Questions Regarding "Fixing Common Oil Leaks" Project

[Dooodahman]

Hey everyone,

With the help of many threads on these boards, I recently dropped my engine for the first time (see obligatory pic below). I am now tackling the common oil leak areas. This is the first engine work I've ever done, so I have no experience to fall back on! As a result, I have a lot of probably very basic questions. Hopefully, someone here can help.

So far, they are:

1. Intake Manifold - I removed the intake manifold to get to the breather cover. (Spent all night thinking I had dropped a washer in the intake, but found it this morning in the AC mount!) I will be replacing the 12 gaskets, since the ones on there now are flaking, but is it a good idea to always replace the inner flanges as well?

2. Gaskets - Do you typically replace the breather cover gasket dry, with oil or with a sealer? I have the same question for the 12 intake gaskets.

3. Washers - Obviously almost every fastener has a washer, and I assume they should all be replaced with new. How do I go about replacing these with proper replacements? Are these just normal aluminum washers or do I need to find the right part numbers? Also, do the thick intake manifold washers also need to be replaced?

4. Thermostat - I replaced the o ring on the thermostat (liberally coated with oil) and then realized I did not remember which way it went back in. From the placement of the openings, it appears there is a right way and a wrong way, but when I took a picture before I started, the cover was so covered with sludge that I can't tell which way it was in. I think I have it lined up so the higher opening in the thermo matches the higher hole in the housing (which I think is the side nearest to the fan) - but is there any way to know for sure which way it is supposed to go back in?

5. Distributor Cap Wires - I saw some articles mentioning dialectic grease, others not. Is there a consensus on this?

6. Mystery Breather Cover Sensor - there is a sensor in the breather cover, adjacent to where the breather hose connects. (Not the red Oil Pressure Switch, which I have replaced.) It looks like a temperature sensor of some kind, with a solid probe that extends into the breather cover. Anyway, I'm not sure if it is leaking or not, but since I am in the area, what is this thing and is there anything to do here as far as oil leak maintenance?

7. Oil Pressure Switch - All the directions said to replace with new crush washer. The one I bought here came with a teeny tiny one already attached. I assume this is all I needed?

8. Transmission - The shaft coming out of the nose of the transmission is surrounded by a collar with a smooth surface that faces the front of the car. The surface appears to be peeling. Is this just a residue that needs to be cleaned off or is something actually peeling? If it is peeling, is this a wear item I should address now? I have no idea what this thing is, never mind how important it is or how to fix it if need be! And I really don't want to take apart the tranny.



As always, your help is much appreciated.

Thanks,

Andrew

[Ngrich99]

Not gonna answer your questions but sweet pic with the kid and the porsche. Memories for sure. That is why I like mine most, car, Kids and lasting trials and tribulations as we work and drive together.

[afterburn 549]

Brake clean the idiot switch and put a coating of your flavorit favor of epoxy on to where metal meets ceramic.
The crimp always leaks at some point.

[Techno Duck]

I just did similar work, albeit with the engine still in the car.

1. I would replace the spacers also while its apart, general consensus is that they warp with age and will induce vacuum leaks. Mine were cracked and falling apart so it was a no brainer.

2. This is personal preference. Clean all gasket material and install dry is probably the general method. But on certain paper gaskets i use a sealant called hylomar. This is non hardening sealant, it makes removal of the parts in the future if needed much easier. Everyone has a different method for the intake gaskets; Curil-T, copper spray sealant..etc. I chose to install mine dry.

3. I would not worry about replacing most of the washers unless they are split / locking washers. Generic zinc coated hardware can be used that you can get at a hardware store.

5. Use grease on the rubber boots, this will aid in removal of the wires from the cap and plugs in the future.

6. The sensor in the breather turns on the blower motor in the engine compartment to aid in cooling once the engine is shut off. Sealed with a crush washer which is easy to replace, but probably not the source of any leakage.

Some other suggestions while the engine is out; replace the three fuel lines on the engine that are prone to leakage. This is the T shaped line under the intake, the straight jumper line that connects the passenger rail to the regulator and the J-shaped hose that connects the regulator to the return line.

Its also a very good time to replace all the vacuum hoses on the venturi tube behind the intake manifold. All of mine were loose, the hoses had shrunk with age and the crimped Oetiker clamps were no longer tight. Its also a good time to replace the main hose for the brake booster which is often cracked where it runs under the car. This hose connects to the venturi tube on the back of the intake, then down to the center tunnel to a tube that runs up to the brake booster up forward. I replaced this hose with the engine in, intake still off. It was a MAJOR pain in the butt to do. It will be much easier with the engine out. The short sections of hoses on the venturi are the same size as the brake booster hose, 19mm.

Brake booster hose - 34-33-1-115-926-M20 . Get atleast 6 feet if you want to replace the entire section, you should have enough left over to do the venturi on the intake also, you only need a few inches for that.

[fanaudical]

#2 - I like a thin coating of Curil-T on my flat paper-like gaskets. Others will disagree. (My 2.7 doesn't leak.)

#3 - I recommend replacement with aluminum sealing washers if that is what is originally equipped.

#4 - Although the thermostat appears symmetrical, it's not. It will only fit over the studs one way.

#5 - I like dielectric grease on boots; it makes servicing easier later without ripping up the boot.

I'll second the sentiment about replacing vacuum lines and anything else rubber that's not difficult to reach while the engine is out. Also not a bad time to check the blower motor, starter, etc.

[Dooodahman]

To everyone that has weighed in, a huge thanks. These were exactly the answers I was looking for. I have already changed the fuel lines (thanks, Len) and have the breather hoses on my to do list, since they are cracked. I will check over the other lines/hoses as suggested.

