Can't figure out this damned oil leak

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RockinRobin

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Well the front crank seal is leaking again! Is there anyone on here who can tell me which way this seal goes on the front cover of a Gen III hemi? It will install either way.
There are no instructions with the new seal, other than to install it dry and let it sit for 4 hours before starting the motor because it is that newfangled PTFE rubber.
Here is the OLD seal with the lip pointing outward:

20220918_155318.jpg

Here is the seal on the balancer with the lip pointing outward. This looks proper to me, but would be very difficult to install this way due to the lip getting curled under when you try to install the balancer over the top of it.
20220918_155206.jpg


Here is the other choice with the lip toward the motor. The balancer naturally pushes the seal out correctly over the surface, but it just looks wrong.
20220918_155235.jpg

The back side of the seal:
20220918_155309.jpg
 
The lip installs toward the engine. Two things about that seal. It's bent all to hell and it's missing the support spring.
 
After you figure out how the seal goes in, snug the timing chain cover bolts and install the harmonic balancer before you tighten the cover Down. This positions the seal evenly around the balancer.
 
Also, a light coat of RTV on the outside of the seal where it presses into the cover will assure oil does not leak there.
 
Those seals don’t need or want RTV on the outside of them. Follow the instructions as you have read with the seal.
 
Look at the ribs on the outside of it. They're usually not symmetrical, and the short leg of the rib faces the oil.

99.9% of the time, the letters on the seal can be read from the dry/out side.
 
I don't normally feel the need to explain myself but I will here since two members seem to disagree with my RTV recommendation. Here is why I do it and on any front seal, regardless of "what it's made of". There is no guarantee that the seal hole in the cover is perfectly round, just as there is no guarantee the seal is perfectly round. A light coat of RTV on the outside of the seal will assure the gap between the seal and timing cover is filled and sealed. Leave it off. I don't care. My front seal does not leak.
 
I don't normally feel the need to explain myself but I will here since two members seem to disagree with my RTV recommendation. Here is why I do it and on any front seal, regardless of "what it's made of". There is no guarantee that the seal hole in the cover is perfectly round, just as there is no guarantee the seal is perfectly round. A light coat of RTV on the outside of the seal will assure the gap between the seal and timing cover is filled and sealed. Leave it off. I don't care. My front seal does not leak.
What size of Gen III are you running? 5.7? 6.4?
 
After you figure out how the seal goes in, snug the timing chain cover bolts and install the harmonic balancer before you tighten the cover Down. This positions the seal evenly around the balancer.
Timing chain cover? What size of Gen III are you referring to?
 
What size of Gen III are you running? 5.7? 6.4?
You have my apologies. I was under the impression this was small block. My bad. However, the seal LIP still installs toward the engine. ....and I'd STILL use RTV regardless. It's just the same as a rear main seal man. The lip always installs towart the engine. The pressure of the crankcase pushes the lip against the crank and the balancer snout. Installed "the other way" and that same pressure opens the seal lip like a door.
 
The lip installs toward the engine. Two things about that seal. It's bent all to hell and it's missing the support spring.
You do understand that
1. That is the OLD seal, as stated in the original post. It was bent up during removal.
2. The new style doesn't use a spring.
 
You do understand that
1. That is the OLD seal, as stated in the original post. It was bent up during removal.
2. The new style doesn't use a spring.
Yeah some of the newer ones don't use the spring. As stated, I missed that this was a genII hemmiroid. They also have two lips on those seals from what I can tell. Maybe this will help you.
 
Yeah some of the newer ones don't use the spring. As stated, I missed that this was a genII hemmiroid. They also have two lips on those seals from what I can tell. Maybe this will help you.

Unfortunately, that video has no sound and doesn't show the seal installed. I did find one that showed the seal installed, with the lip facing away from the motor. I can see the benefit of putting some RTV on the surface of the front cover where the back of the seal seats on the cover.
 
Unfortunately, that video has no sound and doesn't show the seal installed. I did find one that showed the seal installed, with the lip facing away from the motor. I can see the benefit of putting some RTV on the surface of the front cover where the back of the seal seats on the cover.
Be very careful and make SURE which lip you install which way. I would try to find a service manual. I apologize for the initial confusion.
 
Was there a plastic seal installing device included? Is the seal surface "Teflon" ? If so, they assemble *** backwards to everything you've ever seen.
 
