Techno Duck

As a part #2 to this thread...

https://rennlist.com/forums/showthre...1&page=1&pp=15

Ive determined the source of my problem, leaking headgasket on the #3 cylinder. I started the car...it was running rough so i imediatley shut it down and pulled the plugs. 1, 2 and 4 all looked perfect with the slightly white tip, #3 was wet....DOH. Peaked down into the cylinder with a flashlight and low and behold i can see the coolant dripping into the cylinder. I depressurize the coolant system and it stops. It was exactly what i thought it was, a small leak in the headgasket...I KNEW IT!!!!

On the bright side i have no mixing of oil in the coolant or vice versa. No overheating issues and nothing else to speak of. But visually seeing coolant dripping into the cylinder is disheartening to say the least!

Bah, but this sucks. I am right now debating changing it myself or just paying a shop to have it done. I think i am fairly capable of doing the job..but honestly i am just tired of working on this car and im thinking about taking it to a shop. I asked a few weeks ago the cost of a headgasket from a shop thats sort of far-ish from me and was quoted $650 +/- $75 if any machine work needs to be done. I just have this nagging feeling i am going to do something wrong and end up having to do the job over again. I would rather have a professional do it and have the warranty behind me if they do something wrong and need to do it over again .

As i debate this though, i have a question or two.

1. Do the head studs need to be changed when putting the head back on for installation?

2. I burn about 1qt of oil every 3k miles and i think most of it is burned off at high revs, i have a feeling its the piston rings which are worn. Is it much more work to change these while i have the head off?

I cant think of anything else right now.

Going to call a local shop tomorrow and see about getting a quote from them, i figure it will be roughly the same cost as they both have the same labor rate i think.

Not to bad i guess, 90k miles and the engines never been cracked open. Probably dosent help its been seeing some very heavy auto-x use.

hrsteel

#1 No, the headstuds don't need to be changed.
#2 Re-ringing a motor is a LOT more work. You will need to open the bottom end to remove the pistons and it wouldn't be a bad idea to have the bores honed while you're at it. I'd do a leakdown to determine if the rings really need to be changed rather than put new ones in for the heck of it.

J Berk

Duck

While I've never done serious wrenching on my p-car, I have on many other domestic engines....and if at all similar, you'd need to basically drop the whole motor to do rings....pan off...connecting rods off the crank and pull the pistons. Whole lot more work than a head gasket!

No idea about the studs!

best of luck


Joe

Mongo

Hey Jon, your #3 cylinder leakage is the EXACT area where mine was leaking. When you pull the head, look at the area between the #3 cylinder and the water jacket. You will find a nice shiny clean spot there indicating your coolant leak.

Techno Duck

Ok... so scratch doing the rings . I can live with 1qt every 3k miles thing...it gives the car character . Thanks for that bit of info everyone.

I just called my father for the usual good advice and here is where i stand right now with options to fix this. Alot of this depends on the quotes i get from the shops in my area, going to call up a bunch tomorrow.

1. Take it to a trusted Porsche place in my area. I have two in mind.. going to call both for cost estimates.

2. My father suggested having the mechanic at his shop do the headgasket for me. He works on his own customers cars after hours at the shop and he really does great work. This is how this headgasket job would be treated. I was his apprentice for a few months working under him, he does do great work but is more of a domestic car kinda guy. I figure going this route i can atleast offer him a hand when doing the job.

3. Do it myself in the driveway.

Option 3 i am ruling out, im just a bit tired of working on this car and really have no desire to dig this deep into my engine, the timing belt job is about as far as i want to go. I think i am going to go with option #1 first based on prices i get to change this thing. If i can get it done for under $700 i think i can stomach that. The big thing here however is finding a place that can possibly do under $700 as a flat rate for the job, id hate to think i am going to pay $650 then be smacked with a bill for over $1k due to complications or whatnot. If this is the case it looks like its going to be option #2.

I have an auto-x on the 22nd... wonder if i can get this done before then. Im always thinking ahead you know..

Andy, how many miles did you have on your motor? Did you install the FRWilk chip before or after your headgasket went? I think i am going to get the car dyno'ed after i do this headgasket and look at the AFR's running the Wilk chip. Im not saying its related, but i figure its worth checking.

Yabo

Who called headgasket!!! Good luck with it!

Yabo

oh and is that 700 with parts or striclty labor? even strictly labor i doubt it... it costs at least that usually for timing belt/roller/waterpump job.

hosrom_951

You don't need to replace the factory studs, get a tap and die kit and clean out the threads.

be sure to sand down the washers with 60 grit paper, to stop them turning while torquing the cylinder head.

replace the valve stem seals, valve guides, get a seat job etc......

