Leaking Oil Pump cover

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Glen Getchell
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Re: Leaking Oil Pump cover

#16 Post by Glen Getchell »

Actually I thought of the bolt being to long. I measured the hole and the bolt, and it was really close. So before the last attempt I pulled it and cut a couple of MM off of it. I can't be sure if it helped or not because I have had it on and off so many times, and because I can't remember crap anymore they are all blurring together. But, I do remember the last two installs. Brand new Stoddards Gasket modified to Vic's pump. Installed dry. Ran with no leaks. Shut the car off, and there is a puddle (It really does look like it is coming from the plate, and I have stared at it for long periods). Thinking that maybe It just needs to be tightened, I did so (after they are hot, there always seems to be a little more cinching up that can be done). After that I had a "true" leak while running and after turn off. I then took it apart, inspected and measured and cleaned up the gasket. I could see no reason not to attempt it again with the same gasket as I have a finite number left, and it had literally been used for 10 min. This time I installed. Again, no leak while running. Leak while off (That slowly stops after turning engine off). This time I did not cinch up the nuts. Numerous runs has the same result. No real visible leak when running, enough to spot the floor after shut off. Then no more leak.

I have tried a goo version of the suggested Hylomar idea (I literally could not find that stuff locally. At least by internet search). So I used some stuff that I did have had last night, since it needed time to cure. We'll see today if that is enough to stop or reduce the drips. If it even cuts the drips by 50%, it would just be become a nuisance at best.

Glen
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Ashley James
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Re: Leaking Oil Pump cover

#17 Post by Ashley James »

Loctite grey part number 5699 seals up to 1mm gaps, there’s no downside, or not in the thirty or more years I’ve used it.

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Glen Getchell
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Re: Leaking Oil Pump cover

#18 Post by Glen Getchell »

Ok, goop "kinda" worked, "kinda" didn't. Last night in my in my Pajamas I only gooped the sides and bottom as the top is behind the tin and pulley (didn't want to get grease in bed. Some part of the house has to be clean). Well no leak from the bottom of the plate, instead the leak is coming from the top now, and then is flowing down both sides and dropping off of the two corners rather than the middle as it did before. So I gooped the top tonight, and I'll see what happens. The funny thing is that basically it was still four drips and a hanger even though it was visibly obvious the oil is coming from above instead of the bottom as before. The real issue is those four drips leave a nice oil spot on the concrete.

The only thing I can think of is that some how there is residual pressure left in the system. And because the pump is not on, the oils is not being sent around the little oil groove. I have no idea if I am right or not, but at this point I think I would rather duct tape rags to the bottom before pulling it apart for this issue. No I am not lazy (ok, that's a lie). The truth is that I had to deal with Florida Machine shops for a freaking year! Trust me, this can cause serious health issues. In fact, I have heard 50% of all suicides in Florida are car guys who needed a machine shop. I think I saw it on the Internet, so it must be true! And to think, my Father was a tool maker. When I was a kid and broke a toy, I just put part in his work shoe. By the end of the week, I had a new hand built part (usually made from stainless). Now if they can't just put buttons on a computer, good luck! Oh, and they are called "Techs" now. A word meaning (I know how to push buttons on a computer). But I digress.

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Dick Weiss
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Re: Leaking Oil Pump cover

#19 Post by Dick Weiss »

Glen,

Your statement of oil being sent around the little oil groove is incorrect; Make sure the cover's gasket has its hole lined up to the hole
in the cover which 'w/draws' the oil from the surrounding groove back into the system; The gasket only goes on 1-way--tach drive or not.

The other possible leak from above will be coming from the pulley seal. Check it's hub for wear or pitting; I refinish those, too.

Dick

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Glen Getchell
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Re: Leaking Oil Pump cover

#20 Post by Glen Getchell »

Dick,
As you said, the gasket will only go on one way, and I am on my fourth gasket. The third piece "looks" to be in good shape (though its a new part for me), and the cover plate was used on the last engine for over 10-15 years without an issue.

As to the rear seal, I believe there is some weeping there. I'm sure taking the pulley on and off a million times is not helping that. But it really looks like the oil is coming from the oil pump cover. And the fact that the flow of the oil changed after I sealed the bottom further makes me believe it is the pump cover.

Due to that annoying thing called work, I have not had time to start the car and heat it up to see if the goop on top of the cover has stopped or slowed the leak. I'll update once I do.

Thanks!
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Re: Leaking Oil Pump cover

#21 Post by Ashley James »

Hylomar and Wellseal are WW2 technology, modern silicones are infinitely more effective as long as you use the correct one for the job.

Have a look at the Loctite website for advice if you’re not sure, having first made sure the lid isn’t bowed.

