tuesday. I'm sorry if dealing with me is frustrating but I really do appreciate all of the information and tips you guys are giving me.

If it ain't broke, I'll fix it 'til it is

Can anybody explain the water pump theory, or why I have a quart of coolant in my sump? Again, I'm not looking for definitive answers or solutions, I'm looking for as many possible things that could be causing my problems, so that on Tuesday I can buy all the tools I need and do all of the proper testing. I'm just trying to provide as much information as I possibly can with the time I have to work on the car.

If it ain't broke, I'll fix it 'til it is

Is'nt there a good supply of used 16 valve engines out there? Maybe consider saving up and buying a parts car that has a known good running engine?

There are a lot of cars out there for $1-2K and engines for the same or less. You just have to look around. I love in the northeast and I found 10 within 250 miles of me in that category. Heck I bought a complete running 5 speed euro shark for $2k and picked up another engine and 5 speed for $650.

The coolant in the oil seals the deal -- You have blown a headgasket and/or a cracked head or block. The lubrication for the cams in the heads is passed through ports in the same head gasket the coolant passes through. If the gasket fails between the coolant passage and an oil drain, then coolant will flow through failed section.

The heads and block are aluminum, and are very sensitive to coolant quality. Most coolants slowly change pH as they age in the block, turning acidic over time. Some have buffers in them to extend the time. Most coolants need to changed annually to be sure that the effects are minimized. Casual owners may not be aware of the requirement, especilly since the failures don't show up right away. There are horror stories about cars that have been sitting parked for years, only to find your symptoms when restarted years later. On opening, the metal around the coolant passages is so corroded by the aged coolant that there isn't enough left to hold a gasket.

-----

With coolant in the oil, DO NOT try and start the engine again. Coolant is a poor lubricant on its own, and mixed with oil will quickly cause bearing and bore damage in the engine. Drain the oil and the cooling system now to at least stop the chemical damage.

You may decide to pull a head with the engine in place, but it really is easier to pull the engine to do this. You'll have a chance to evaluate the condition of the block and heads, plus the crank main and rod bearings that have been washed with coolant and run now hot without oil lubrication.

There are often 16v engines available used from various places. 928 International has them ready to ship. Traditionally, they offer a 50%-off sale between Thanksgiving and New Years. I recommend that you call Tom or Mark and discuss options. It will be way less than what I see as needed to try and recover the engine you have. They sell all the parts and pieces you'll need if you decide to try and stay with the engine you have.

Regardless of which of those ways you go, get the old engine out and pull the heads to see what's been damaged. If everything is magically OK, you'll need a gasket set to put it all back together and should buy a lottery ticket.

Good luck with your project!

Ahh coolant in the oil,

Disconnect the battery

As Dr Bob said, dont run the engine anymore,
or crank it for a compression test,
drain the oil and coolant,

forget about a water pump for now and remove the engine from the car.

Am afraid to ask how much you spent on this so far. (Hopefully much less than when I brought home an 84 basket case of my own 6 years ago)

But I can tell you that solid running, very presentable mid year car would set you back about $4200. Less if you really hunt. Then it will still require about $2000 of refresh, they all do at that price point.

Here, you are looking at a major engine repair or replacement. Not sure the tranny condition, but the interior is a bit of a mess and its a repaint.

Major league enthusiasts are posting to your thread and will help lead you through.

But based on your comments about not having indoor space to work and key tools, make strong consideration of punting.

I bought it for $1000 without a title. I'm halfway through the process of having a title granted to me by the state, so maybe that could help. How much would it be worth? My dream is to own a 5spd version...

If it ain't broke, I'll fix it 'til it is

Also, this car WAS solid running except for the transmission leak.. It makes me so sick to my stomach because I'm the one that did this...

If it ain't broke, I'll fix it 'til it is

The damage isn't to bad. I do understand a 1000 is a lot for a college student.
You will get a 5 spd.
I don't think it will be this one.

If only want to get it back to running right for now then only replace the blown head gasket and leave everything else alone. Deal with the intake refresh and everything else when you have more money. With lots of elbow grease and couple hunded $$$ you can get it back to running again.

What I really want to do it get it running and reliably drivable for now, and slowly refresh things in the drivetrain and interior as money is available, and in 6 years when I get my M.D. I'll drop it off at porsche and have it made perfect. That's how it would work in my perfect world.

If it ain't broke, I'll fix it 'til it is

Lazer,
A little off topic, but in 6 years when you get your MD you'll have at least a Residency ahead of you and will have little time and little money. My graduation year was 1990.