Was there a plastic seal installing device included? Is the seal surface "Teflon" ? If so, they assemble *** backwards to everything you've ever seen.
Now that would be a new one on me and I apologize again if that ends up to be right.
 
Was there a plastic seal installing device included? Is the seal surface "Teflon" ? If so, they assemble *** backwards to everything you've ever seen.
The rear seals have the plastic installer. I think I have it figured out now. Going to get the seal tomorrow. The surface is PTFE, which they started using when they came out with the mating surfaces that use a flexible gasket and no RTV. Apparently they use a form of this stuff in non stick cookware, so it can handle high heat.
 
I don't normally feel the need to explain myself but I will here since two members seem to disagree with my RTV recommendation. Here is why I do it and on any front seal, regardless of "what it's made of". There is no guarantee that the seal hole in the cover is perfectly round, just as there is no guarantee the seal is perfectly round. A light coat of RTV on the outside of the seal will assure the gap between the seal and timing cover is filled and sealed. Leave it off. I don't care. My front seal does not leak.

The reason i don't recommend it is because I've seen more than one seal that spooged themselves out of the bore because the RTV shears and the sealant reduced the friction holding it in place (ultra RTV is superior, but so many people use the rubber crap that doesn't stick to anything). Most seals are conformable (or at least coated in conformable materials) to accommodate inaccuracies in the bore, so that's never been an issue for me. This is why I brake-clean seal bores and seals religiously before I send 'em home. Never had an issue.
 
FYI, One more thing about these "Teflon" seals, (if that is what they are), DO NOT lube the seal surface, they go on dry.
 
Look at the ribs on the outside of it. They're usually not symmetrical, and the short leg of the rib faces the oil.

99.9% of the time, the letters on the seal can be read from the dry/out side.
:thumbsup:
 
The reason i don't recommend it is because I've seen more than one seal that spooged themselves out of the bore because the RTV shears and the sealant reduced the friction holding it in place (ultra RTV is superior, but so many people use the rubber crap that doesn't stick to anything). Most seals are conformable (or at least coated in conformable materials) to accommodate inaccuracies in the bore, so that's never been an issue for me. This is why I brake-clean seal bores and seals religiously before I send 'em home. Never had an issue.
Absolutely, I can see where that could happen if you use half the tube. LOL
 
My rule of thumb is that the part number faces out, the lip faces the oil and rtv on the outer seal.
How ever that seal has 2 lips which one is facing the oil????? If the outer part is rubber then no rtv.

Now to the op i seam to remember back when Horse Power TV was all we had, a discussion on front seal, on modern hemi.
If i recall right you had to install the seal, install the HB and then snug up 2 bolts on the seal cover. remove HB and tighten all the rest.

I have slept sence then, so i may have some of the info backwards or wrong.

This i know, is, that if you put rtv on the outer side of a rear seal on a 5.9/6.7 diesel the crank case pressure will push it back out if it has rtv or is just plainly not dry.
When instructions say install it DRY they mean both sides.

I seam to remember a story on a LS that you had to us feeler gauges on the oil pump to set it up before tightening the front cover...............I know this is not a LS but probably the same concept.

Any ways that is all i have got.
 
Absolutely, I can see where that could happen if you use half the tube. LOL

And that brings up a good point. If you was working on my motor, I'd have faith in it because you have 'commonsense'. If you RTV'd a seal, I reckon it'd be fine.

I've seen oil pumps clogged up because guys used a tube of RTV per valve cover gasket. Common sense...ain't common.
 
And that brings up a good point. If you was working on my motor, I'd have faith in it because you have 'commonsense'. If you RTV'd a seal, I reckon it'd be fine.

I've seen oil pumps clogged up because guys used a tube of RTV per valve cover gasket. Common sense...ain't common.
Oh my Lord from ZION! Remember when RTV first hit the scene? Blue was ALL there was. I've seen a Ford 302 that literally had it oozing from every single gasket joint including the head gaskets. It was awful. I was either 18 or 19 working for a small independent shop. We pulled it, cleaned it up and regasketed the whole thing. Surprisingly it was ok after that.
 
Oh my Lord from ZION! Remember when RTV first hit the scene? Blue was ALL there was. I've seen a Ford 302 that literally had it oozing from every single gasket joint including the head gaskets. It was awful. I was either 18 or 19 working for a small independent shop. We pulled it, cleaned it up and regasketed the whole thing. Surprisingly it was ok after that.
when that started we said cars like that had " The Blue Death"...
 
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