vanster

Is the replacement procedure to replace the oil pan gasket similar to changing motor mounts? I have looked for a write up but unable to find one

Wisconsin Joe

Pretty much. You have to take off the bottom crossmember to get to the pan, which means you have to take everything off that you would with the MMs.

There's a technique that doesn't involve dropping the crossmember, you just unbolt the pan, drop it the little bit to the crossmember and then "sneak" the OPG in.

I know there are people that have done it this way (MrMerlin maybe?), but having done it at the same time as the MMs, I don't think I have the skill or patience or tiny enough hands or few other things.
I can see how it could be done, but I don't think I would try it.

dr bob

Stan's method requires you to get the new OPG under the pickup, then back up to final position. Were I --only-- changing the OPG, I might try his method. Usually there are other things that need to be done in the neighborhood. You get to do a lot of the same work, like unbolt the mounts and raise the engine, and that means the starter gets dropped, slave cylinder if you have a 5-speed car. And you get to do all the same cleaning underneath so crud doesn't fall into the pan while it's lowered. You do save the fun of dropping the rack and the crossmember, and the lower front suspension pieces.

soontobered84

I just replaced my 10 year old silicon pan gasket this way on the Stepson (without removing the crossmember). The pan only drops about an inch so you aren't dealing with a large amount of space. In addition, when I originally installed the pan gasket, motor mounts, etc, I also installed a stud kit. I didn't realize at the time that some of the pan gasket bolt holes were blind. I was using red threadblocker to install the studs and wasn't careful to make each stud the same length through the pan. This did cause issues getting the old gasket past some of the longer studs, but it was mostly doable.

To reinstall the gasket or to install a new gasket, I used an engine lift, not unlike those used to support the engine during a crossmember-out pan gasket replacement. This allowed me to raise the engine another 1/2" or so without unbolting the MM's. Amazing what an additional 1/2" will do for your psyche (in more ways than one) It was much easier to install the new gasket with that added room. Looping the gasket down past the sump didn't present much of an issue. It's easy to tell when you've gotten it past the sump. From there, I just pushed the gasket onto the studs all the way around and started the locknuts onto the studs.

dr bob

John--

Can you share the failure mode of your silicone gasket? I've installed all three types on different cars, only two silicone ones though. For the MrMerlin method, it would seem almost an imperative to use the silicone gasket, so it doesn't get torn being pulled under the oil pickup.

soontobered84

My silicon gasket was leak free for 10 years. I had some buddies at a local oil change place that allow me to use their pit/lift whatever I need to use. I had taken it in to measure for replacement of the main power wire from battery to starter. The guys were all up under the car with me and we discussed how to replace that power cable. In a weak moment, I told them that they could replace that power cable. They did a great job of it.

HOWEVER, while they were doing that, they saw the different lengths of the studs from my oil pan stud kit. Of course, the nuts didn't appear to be all that tight , so being good guys, they tightened them and never said anything about it. I started having leaks and couldn't figure out what had happened until i got back under the car. The silicon was all squished out the side and, of course, leaked. I didn't say much to them about it since it was basically my fault for not supervising more closely.

As far as getting torn, I haven't dealt with a cork gasket in a while, but there wasn't any real pulling going on under the sump (oil pickup), it was more just give it enough slack and it slides easily underneath. I actually thought I might have missed it or messed up and went to pull the gasket back out and found that the gasket was already on correctly.

Aren't the good cork gaskets these days actually rubberized cork? I wouldn't think any problem would result from their use.

Herman K

Write up attached

Mrmerlin

I will add this disclamer first as it seems there is some misunderstanding going on here.

Please NOTE when adding any pan gasket to the 928 engine, without dropping the cross member

you DO NOT need to have the gasket be looped under the oil pickup.

The gasket is simply fed around the outside of the pan and fitted into position then held with copper wire strands


FWIW swapping in a new silicone gasket is easy if the MMs are in good condition,
as it will let the pan drop further away from the block.

