bleachii

My '79 930 (owned since '98) has a number of oil leaks and really needs a valve adjustment as well. The oil leaks have been there for a couple of years now and at least one is really bad (pretty sure its a oil return tube). I don't drive the car very much so the valve adjustment is due to time rather than mileage. Also, since I plan to have both lower valve covers off it seems to make sense. I know this is an expensive repair at the shop so I've decided if I'm going to keep this car I really need to learn how to do some of these repairs myself. Unfortunately I'm good at working on computers but my mechanical skills are non existant. I've booked 3 nights at a Holiday Inn Express for good measure

I've 'almost' started this project multiple times now but end up getting nervous and never starting. The whole thing scares the bejeebers out of me. Finally this weekend I have begun. I'm going to try and document it here for others in a similar position. I'm a computer nerd by trade so my mechanical skills are oil changes (not on a Porsche) and I once kind of helped a guy pull the engine out of his 911 so I could learn something about my car. Here's a couple of notes about my experience level.

1. Do not own a 17 mm box/open wrench
2. Had to google box/open wrench to be sure I was talking about what I thought I was talking about
3. Have never changed the oil in my 930 myself
4. Didn't visibly know the difference between a heat exchanger and thermal reactor

This is going to be fun

Yesterday I took the car for what I hoped wasn't its final trip around town to get the oil heated up. Jacked the car up using the controversial 'sump' method and prepared to drain the oil. Devil is in the details

I used one of those 15 quart oil pans with the really small reservoir on the top. Picture included. Removed the oil plug and wow does that oil come screaming out! I had another 7 quart open pan just in case the oil couldn't drain into the pan fast enough. Everything seemed to be ok but the damn oil kept coming, and coming, and coming. Then, very quickly the oil filled and over flowed as I swapped to the 7 quart open model. You can't possibly swap between the two fast enough. Had to be a half quart or more on my floor. I laughed! First step in and I'm already looking like the rookie I am. One thing about oil too, it gets on everything! Oil is not easy to cleanup!

Anyhow, 20ish minutes later I returned to remove the sump plug for the rest of the oil scared to death it was going to leap from the hole, run down my arm and onto my face. Ended up with no issues and all oil out of the car. Also sprayed some of the nuts/bolts holding the heat exchangers to the thermal reactors with WD40.

I did take a few minutes to scope out the upper and lower valve covers as well. Was pretty sure there wasn't an upper valve cover on the driver side until I spotted a small corner of it buried under an intercooler and bunch of stuff I don't know the names of.

Enough fun for one day I decided to call it a day.

Today I decided to tackle the filter with my filter removal tool. Nope. Big Filter. Little removal tool. Filter very tight. Will come back to it. The filter wasn't even on my list of 'stuff that will be hard'.

Today was more WD40 to the nuts on the heat exchangers and I decided to tackle a few of the easier to access nuts just to see how difficult they might be. Once I figured out I needed a 17mm open ended/box wrench is also about the time when I figured out I don't have one

I did have a couple of 1/4 drive 17mm sockets and was able to loosen about 3 of them. Enough to realize just how difficult they are to loosen. And these were the ones where I had good leverage. A few of them look very difficult to access and I'm choosing to ignore the thermal reactor for now which doesn't even look possible. I did spray the thermal reactor nuts with wd40 but I don't even want to think about that challenge yet. I'm familiar with the broken stud horror stories. I'm tackling this one step at a time and right now that's one nut at a time until I get the heat exchanger removed.

So, all cleaned up and not sure if I will have time during the week....or light for that matter. Might not be able to work again until next weekend. In the mean time I'm going to be reading and I'm heading to the store to get a bunch of stuff I don't have including the following items. If I'm missing anything let me know.

Lighting
Oxygen Mapp Gas Torch
Propane Torch
PB Blaster
Sil Glyde (for the Oil return tubes)
Snap Ring Plier Set (per pelican tech article)
Torque Wrench
.0025 and .003 feelers (back side method)
Beer
Marijuana

I'll post more as I continue to make progress and/or mistakes.

Take Care,
Brian

A930Rocket

Sounds like you're getting there. Do you have any manuals to help you?

If you haven't poured the new oil yet, DO IT NOW. Don't wait until you change the filter, as you don't want to start the car by accident, with no oil.