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Martin Benade
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Re: Leaking Oil Pump cover

#22 Post by Martin Benade »

I thought the pulley seal idea sounded likely as well. Maybe sealing the bottom just altered the flow of oil coming from elsewhere. Pulley seals have a lot more tricks up their sleeve than paper oil pump gaskets in my experience.
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Dick Weiss
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Re: Leaking Oil Pump cover

#23 Post by Dick Weiss »

Another possibility; Is the sump plate assembly wet? If so, oil will be traveling rearward via air flow during a drive and also 'wetting' the muffler/exhaust system. Be sure to clean everything off as best as possible!

Run the engine/car (when standing still) for 5-10 minutes, then shut it off & look from where it's leaking.

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Re: Leaking Oil Pump cover

#24 Post by Rusty Ferrell »

Glen, I’ve used a dye in the oil to find location of leaks. Ultraviolet light and sometime glasses will reveal the leak. I warm up the oil clean everything with brake clean then add the dye run the engine while looking for the dye in the oil. Just a suggestion. Let the engine tell you what is wrong as long as they can run they will talk to you. Good luck
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Glen Getchell
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Re: Leaking Oil Pump cover

#25 Post by Glen Getchell »

Ok, here is my update. Going back and gooping the top of the oil pump cover as I had the sides and bottom previously has stopped the leak. This confirms what I was nearly 100% sure; that it was indeed the oil pump cover. and not the rear seal. My belief was based on a lot of time watching the leak, and the fact that when I cinched up the oil cover nuts the leak got much worse. Now no oil on the floor. Yipi!

I have no earthly idea why it would only leak after the engine was turned off if my previously mentioned theory was wrong per Dick. But the leak has stopped (or is at least contained with the sealer).

What I did to stop it was use a RTV type sealer I had bought a while back for transmissions when I re-did the transaxle. Cleaned everything then put a nice smooth layer around the mounting gap. Now no leak. Best part is it is the same color as aluminum, so nobody will ever know. Well except the entire 356 community who reads the forum. See I'm clever like that!

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Martin Benade
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Re: Leaking Oil Pump cover

#26 Post by Martin Benade »

You sealed it externally, without removing the pump cover once again?
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Re: Leaking Oil Pump cover

#27 Post by C J Murray »

Martin Benade wrote:You sealed it externally, without removing the pump cover once again?
I bet I know what you are thinking Martin.
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Re: Leaking Oil Pump cover

#28 Post by Glen Getchell »

Yes!

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GregVandenbussche
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Re: Leaking Oil Pump cover

#29 Post by GregVandenbussche »

Hi Glen,

there is also two small pins sometimes on the oil pump cover, they match two small holes on the third piece, if one of the pin is not matching properly, or if the hole is damaged/filled up with stuff you could end up with the cover not sitting flat.
Reading all your post i feel that your gear end play is little too tight, when the engine warms up aluminum expand more than steel and therefore reduce the interference, when it cools down the gear "push" again on the cover... might be wrong but my cover is sealed with two custom made thin gasket made with paper groceries bag (for proper thickness) with a super thin layer of Curil T and no oil to be seen.
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Glen Getchell
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Re: Leaking Oil Pump cover

#30 Post by Glen Getchell »

Greg,
I know the pins that you are referring to, but I have never seen them on the later "Electric tach (no tach cable) covers". In fact I have one sitting on my desk right now and there are no pins. And while these days I would not even guarantee I wrote the previous sentence, I am pretty sure that Vic's pump cover has no pins either.

As to the pump clearance. It is always a possibility, but everything was done to avoid that prior the installation. Everything was measured a million times over. Gears were removed from shafts and flipped around per Dick's advice. A shaft with a better tang was used, etc... In the end, the finished oil pump was in spec. The slightly worn side of spec., but spec non the less. So while possible, I would be surprised. In addition when I had run out of gaskets, I tried my own while I awaited my Stoddard delivery. It was close, but still slightly thicker than it was supposed to be. The results was the same. So I think if it was just a hair off, that gasket probably would have made up for it. I also had the entire pump out during one of the many attempts to stop the leak, and saw no unusual signs of rubbing or binding. If anything, if the pump "is" sticking out to far, it could be the new cam. I did not measure where the timing gear bolts to the new neutek cam. But again no indications beyond the weird leak that anything is wrong. Maybe I made a mistake by not measuring that, but it never even occurred to me to do so. But I think if that was the problem it would leak all the time.

I'm sure if I'm wrong about any of this, I will find out shortly after hitting the track. I really hope I'm not wrong! But absent signs of something clearly wrong, I can't see pulling and opening this engine up again for something that appears to have been cured. Again, I really hope I'm not wrong!

Glen
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