And after residency I plan on fellowship. I'm trying to become a cardio-thoracic surgeon. So in all I have 18 years of school left, but I'll be able to afford fixing my car sooner than that hopefully.

If it ain't broke, I'll fix it 'til it is

Hi Lazer,
I've been a surgeon for 35 years. I still fix my 928 because nobody else near me would do a good job. Also, CVT surgery is a dying trade. I would look elsewhere within medicine for developing fields.
Best of luck to you and PM me if I can be of any help.
Dave

Specialize in breast implants and you'll be rich in no time. :)

Breast implant surgery is very competitive. You will not be 'rich" unless you are one of the best in the field. Most of medicine is highly regulated for the benefit of our paternalistic government. I did not advise either of my children to go into medicine. It has become a nightmare.
Sorry, I am even more sorry that nobody good will be there to take care of me when I need it,
Dave

I meant my comment with a good dose of sarchasm. :)

I did the same. My daughter is a high school senior and she wants to be a doc. It is a noble profession but living and working in it has become... well let's say disenchanting and complicated.

Hi Imo,
I understood. The general public might not see the flaw, however. That is why I clarified.
Dave

This, and more importantly it is my pastime and diversion.

So I'm OK calling the 928 some kind of masochistic 'therapy'? That's my story, yer 'onner.

No dr bob, not masochistic. Kind of an affirming of one's ability to make it right regardless of the challenges faced kinda thing.

..

yep.

Is there any way to test for a cracked block? I'm buying my tools for all the tests you told me to do tomorrow and if there's anything I can use to test for that I'd like to know before I get the tools. Or is that even a possibility? After checking the oil cold it returned to normal viscosity and level so I think I was just being a dumb ass and getting to excited when I said there was water in the oil (sorry bout that). But the missing coolant is still very real, and while id assume its the head gasket I don't want to mark cracked block off the list just yet. I have more free time over the next few days so I'll be able to run all the tests and let you all know what I find.

If it ain't broke, I'll fix it 'til it is

Water in the oil looks a lot like a waek chocolate milkshake, and and oil smape drawn from the drain starts out as coonat and changes to oil after the coolant drains. IOW, the oil floats on the water/coolant when allowed to settle. If you are looking only at the dipstick, it will look like all oil since it only goes a couple inches deep.

Drain the oil sump and decide if there's coolant under the oil. Put fresh oil in (doesn't need to be anything special), pull the ignition and fuel pump relays, and the plugs, and do the compression test with no coolant added. A cheap parts-store gauge is fine at this point. Some chain stores will rent you one for free with a deposit. Make sure the battery is charged. The compression test will tell you if there's a gasket, head, valve or block failure. If you have a weak hole or two, you know the engine needs to come out. You'll be able to see the failure once the heads are off. Don't spend on a leakdown tester at this point, focus on the compression numbers and report back.

Alright, I'll do that. Over the next few days I plan on cleaning all of the electrical grounds, replacing all the fuses, draining/replacing the oil, doing the compression test, and going through some of the other tests other users mentioned. How can I tell the difference between gasket, head, valve, or block failure with a compression test?

Please follow to the letter what I posted in post 32,
after you do that please post the results of what you found .

NOTE you keep asking for answers and provide no information on what has already been suggested to do,
if you wont follow these directions it will become a cat chasing its tail repair procedure,
and nothing will be diagnosed and or fixed properly

from post 32

you would be wise to remove the plugs take a picture and post it,
then do a compression test,
then remove the aircleaner and inspect the intake for oil puddles,
you may be sucking oil into the intake and not have a HG issue.
but rather a water pump /thermostat issue.

It would also be a good idea to get another 928 mechanic to look at your car,
as misdiagnosis will only cause you to fix something that may not be broken,
we can only do so much on guessing ,
the more info you provide adds to the diagnosis being closer to correct for your situation

Beyond what MrMerlin recommends, I'd start off with replacing the oil, pulling the plugs (with pics to the group), and the compression test. It won't tell you which possible path is leaking, but will confirm that you have a leak or leaks that require the engine to be disassembled for inspection/repair/replace. If no leaks then we go a different direction.

I previously suggested a leakdown test, but that's only after a compression test indentifies that you have a leak. It also requires a potentially expensive tool, and also requires compressed air. It's handy info but not really applicable if you don't have good compression. You'll have the engine out and the heads off, and will be able to easily ID the failures. So no need for leakdown testing at this point.