One thing I will NOT be doing is the clutch. People here keep telling me to do it while the engine is out, but I priced it last night....YIKES!!! I'll keep it as is for now and see how it goes! My main concern was the safety issue of doing the fuel lines, fixing the oil leaks are a nice bonus. The clutch can wait!

One new question: Len's lines obviously do not fit in the old hard line's mounting points, and I am concerned about the bare rubber wearing from vibration. Is this a realistic concern? On the passenger side "T" part I put on one of those plastic spiral protector things that was on line I replaced on that side, but there is none on the drivers side or main line that runs down the middle. How have you all routed and secured replacement fuel lines? And what, if any, protection have you put on there to protect form rubbing?

Again, many thanks everyone. I'll keep you posted.

Andrew

[kent olsen]

Regarding the clutch. I've had my 2.7L and 3.0L out of my car for various reasons over the last 15+ years and always replaced the rotating disc. The pressure plate will be ok for a long time if the disc doesn't get worn so much that it generates a lot of heat onto the pressure plate. Between my 2 engines my pressure plate has been in there for near 150,000 miles and I do a lot of track and autoxing.

[Dooodahman]

Originally Posted by kent olsen

Regarding the clutch. I've had my 2.7L and 3.0L out of my car for various reasons over the last 15+ years and always replaced the rotating disc.

Kent, do you mean "Kit PEL-G50SK-1N: Clutch Disc 240 mm (Spring Hub)"? If so, are there any seals you typically replace at the same time?

Thanks,

Andrew

[kent olsen]

looked up our hosts parts for 88 carrera. Ouch, more than mine but, clutch disc #930-116-014-02 M38. Also replace pilot bearing, #931-102-111-02 M34. Goes in center of flywheel, transmission shaft noses into it at the flywheel.

[steely]

Not what you asked for, but consider re-bushing the throttle linkage bell crank on the side of the trans (and top of engine deck), and inspect your speed and ref sensor lines for signs of crumbling insulation. If bad, it is time - the BMW parts are a safe and less costly solution. Definitely Yes to vac line replacement too. we will spend your money.

If you do your clutch, I forget what G50 years were involved, but there was some sort of modification made to the throw-out bearing fork - mentioned in Waynes 101 Project book.

Great pic and avatar!

[Dooodahman]

Well, it's time to mount up the engine and I have another problem...



Bit of a gap, eh? Guess I shouldn't have gotten the 2000 lbs. engine stand.

Any ideas how to fill it?

Andrew

[ischmitz]

I'd get a cheap one rather than "filling' this. You'd need a custom-fabbed pipe of sorts and having that made up is probably more than getting another stand.

anything else would be improper and if the engine drops you won't stop kicking yourself....

[Dooodahman]

Originally Posted by steely

If you do your clutch, I forget what G50 years were involved, but there was some sort of modification made to the throw-out bearing fork - mentioned in Waynes 101 Project book.

Great pic and avatar!

Thanks for the tip on the fork. I recently discovered that a PO had the upgrade done to the bell housing ears but I am a little stumped by the fork in there now, as it has metal and not plastic bushings. See Update G50 Clutch Fork

Anyway, is your username in reference to the wheels or are you a friend of Jerry's as well?

[Dooodahman]

Originally Posted by ischmitz

I'd get a cheap one rather than "filling' this. You'd need a custom-fabbed pipe of sorts and having that made up is probably more than getting another stand.

anything else would be improper and if the engine drops you won't stop kicking yourself....

Well....lesson learned: Stick with the 1000 lb. HF engine stand.

Maybe I can return this one and bring the P201 with me to HF to make sure it fits. Dropping the engine (in the literal sense) is not allowed!

Turns out I also need to grind out a bit of the P201 to clear the heat exchange joint like some others have mentioned on here:

[Dooodahman]

Well, I sure am glad I finally got around to dropping the engine so I could swap in Len's fuel lines.....

[steely]

wow - you said it.

[jlex]

I dunno.... looks like you may have had 2 more plys left on that fuel line...

[Dooodahman]

Cracked open the valve covers today and did my first valve adjustment. Went relatively smoothly, but even with all shims moved to the outside, there was still a lot of slipping of the belt (and then grabbing the belt and pulling while cranking the fan nut to get the crank to turn). Seemed to loosen up around the third revolution, but man was it stiff to start. If this is not normal, please let me know.

Also, this is what my lower valves looked like when I popped off the cover. Does this look normal? It's the first time I've ever opened them so I don't know what to look for.



I had a lot of dripping from the lower covers before I dropped the engine. About every lower nut was visibly weeping drops of oil. Now that it's open, I'm most curious about the oil around the two upper nuts in the following picture. I'm not sure how oil could have gotten up there.




If anyone knows if this is normal or a sign of an issue, please let me know.

[kent olsen]

I don't see anything obvious. Tips I've learned, turbo valve covers are a must. You may already have them on your 88. Purchase the kit that includes gasket and new nuts. That will probably solve any cover leaks. Our host probably has them. I get mine from Steve Weiner @ Rennsport Systems. Oh! if you pull a few spark plugs it makes turning the engine easier and if it is hard to turn that is a good sign.

[Dooodahman]

I have noticed that certain of my rocker shafts appear to have "walked" a bit. I want to avoid having to remove them if possible. Can I just tighten them down where they are? Or should I loosen, shift them over and then retighten? Or do I need to remove, clean and then reinstall? Pics below:






Also,one of my oil return tubes looks bent. Any need to replace or should I leave it as is? Is this something I should replace now, since the engine is out anyway, even though they are not leaking? If I should replace them (since the engine is out), any reason not to use the non-collapsable kind? I would assume the solid ones are less likely to leak, but could be a bigger pain to remove down the road.



Finally, what is this thing? It's right near the oil tank filler but I can't find it on the PET: