hosrom_951

I asked a fellow rennlister regarding this, but i need more views/opinions.

I believe that both driver's and passenger sides of the balance shaft covers are leaking (saw the passenger side for sure).

A quick fix is to clean out that area and apply some loctite. Going through the manual, you could re-torque the bolts to specifications.

However, what is interesting is that there are no gaskets, seals (for the cover not the bolts) or loctite that is used by the factory. It is basically metal on metal contact so..........

Did anyone here sprung a leak from the balance shaft covers and actually took it off/re-torqued the bolts or even apply loctite to the bolts ???

TIA

M758

I re-did the rear o-ring and used loctite sealant on the surfaces. Loctite 571 I think.

joseph mitro

factory manual says to apply loctite 574 (red) to both balance shaft covers before installation.

hosrom_951

Just went through the manual once more, couldn't find anything regarding loctite, maybe i have a page (or two) missing.

M758: Which rear seal? is it seal number 22 on the illustration?

Joeseph: Again, where do you see the manual stating using loctite? and would all the hex bolts require new seals (washers)?

F18Rep

I had the leaky balance shaft covers too but mostly at the small quarter-size o-rings (at the rear of the cover). These O-rings had shrunk so much (I guess from heat and age) that the little caps could be wiggled around eventhough all the cover bolts were tight. I fixed the leak by removing the covers and resealing per the manual (although I didn't use the loctite stuff, I used some flange sealer that seams to have done OK - so far).

Porsche seems to go with a gasket only as a last resort.

joseph mitro

i'm not at home so i don't have the manual available. i'm almost positive it states to use loctite in the section referring to installation of balance shaft covers. maybe i heard it on here also.

the only washers needing replacement is the seal for the plug on the upper cover.

hosrom_951

F18: Yeah, i have a very minor leak (it's wet, nothing serious yet) but from both driver and passenger sides.

Thanks for the image, now does the rear seal come off along with the cover (once the cover is removed, the seal comes with it?)

I need to order some parts, so i need to know what to do. The only thing now is a torque wrench and a lift unless there are any tricks here or there......

Granite 944

Heres a picture from a engine that’s currently on my engine stand, but was in my ’85. I was chasing oil leaks back then, and at one point, used a red RTV silicone to seal the rear cap, and at another time, blue RTV to seal small leaks coming out of those two bolt holes. I did not remove the cover of course (way to much work, for the time and circumstance). I would recommend doing the same. I’ve actually done this on 3 different engines now. The key to doing this is that the surfaces MUST be clean as a whistle, or the RTV will not adhere and seal up. The only place I’ve seen that calls out to use the Locktite 574, is in Clark’s garage writeup on the balance shaft seal section. I agree with doing this, but I would only do this if/when I had real good access to the balance shaft housing, and the situation was worthy of it. If your leaks are actually coming from between the housing mating surfaces, you may have no choice but to completely remove and reseal the housings. Clean your engine off real good around those areas, run the car a while and make sure of where all the leaks are coming from. You most likely will end up doing this type repair that I’ve done, instead of removing and then resealing the housings. Its not pretty, but it works. " Re-torquing" these bolts, without removing them completely and cleaning up the threads, will most likely do you no good at all. One other thing, personally, I wouldn’t use any type of locktite on the threads of those housing bolts, at anytime, or for any reason, unless you really want that PITA, when its time to remove them, the next time. Good luck!

hosrom_951

Mr. Ken,
Im shooting for removing the balance shaft housing cover. An i agree, there is very little room and it could be a real pain and much work to do. But id rather do the job right once than do it twice (or more) for a poor job. I shall watch out and make sure that all mating surfaces are clean and dry before applying loctite.

My question was weither or not there was a gasket or a seal for the housing since i still do not see (read) where in the manual it states that loctite would be used. But again, removing , cleaning and loctiting the balanance shaft housing cover tips is appriciated.