Why are you working on the heat exchanger nuts? If you're not swapping out headers, then I would leave them alone. They are prone to breaking off and that would not be fun if you just looking to see what's in there.

bleachii

I'm a long way from getting to start my car again. 3 of 4 oil return tubes are leaking so I plan on replacing all 4. The driver side lower valve cover is leaking as well so figured I might as well change both valve cover gaskets. Access to the valve covers and oil return tubes is very difficult if not impossible without removing the heat exchangers. I'm not yet sure if I will need to remove the thermal reactors for access. The thermal reactors are bolted to the engine while the heat exchangers are bolted to the thermal reactors. I got some PB Blaster tonight to help with the process.

Since the covers will be off and I'm past due for a valve adjustment it seems to make sense to do that as well. I have the 101 projects book and the performance guide. Other than that I'm reading every thread and article I can find on tips and methods people have used to do these projects. It's not rocket science but I don't have that arsenal of tips and tricks at my disposal. And there's plenty of stuff where I just look at it and think 'what the hell is that' or 'how the hell am I going to get that removed'

These projects are all things that are either notorious for failure (return tubes) or require regular maintenance so it seems to make sense for me to use them to learn more about my car. I would rather not do the valve adjustment but if I pay for that I might as well pay for the rest of the work. I'm in no hurry. I'd like to be finished by Spring.

I appreciate the tip in regards to filling up the oil NOW. I am keeping a checklist of stuff I have to do and check off before I will attempt to start the car again. It's on the drivers seat. I haven't even completely tightened the oil and sump plugs yet as I read they should be torqued and I don't have a torque wrench yet.

Thanks for checking in.

bleachii

Borrowed a neighbors larger filter removal tool and replaced the filter this evening. It was on tight and required quite a bit of strength to loosen. Too tight for me to do by hand.

Also managed to loosen 6 out of the 14 nuts holding on the heat exchangers after spraying some PB Blaster earlier today. Some are accessible but very tight while others are not easily accessible and appear to also be very tight. If I can't get a box wrench around a nut in a tight space is the next best bet a open wrench? It feels like too much brawn with the open wrench might slip since it doesn't have as much grip as the box end. Really don't want to strip any of them. Is heat the next step maybe?

Thanks in advance for any help.

Brian

bleachii

Courtesy Pics.

3rd pic shows up close the Heat Exchanger Connection to the Thermal Reactor. Last pic is same connector with perspective.

johnlush

Brian, Congratulations for deciding to tackle this yourself; you'll learn a lot about your car by working on it. I agree completely with Rocket about questioning messing with the exhaust. Be especially cautious if you choose to remove the thermal reactors from the heads. The potential for breaking a stud is huge and the consequences aren't real fun. Also keep a running list of parts that you will need for reassembly - gaskets, etc. On the top side you will want to remove the intercooler (be sure to seal off the openings with a rag, tape etc. to keep crap from falling in) and the A/C compressor. Don't remove the A/C lines, just unbolt it from the mount and swing it out onto the fender. Use a very large towel doubled over a few times to protect the fender. You'll find a wealth of information here and over on the Pelican BBS to help.

BTW, your car is beautiful! Minerva blue has to be one of the best colors for a 930 and I've looked long and hard for one! What color is the interior?

Regards,

John

bleachii

Thanks John. I'm hesitant about attempting to remove the thermal reactors and will avoid removing them if at all possible. After further exploration last night it looks like I might be able to work around them. If I do however I need to remove that 'thing' to the left of the thermal reactor in the last picture above. The 2 passenger side oil return tubes are above the 'thing' and the thermal reactor. I just don't have acces without one of them being removed. Driver side looks relatively clear.

I don't have much of a choice regarding the heat exchangers as they are covering the valve covers.

Thanks for the tips re covering the openings, towel, list of parts, etc. That's exactly the kind of reply's I'm hoping to get. Hoping to find out I'm doing something stupid before I do it and learn as few 'lessons' as possible.

MUSSBERGER

Geez your car doesn't look that bad underneath. I was doing a valve adjust on my SC one time. I broke one of the special feeler gauge blades and it fell where I couldn't see it.Talk about panic. I fished it out with a magnet and put the covers back on. I pay to have it done now

bleachii

Muss....I think the pics are just not showing the oil and grime.....it's there.

So last night I went to Sears and Harbor Freight to find a better tool for removing a few of those difficult to reach nuts where the heat exchanger connects to the thermal reactor. The 2 top nuts on each side were giving me fits. A sign of the times the stores (particularly Sears) have so few clerks it's very difficult to get help. Anyhow, I left with just a pair of overalls and a long handle 17mm wrench.