MM951

Jon I'm sure your capable of doing the head gasket in a weekend or a little more...

The head comes off stupidly easy. If you've done a timing belt , removed the intake manifold (I bet you've done that since I have a picture of your engine bay saved and it has a black intake mani) your a 1/3 of the way there lol. It took me 2 hours to take it apart the first time (while labelling, cleaning parts, etc) and if you have all the parts shouldn't be much more putting back together..
'
I'd get the head pressure checked but I doubt any work other then cleaning it up and replacing the stem seals would be needed. Quick and easy check "pre-test" for guides is to stick the valve stem into the guide and try and wiggle it. If you can wiggle it more then a TINY bit ask the machine shop to check it. The only time I had to replace valve seats in the 10+ 944 heads I've rebuilt was when a valve bent and cracked the seat

anyway if you decide to do it yourself and would like a hand i'd be happy to take a trip out (sched. permitting) and give ya a hand

One thing that is a MUST in my book. While its all part replace every vac line and fitting. Zip tie the new lines on (I did away with the hard line and am using 3.2mm vac line) might save some headaches later on

Techno Duck

Mike, i already changed the vacuum lines with silicon ones, i never did ziptie them though. Thanks for your offer, i will keep it in mind.

I am still debating this. Called one of the shops in my area that is open saturdays..forgot they are not around today because its a MetroNY DE..DOH!. So it looks like this is going to need to wait until tuesday when everyone opens again.

I thought about doing this myself a little more over next weekend before i fell asleep and ill keep the option open. The two things i am not looking foward to doing are

A. dealing with stripped cam tower bolts, which seem to have been a problem for a few people removing the head

B. taking the exhaust manifold off. Ive read its possible to change without taking it off, but honestly i think it would make life easier to do so.

Another question ive got..

- What exactly needs to be done to clean the sealing surfaces of the head and the block? I am used to just taking some very fine steel wool to clean up sealing surfaces, but i think this is a situation where its going to be tough to keep the pieces of steel that stray off

Techno Duck

Mike, btw since you seem to have experience with cylinder heads. Roughly how much would i be looking at to have the head checked and the valve guides and seats replaced?

The 944Online rebuilt head looks like a nice choice to save me downtime with a direct swap, but at $500..damn thats alot! The main problem i am going to have with machine shops is that i can only work on the car over the weekends and im at school during the week. So getting the head to the machine shop is the big issue. And i would like to be able to finish this job before the 23rd so i can auto-x this damn thing.

What exactly should i order, 8x valve stem seals and 8x teflon valve seals?

500

Hey John, I think you will find the head gasket job pretty easy. However, it makes sense to have the head "done" (valve job etc.) while your're at it. I've heard good things about the 944 online re-built heads and $500 does not sound like a bad price for this.

When you get the head off, you will have a chance to look at the bores. Unless there is scoring, I doubt your rings are an issue. These blocks wear really well and blow by at this low mileage is not common. More likely would be valve guide wear (and that is something that will be taken care of with a re-done head).

MM951

I didn't have any problem with any stripped bolts. Tap the socket in with a hammer to make sure its seated squarely.. treat it like a CV joint cheesehead.. The head comes off soooo easy on these cars. People make out to be something difficult. I didn't remove the exhaust manifolds, just took the nuts off (after spraying them with some liquid wrench and letting it sit for a little while) and they slide back far enough where you can pull the head off no problem and leave everything exhaust wise together.

To pressure test a head its usually about $30, any more is really dependent on what the head needs. If nothing is damaged, its usually ~$150 total to check the head for cracks, warping, disassemble to check the guides and seat, clean up everything, deck it a lttle bit if needed, and put it back together. It goes up if theres damage.. When I'm at the shop monday I can give you the exact price list we have there

BTW: If you do need a new or want a head , I can get you a rebuilt head with your core for $250 or so. pm me for details if your interested

Techno Duck

Thanks for the info everyone. I think you all talked me into doing this on my own. Damn you all!!!

Mike, you have a PM.

Techno Duck

While on the subject of this, do i need to replace the pressure relief valve on the head or can i reuse the old one?

Can anyone give me a parts list, here is what i am looking at so far..

10x headstud nuts
10x headstud washers
Victor Reinz head gasket set. (everything needed to change the head)
8mmx12mm copper exhaust nut set