Hi.
I have a new engine 350 with a 1pc main rear seal. (crate engine)
The engine is from 97 but it never has been fired-up, I did a complet dismantling and clean all the parts and put there some fresh engine lube and check all the specs where correct.
Did change the crank bearings too.

The problem.
Now a couple days ago I decided to check the oil pressure by a hand drill, after 5 seconds the gauge was giving 70 psi and that is good, so I continue pushing with the drill to get oil at the rockers, it took 20 minutes to have oil at every rocker (crank turning by hand) and a smoking drill (poor baby, it did suffer a lot)

Any way I was happy because I have the oil at the rockers and the right pressure.
But after check under the car I found a spot (5" x 5") of oil that comes from the bell housing and inspection plate.

Oil pan was dry.
Gearbox don't have oil in (it is new)
So the conclusion is that the Main rear seal is leak.

My question is or are:
- Do you have had this experience?
- Does this happens because the engine don't run and don't have vacuum?
- Do you think that if I run the engine the problem will be solved?

Any advise is welcome.

Best regards,
Cobra289

 

Pull the seal out and check that the lip didn't get folded over during installation.

 

Hi Apeiron,

I hate that! It is possible that the lip was folded.
But do you think that the vacuum theory has a change?

I will need to remove the engine and the gearbox to get at the flywheel.

The engine is installed at a Cobra replica and there is no room to move the box a bit to the back to get access, so it would be a pig job, no lifting facilities etc.

I was all most there and did plan to fire it up at the end of august.

Regards,
Cobra289

 

Vacuum has nothing to do with it. In actuality with a PCV system, you might have 1 or 2 PSI of vacuum in the crankcase. Even if you had a perfect vacuum inside the crankcase, that's only about 14.7 PSI of pressure pushing in. The oil pressure is still pushing out with 55 PSI more than that.

 

Hi,
It is clear I need to walk the shame path and renew the seal.
I think that this is better than dismantle the aluminum holder, because this last will imply remove the oil pan too.

I did install the set (holder and seal) when the engine was at the stand and probably, due to the reduced access I did fold the lip to the outside.
Check the picture.

Regards,
Cobra289

PS
I don't get the instant email notification, is there a delay due to Europe?

 

Perhaps this picture is better.
I think that I see the lip pointing rearwards and that is not good.

Bah! pig job to do.
Thanks!

Regards,
Cobra289

 

Kinda hard to see anything in the pics, but it's a good chance that's what happened. When I install one, I always make sure to smear a light coat of engine oil the the lip of the seal, and when you first start to slip it over the round part of the crank, twist it some while you're pushing it into the aluminum holder. That helps prevent the lip from folding over.

 

Hi Pat,
I know what you mean.
I did it wrong because the engine stand was in the way, so I think that I did push without watching the lip position.
It was coated with grease.

One question.
Do you think that if I can manage to get just a bit of room there to access with a plastic o wood pry rod, that I can fold the lip back to the right position?

It is a new seal, so I think that can have some force but perhaps the tolerances doesn't allow to fold it back.
A new seal has been order by Summit and it will take some time to get it here in Holland, but just in case.

What do you think?
You know I try this way because I don't have any engine lifting facilities.

Regards,
Cobra289

 

once you fold a lip over on a seal it usually leaves a nice crease and couple of small cuts and will never seal again.

if your working with close spaces the best way is to start the seal and spin it slowly and then fully press it on. and dont forget to lube the seal

 

I hear you, but in my case the engine didn't run yet, it was rotated just by hand.

I will try when the new seal is in to install it with some care, rotate and pull out a bit one that it is settle push till the holder, of course engine oil will be apply this time, I think that it would be lots better than the original grease.

Thanks,
Cobra289

 

I can relate to your problem with trying to install the seal with the motor bolted to a stand. I hooked my engine hoist to the motor, unbolted it from the stand, then carefully lowered it to the floor to allow plenty of room to put the seal in. I actually installed the seal into the aluminum holder while it was sitting on the workbench. Then I put a little engine oil on the seal, a light coat of rtv on the flat gasket that goes between the block and the aluminum holder, then carefully twisted the assembly over the crank surface and torqued to spec. I stuck it back on the engine stand after I got the seal installed successfully.

 

Hi all,

Just a nice feedback, the problem has been found and solved.

Today I went to my Cobra (Powered by Chevy) to have a real inspection of the leak.

After removing the inspection cover, I found that the inside of the bell housing was dry and the aluminum seal holder too.
I was perplex, where the hell the oil comes from?

Lucky, the engine and box are new and therefore the surfaces are clean.
I found the track of oil only at the bell housing flange guiding me till the filter but it wasn't the oil filter.
Climb up there is a horizontal recess, there where the casting numbers are located and I found there a pool of oil (that was feeding the bell housing flange)

Follow the wet oil track, difficult to see but with some LED light the reflection change and was possible to trace.

Finally it guides me till the top of the China Wall there where the Oil pressure Gauge was temporary hock up.

And yes it was the compression fitting at the connection that leaks, it was closed only finger tight and forgot to give an extra turn at the nut.

So we cleaned all the oil tracks and traces and we pressurized the oil and guess what? this time the oil pressure went to 75 PSI instead of the previous 70 PSI, at that moment I was very please because this give me a good indication of the leak was solved.

After several times of putting the engine under pressure with the drill machine we could not find any leak.
So we can conclude that we don't have to change the rear main oil seal.
And that is a relief because other the engine should come out and with out the right hoisting tools it would be difficult.

Anyway, thanks for your cooperation and interest. I have appreciate it.

Today we did learn a two lessons, never think to fast for the worse situation and oil leaks can appear at spots that are far from the origin.

Best regards,
Cobra289

 

Ahhh yes, the ever popular leaky oil pressure line! Been there a few times too. I'm betting you have the nylon tubing huh? They can be a real PITA to get the ferrule crimped right to where they don't leak sometimes. In fact, I keep a proper size pipe plug in my console just in case mine ever develops a sudden leak. I blew the line out of the fitting when I was out street racing one night. Man, talk about a mess! Oil everywhere and smoke barrelling off the header tubes. Glad to hear you figured it out, and it turned out to be a much simpler fix than replacing the RMS.

 

Hi Pat,
Yes it turned out that is was an easy one.
I never had expected to have so much oil at the floor by the little NYLON tubing.
During the engine build I did install the NPT fitting and top of with the nylon compression fitting, but to protect the internals I put there some tape and that tape, left some tracers at the thread, that was the reason why my son did not put to much pressure, because we know what happens with the ferrule when you over torque it, been there long time ago.
In fact it is a good advice to have one of those little things plus a cap somewhere at the car, just in case. Easy to fix in a minute if you are underway.

Thanks for your help.
Regards,
Cobra289 (Carlos from the Netherlands)