When I got back to the car I realized I could get to the bolts rather than the nuts with a socket and an extension. So, the problem was mostly that I was tackling the problem from the wrong side. They were still very difficult to remove but I managed to get them all loose.

So as of last night all of the 14 nuts are loose and I was able to remove the right side heat exchanger exposing the valve cover. I can see that it is leaking as well so that means I have both lower valve covers leaking and at least 3 of 4 oil return tubes. Will remove the left heat exchanger tonight hopefully.

Couple of questions if anyone can help. Any recommendations on a cleaner to start cleaning these parts? Lots of grime on the heat exchangers. Also, looking at the photo of the thermal reactor there is a smaller 'tube' looking thing right next to it. Anyone know what that is? Anything I need to know before I remove it? I can't get to the right side oil return tubes without either it or the reactor being removed. It looks to be the easier component to remove especially based on comments above regarding the studs.

Including some pics from last night's work.

bleachii

John, forgot to answer your question earlier about the interior. The color is cork.

BTW....I'm finding this project to be very much in line with troubleshooting computer networks. Obviously the problems are very different but the logical thinking process is the same. I'm finding it almost therapeutic while I am out there working as I completely forget about work stuff while I focus on a 'nut'. I'm sure a real mechanic would laugh at how long this is taking me!

TOMDEG

Beautiful car.
The smaller "tube " thing is the EGR filter.

Tom

bleachii

Thanks Tom. Any issue with removal like something spilling out of it or vacuum issues or anything? Or is it just straight removal and put it back on. I googled egr filter and searched on pelican but no results. I can see it pictured in the turbo exhaust parts diagram on Pelican but it's just a picture.

Megatron-UK

The condition of the heat exchangers and all the nuts looks pretty good - probably made it a lot easier than the job I had when fitting a new exhaust system last year:



....eurgh!

bleachii

Alright. Did some more homework. Finding information is not proving to be very easy as I am having to piece it together from reply's, other threads, various books, etc.

Based on now understanding that EGR stands for Exhaust Gas Recirculation I'm guessing no issues with vacuum/fluids per my question above. I'm not yet certain but it sounds like EGR, EGR Valve, EGR Filter are all pretty much synonymous.

Per a google search (about.com) I learned this about what the EGR does: emission control device that sits between the exhaust and intake manifolds on a vehicle engine and regulates the amount of spent exhaust gas that is mixed into the intake stream. Its purpose is to cool combustion chamber temperatures to the threshold that reduces the formation of nitrogen oxides (NOx). The higher the combustion temps, the higher the formation of NOx.

I pulled out my 101 Projects book and 911 Performance handbook and while I can't find anything in the 101 book I found the following in the perf handbook.

p. 72 states: Focus of 1975: California Emissions...."first year of the abominable thermal reactors and EGR (Exhaust Gas Recirculation) for California cars."

Sounds like in later years this setup made it's way to other US Porsche models as well (personal hypothesis) and not just CA cars since I dont' believe my car was specifically a CA car. It came into the USA via the Pacific Northwest and was delivered to a collector in Seattle area. I purchased it from him in '98 and have the original window sticker and dealer delivery info. It was one of the last cars delivered in Dec of 1979. I don't have the info in front of me but I believe it came in via Canada (Vancouver I believe).

Wow Mega! Now I understand how fortunate I am and what everyone is talking about with the rusty nuts. My car does look good compared to that.

jwasbury

Good on you for taking on this job yourself.

As you have already learned in your research, heat is your friend in removing the stuck fasteners. If you are going to remove those thermal reactors (pretty rare to see those in the car still, except in California I suppose), I suggest you have an arsenal of wrenches for the task. Nuts will typically be 13mm or 12mm. I use a regular combo wrench, a stubby flex-ratcheting wrench, a "deep offset" box end wrench, and a 1/4" drive swivel socket to get all those nuts off since they can be difficult to access.

I'm suprised that you say you need to remove the heat-exchangers to access lower valve covers. That shouldn't be the case. I had the same exchangers on my '79 (also Minerva Blue) and was able to remove the valve covers and perform a valve adjustment with the exchangers in place.

Oil return tubes may be a different story. The PO of my car had replaced the oil return tubes and I believe he left the entire exhaust system in place. My car did not have the thermal reactors anymore, however as they had been replaced by "thermal reactor delete headers"

Good luck and enjoy