Cleaning grounds is a fun task, but not critical to the problems at hand. If the engine fails compression test, decide a path forward or back before you invest any more time or money in the car.


My recommendation anyway. So plugs out, with pictures. Then compression test, with results.

Spark plugs are pulled, compression results coming in a second.

Attachment 758586



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Those are starting from passenger side, back of motor, moving forward then front of motor on driver side. I also found this in the air intake

Attachment 758594



Attachment 758595

I'll post compressions in a few minutes, until then, what do these pictures say to you?

If it ain't broke, I'll fix it 'til it is

Just found this on the threads of my compression tester after testing one of the cylinders.. Not as optimistic anymore

Attachment 758596



If it ain't broke, I'll fix it 'til it is

Drivers side compressions


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Passenger side compressions



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Attachment 758610



If it ain't broke, I'll fix it 'til it is

the plug that has a bronze coating has coolant in the cylinder. picture 5,
NOTE the first two pictures dont show the tip in the sun that makes it hard to read.

the compressions are low should be about 145 to 170
BUT they are all close so if the gauge is leaking a bit then the numbers will all be low,

mrmerlin, I uploaded the passenger side compressions, and they are all 145-155 range. also, the two middle cylinders on the drivers side were both spraying coolant out when I was turning the engine over, so I suppose that's pretty definitive; Drivers side blown, passenger side fine.

Plugs 5 to 8 definitely look washed. The low compression numbers are consistent. Too bad, let's hope it is just the head gasket.

OK well you know where the coolant is.

So spray about a 30 second spray into both of the coolant filled cylinders and turn the engine over slowly by hand,
this to displace the coolant so the rings dont rust.


you will need to pull both heads as replacing only one HG is a sure fire failure waiting to happen

Was the throttle blade open during the compression testing? Also, are you sure it was coolant and not fuel vapour coming out of those two cylinders.

looking at the plug tips 6 and 7 you can clearly see they are rusting,
this means water is in the cylinder

I'm friends with a guy who went to UTI (or something like that, a mechanic school) and John henessy school of performance, and his dad is also a mechanic, and I think they'll do the job for $1000 If I buy the parts, so my plan if action is to buy the GCS head gaskets from 928 motor sports, and have them do the job. They aren't porsche experts, but I've seen their work and I trust them, and it's all I can afford as well. I'm also going to pickup the heads once they get them off and take them to a local machine shop to be re-worked, and also have the high compression lines from the transmission rebuilt while the engine is out. My goal is to get the car back to the condition it was in when I purchased it, and refresh what I can from there. I think I'll beable to get it on the road again for about $2000? Then I'm going to save up to drop it off at porsche for a full refresh. Once I get my phlebotomist certification I should be able to do a lot more refresh work, but for now I just want to get it on the road again. Am I just dreaming? Or is that a good path of action?

If it ain't broke, I'll fix it 'til it is

Buy a Victor Reinz engine gasket HEAD set, Roger should have it
also get a silicone pan gasket and a new Laso waterpump.

link to full gasket set,

http://www.ebay.com/itm/VICTOR-REINZ...ddb24a&vxp=mtr
[url]
here are some E bay links for the parts you need.
NOTE it would be better to buy the head set as it will cost less than piece buying all of the gaskets.
not shown are the 8 exhaust gaskets or the valve stem seals or the rear cam tower gaskets get the silicone versions
and install new motor mounts as well Roger has the Volvo mounts

http://www.ebay.com/itm/Porsche-928-...435b35&vxp=mtr

http://www.ebay.com/itm/Porsche-928-...04f0f3&vxp=mtr

http://www.ebay.com/itm/Porsche-944-...32b252&vxp=mtr

http://www.ebay.com/itm/Porsche-924S...4b31ca&vxp=mtr


http://www.ebay.com/itm/Porsche-924-...24875f&vxp=mtr

Before buying ANYTHING pull the heads and see what shape the mating surfaces are in. Usually a rotten head gasket comes with pitted heads/block. If the heads are pitted, are they shallow enough that a skimming can remove it?

MRMerlin, does that gasket set also have all of the other gaskets you linked to, or are the ones you linked to the ones I'll need to buy if I don't buy the full set?

the first link should have all the gaskets,
it wont have some of the O rings like for the oil pump and a few other things,

NOTE that after you figure out what needs to be fixed then you order the parts

LazerSquid--

I didn't pick up where you and the car are located. Post that in your header, and add your signature line with year and stuff. From location some may recommend a local 928-savvy mechanic who can help you when it gets to that point. You mention taking it to Porsche, which is generally NOT recommended. All the dealer mechanics who went through 928 training have retired or moved on, so you get the lowest guy on the lowest totem pole doing the work. Dealer repair quotes end being crazy catch-all numbers that are intended to cover their butts through all contingencies, and scare you off at the same time.

You can buy a great CD set of the workshop manuals through Roger at 928srus, one of our sponsors. Good used, rebuilt and new parts come from Mark and Tom at 928 International, and new from Roger. I wouldn't think of diving into the car project without the manuals.

You should invest in a Rennlist membership too. For a very few dollars, you get all this support with no pop-up ads. Build a profile with all your info in it so we don't have to search for what car you are working on or where you live. Membership here and at the Owners' Club gets you perhaps the best return on investment you'll ever see with a 928 (short of driving it...).

Alright, I just wanted to post another update on what's going on. I remembered one of the guys at our local car club is an incredible mechanic, and I'm pretty good friends with him, and I'm currently negotiating a deal to trade one of my spare engines that he always wanted (a FI 13b rotary) for the labor to have the gaskets and rings replaced, new waterpump and timing belts, and while it's out I'm going to replace the motor mounts and have the high-preasure hoses from the transmission rebuilt, along with re-decking the heads. I'll be paying for the parts, which I figure will come out to about $1k, and he'll do the labor at his shop. Does anybody have any objections to this?

Dr. bob, I already have the workshop manuals for the car, and I already bought the rennlist membership. Also, I'm located in northwest arkansas (XNA area), home of walmart, and the car is an automatic 1984 928s that I acquired from a local redneck (who trashed the poor thing). I'll update my profile with all of that info tonight.

depending on the block condition rings may not be necessary
NOTE you just dont toss a new set of rings into the block because its open ,
Though It would be a good idea to pull the leaking cylinders pistons out to inspect the rings, if they are stuck or corroded then yes new rings,
NOTE the pistons are specially sized for this block so they must be saved.
NOTE to clean them only use a tooth brush and soaking in simple green,
the dull green coating is chromium and this is so the pistons dont seize in the alusil block

Oh. I was told that when aluminum blocks over heat, they usually squeeze down on the pistons and warp the rings, if that's not true then I won't replace them

well you should inspect the rings on the two cylinders that were leaking coolant.
And one of the middle cylinders from the other bank then this will also include checking the rod bearings 2 and 6 are the rods that wear the most
If you do install new rings they have to be sized IE the end gaps checked,
and then you dont do anything to the block except to clean the cylinder walls with acetone then add some oil prior to installing the pistons

Well I guess the reason I worry about the rings, is because the whole row of cylinders was low on the drivers side. Passenger side all read 145-155, but drivers side were all 100-130, even though only the two in the middle had coolant in them. Could the outer cylinders have low compression just because of the head gasket being blown out in the middle? Sorry if these are dumb questions but I'm used to individual head gaskets (motorcycles) that don't cover more than 1 cylinder each.

I suppose it would be much cheaper to go ahead and buy the leak down tool and test for it that way. I'll look into buying one tonight after work.

On second though since you did have a few oveheating episodes,
I wouldnt buy the leakdown tool just replace the rings and refresh the heads

Don't bother with the leakdown tool, since you'll have it all apart anyway.

Rings "fail" by wearing, by losing spring tension, by breaking. They get stuck in collapsed ring lands in the pistons. Any or all of these will be obvious when you pop the pistons out of the holes. Be sure to mark which bore they came from and which direction they were each facing, and reassemble in the same place and position. You'll test the old rings for tension, inspect them and the bores for coincident wear patterns, know their fit in the pistons before you disassemble them, etc.

The pistons have a special coating that must be maintained, so heed the MrMerlin warning about nothing more aggressive than Simple Green and a toothbrush. The block prep is similarly sensitive. So despite the temptation to just clean things up a bit, you must limit that cleaning to detergent, toothbrush or similar soft material. No Scotch-Brite, no steel wool, no sandpaper, no de-glazing, honing, sandpaper or ridge reamer on any of the bores. Be sure to alert your engine builder to these concerns.

----

A few years ago, a guy in the Philly area decided he could make money breaking and recycling parts from 928's. In the process, he saw that good matched piston sets at other vendors could selll for more than engines, so he took the engines apart and wire-brushed all the pistons to look like new aluminum. In the process he removed the skirt coatings and trashed the ring lands. Made scrap out of what might otherwise have been usable parts.