I suggest to remove from position the following,
disconnect the battery, then drop down the alternator,
dont let it hang from its harness as the blue wire can shear.

Drain the oil,
remove the oil filter and put a towel into the filter opening,
this keeps oil from running down the block.

remove the starter, and the starter harness clamp and sway bar ,

Drop the slave cylinder from its mount on the bell housing so to move the hard line
then remove the pan bolts .

The pan will drop,
then the old gasket is removed,
use a microfiber towel with brake cleaner to wipe the pan surface a few times,
and remove the oil thats captured in the sealing surface wells of the pan.

Its also a good idea to get some come copper wire about 5 inches long,
and use about 10 strands to hold the new gasket in place.

NOTE the New gasket is simply fitted around the outside of the pan ,
so there isnt any need to fit the new gasket under the oil pickup tube inside the pan.

With all of the bolts cleaned,
add a drop of Blue loctite to the bolts then fit the 5 short bolts first,
install them a few turns then add the others.

Once all of the bolts are in a few turns,
remove the wire strands and work the bolts to final snug.

Refill the oil and refit the oil filter and other accessories.

Adk46

That's great information, Stan. Thanks.

When I did mine (as part of the MM procedure), the old gasket was 1) not leaking badly, 2) all the bolts were quite loose, and 3) the removed cork gasket was a little squashed but otherwise intact. I'm pretty sure that gently and evenly snugging up the bolts would have given many years of good service.

Depending on your situation, Vanster, you might get by with that lazy approach until your MMs go flat (and free up time for fixing your hatch release, etc.). I found that some of the oil pan bolts greatly challenged my finger gymnastic skills, even with the cross member out. And the cleaning - oh, my, the cleaning....

vanster

Great stuff, thank you all
My MM's appear to be in good shape but why not do them at the same time? I have a perplexing situation of whether or not to sell this car as I still have the 86.5 sitting in LA waiting patiently for Greg Brown to find out what is wrong with it. I can't sell this car with leaks so I am pushing hard to make it as sellable as possible, if I decide to sell it.

Bilal928S4

Stan,
Just to clarify. Are you suggesting to cut the gasket or stretch it over the outside of the pan?

Speedtoys

No..just..works it around the pan, like the tire guy works the tire around the wider rim than the tire bead is...from under the pan, not at pan gasket surface level.

dr bob

Great info Stan. dr bob, jeenious, gave no thought to installing it from the outside like that.



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I did the OPG as part of the MM exercise probably a dozen years ago. At that time, there was mention of a silicone gasket but it was only availabale from non-verifiable sources and with little or no user experience available. My previous experiences with silicone gaskets on other cars wasn't perfect, mostly because they included using the original bolts without enough tension on them to hold them in place. So they would loosen and there would be leaks. Adding a stud kit with threadlocker, and with locknuts, obviously solves the fasterner issue nicely. John's experience illustrates the need for care with using even those fasteners, as it only takes a small mis-step to force another replacement. The last few silicone gaskets put in at clinics were tightened using a cute Tomico "torque screwdriver" with a 1/4"-drive attachment, and less than 10 lbs/inch setting. That setting was determined after the first install, carefully accounting for the "breakaway" friction of the nuts on the studs as they were installed and prior to touching the pan flange. These settings are not suitable for re-use of the same nuts again, incidentally, or for studs that have oil on them. I recommend that you determine your own settings with your own hardware.

Meanwhile on my own car, I decided to install a composite cork gasket, the one with the rubber (actually neoprene) supported by cork. It's the same type that comes in the Reinz set for engine rebuild. The original gasket was cork-only. It wasn't leaking at the time of replacement, but was changed as a WYAIT task with the motor mounts and rack bushings. Over a dozen years later it's holding well. If (when) I decide to replace the Porsche MM's again, I'll replace the gaket again just as insurance.

I hate leaks.

Mrmerlin

Bilal no cutting of the gasket is necessary
The only gaskets I suggest to cut are the door edge seal,
and the mirror base gaskets.

Randy V

Very impressive, Herman! You must be an engineer in another life.