What about the rear seal, is there a bolt that holds it or would it just slip out when the cover is removed?

Thanks

Granite 944

Hussam, I really can appreciate your view when it comes to "rather do the job right once than do it twice (or more) for a poor job." I agree, and admire it.
I must admit, I've never pulled either of these housings off, while engine is complete, and still in the car. It really does not look like it would be any fun.

As far as a "gasket" goes. To my knowledge, Porsche never used a gasket under these housings. I know, I've not seen one under any of these housings in the 2 engines that I've completely stripped down, and I haven't seen a listing anywhere for one. The rear seal in these housings, amounts to being a large, wide O-ring. The cap that the O-ring goes around, fits in an area, wedged between the two housing halfs, and will fall out once the housing halfs are seperated. My pic below shows the lower balance shaft assy. just laying in its position on an engine thats apart, and laying on my garage floor. There is a rear seal cap with the red O-ring still located in the block half, and the one from the other balance shaft, laying up next to the lower/outer housing which I put up there for reference, with the O-ring taken off. In dismantling this, you will want to have the Locktite 574, new O-rings, and possibly all the front seals for these shafts also. You might get away with not needing the front seals (large O-ring in particular), if your really careful when taking the outer housing off.
Like I said, I've never removed these outer housings, while in the car. Only when completely out of car. Also see http://www.clarks-garage.com/shop-manual/eng-14.htm for more reference. Good luck.

hosrom_951

Mr. Ken,
Thank you, this would be my first time replacing a seal on the car. Im going to pass by my dealer and see if he has the rear balance shaft seal (they don't stock much 944 parts due to only 4-5 of these cars are in the country).

Again, thank you once more for informing me on the rear seal removal. I shall tackly this job on Thursday-Saturday (yeah, between Christmas eve and Christmas ) but at least it would stop that leak

hosrom_951

Mr. Ken,
Two last questions, first after cleaning the area after removing the cover, this is where i apply loctite correct (i used you picture if you do not mind):



Offcourse, i would avoid putting loctite in the bolt (thread) holes, and i would also apply loctite to the cover, or that is not neccessary?

Secondly, i would only need the two rear seals (for both sides), i would not need a new cap (or ring as the PET system shows) correct?

Thank you once again for all these questions.

Hussam

951Tom

Hosrom, apply loctite completely where both surfaces meet and around the bolt holes. Your line on the bottom looks a little off in one area. The metal end caps will fall right out once the cover is removed. They have to be in place before the cover goes back on don't forget. With the drainage holes down to the crankcase, could these rear cap o-rings cause a vacuum leak??

I used high-temp red Permatex sealant 3 years ago when I resealed my upper balance shaft housing and it hasn't leaked a drop since. Used a new o-ring from the dealer for the rear cap & torqued it down properly.

AlexE

Hosrom........Yes you use 574 to seal it. No other seals except the rear and front seals.
Loctite 574 is an anaerobic sealer. Go ahead and apply on the housing and the block side. THe mating surfaces must be spotless. The loctite will not set until you have the housing torqued.
Also when re-assembling, the housing and the block get torqued together first ........ then the front balance shaft housing is supposed to be torqued in to place.

P.S I can't imagine doing this job with the engine in the car..... specially if its a turbo.

Danno

Dont' forget that in order to remove the balance-shaft covers, you have to remove the entire front-end of the engine, all the belts and belt-covers.

ALso replace the front-seals while you're there. You'll need the O-ring type-seals, the onion-skin mylar ones as well as the outermost seal that's of two different sizes.

You might as well replace the balance-shaft bearings while you're there. Be VERY, VERY careful to mark the bearing-cap so that you do not install it back up-side down. It will go back in with either orientation, but will only correctly fit one way. If it's reversed, it'll bind the bearing, the actual amount varies between engines.

If it's only a minor leak, I would do what Ken did on his car. I prefer to use a hard epoxy on the right side to deal with the heat from the headers.