The Ford Barn

TK in LA · 11-22-2015, 02:10 AM

I'm working on a '30 "A" that was from an estate. Car is clean and shows well. After cleaning everything up and taking it for a test drive there was a large puddle under it when I parked. Suspecting the motor may be in less than great condition I pulled the pan. See pictures. Everything is clean and tight. I blew air into the rear main drain tube and it appears to be blocked. It has some epoxy/weld keeping it where it's suppose to be. Question is, if the tube isn't installed to far in and there is no obstructions seen in the threaded hole, what might be the problem? I haven't removed the tube yet so that if I do find that problem I won't have to stop and jump onto the computer. If I had the motor out this wouldn't be a problem.

Mike V. Florida · 11-22-2015, 02:35 AM

http://www.antiqueenginerebuilding.c...RMAINLEAK.html

Tom Wesenberg · 11-22-2015, 07:17 AM

It's easy to remove the rear main because the heads of the 2 bolts are locked to the block by a flat side. I'd remove the rear main cap and have a good look. Remove the steel disc if you need to so you can check the path of oil drainage. Maybe some babbit is blocking the path.

BTW, what's the history of the engine.........recent rebuild, or?

2manycars · 11-22-2015, 08:16 AM

If you take off the rear main cap. pay attention to any shims that are present, and be sure to return them to the same side they came from.

jw hash · 11-22-2015, 10:23 AM

Remember oil does NOT run up hill. looking at your oil return tube there appears to be a leak up there. also look for any clean oil up between the back of the block and the flywheel housing. and like Tom said it is easy to remove the rear main cap and check that out while you have the pan off.

Patrick L. · 11-22-2015, 11:22 AM

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With the rear cap removed, I'd recommend checking the clearance. As long as you're there, why not. Too much clearance can cause it to leak. I prefer to set the bearings a little snug at .0015" and the rear main at .001".

Also another thing to consider is the rear gasket. Sometimes its not installed and the camshaft can then leak like crazy.

I ran into [ well, met] a fella one day some time ago while he was looking over the 'A' and saying he had a 31 and his 'new' engine had a badly leaking rear main seal. He didn't know what style 'seal' he had, but, was about to remove the engine. I mentioned the rear gasket and he said he wasn't aware of and didn't install one. I gave him my phone number to call once the engine was out if he had any problems. Haven't heard from him. Figured the leak is now fixed.

Jim Brierley · 11-22-2015, 12:32 PM

.030" on the mains, .020" on the rods, not bad!

hardtimes · 11-22-2015, 01:06 PM

Quote:

Originally Posted by Jim Brierley

.030" on the mains, .020" on the rods, not bad!

Hey Jim B

,
Is that.... .003 mains and .002 rods ?

TK in LA · 11-22-2015, 02:05 PM

A nice warm Sunday morning in SoCal to spend under the Model A. After improvising a modified socket to get the 3/4 nuts off I see that someone installed a rubber seal to the crank. This may be part of the problem with the restriction and the leak? The rear main has some pour pitting in the surface but nothing to be concern with right now. The main had the oil groove done with a rotary ball debur that's not pretty but should be OK. Clearance on the main is right at .0015. No restrictions in the line from the main to the tube. My guess is that when I blew air into the drain line the seal kept the air from exiting the main and the bearing is tight enough to keep the air from going back into the valve chamber?
JW , the first thing I did was check the oil from the valve chamber drain tuber and side gasket. Both were loose but I observed them and the side of the block before removing the pan. Leak was very minimal. Any suggestions on sealing the rubber seal. I'm not going to remove the engine to replace it.

hardtimes · 11-22-2015, 02:14 PM

Hey TK,
Looks like in (third)picture, that seal has a small distortion on left side ?
And, in fourth picture, I do not see any type sealant (silicon) at outer corners of seal where is enters cap. Usually a SMALL dab of sealant on those two areas helps prevent leaks from those spots ?

TK in LA · 11-22-2015, 02:18 PM

Hardtimes, There is nothing that I can see that sealed the seal to the block or the cap. The seal spins freely with some minimal resistance as it sits in the picture.

hardtimes · 11-22-2015, 04:00 PM

If this orange colored paint is 'glyptol', I've never seen it used like this engine shows. I'd clean that off of mating surfaces, as it could/would cause unwanted and unintended consequences and clearance problems

Mike V. Florida · 11-23-2015, 01:22 AM

Quote:

Originally Posted by TK in LA

... I see that someone installed a rubber seal to the crank. This may be part of the problem with the restriction and the leak?

Quote:

Originally Posted by 1930 coupe

Those rubber seals were a big fad a few years ago. They are very difficult to install properly, and then they did not last very long until they started leaking. You usually have to remove the crankshaft to install it properly, then it will start leaking again after a couple of years. Many re builders are getting away from modified rear seals and going back to stock slinger systems..

I think 1930 Coupe is correct, it is your problem.

Dodge · 11-23-2015, 01:57 AM

I also don't see any oil wells in the rear cap.

TK in LA · 11-24-2015, 07:02 PM

Tried sealing the rear seal with gaskeacinch like the instructions on the web site state and the rear main along the sides of the cap. Put everything back together and it still leaks, not as bad but it's still there. Short of pulling the motor that's it for now. Thanks to everyone that chimed in with suggestions. Just more experience that hopefully will help someone else down the line. Have a GREAT Thanksgiving!

11-22-2015, 02:35 AM	#2
Mike V. Florida Senior Member Join Date: May 2010 Location: South Florida Posts: 14,054	Re: Another rear main question http://www.antiqueenginerebuilding.c...RMAINLEAK.html __________________ What's right about America is that although we have a mess of problems, we have great capacity - intellect and resources - to do some thing about them. - Henry Ford II

11-22-2015, 07:17 AM	#3
Tom Wesenberg Senior Member Join Date: May 2010 Location: Mpls, MN Posts: 27,582	Re: Another rear main question It's easy to remove the rear main because the heads of the 2 bolts are locked to the block by a flat side. I'd remove the rear main cap and have a good look. Remove the steel disc if you need to so you can check the path of oil drainage. Maybe some babbit is blocking the path. BTW, what's the history of the engine.........recent rebuild, or?

11-22-2015, 08:16 AM	#4
2manycars Senior Member Join Date: May 2010 Location: Eastern CT Posts: 2,732	Re: Another rear main question If you take off the rear main cap. pay attention to any shims that are present, and be sure to return them to the same side they came from.

11-22-2015, 10:23 AM	#5
jw hash Senior Member Join Date: May 2010 Location: Auburn Washington Posts: 2,552	Re: Another rear main question Remember oil does NOT run up hill. looking at your oil return tube there appears to be a leak up there. also look for any clean oil up between the back of the block and the flywheel housing. and like Tom said it is easy to remove the rear main cap and check that out while you have the pan off.

11-22-2015, 11:22 AM	#6
Patrick L. Senior Member Join Date: May 2010 Location: Largo Florida Posts: 7,225	Re: Another rear main question Sponsored Links (Register now to hide all advertisements) With the rear cap removed, I'd recommend checking the clearance. As long as you're there, why not. Too much clearance can cause it to leak. I prefer to set the bearings a little snug at .0015" and the rear main at .001". Also another thing to consider is the rear gasket. Sometimes its not installed and the camshaft can then leak like crazy. I ran into [ well, met] a fella one day some time ago while he was looking over the 'A' and saying he had a 31 and his 'new' engine had a badly leaking rear main seal. He didn't know what style 'seal' he had, but, was about to remove the engine. I mentioned the rear gasket and he said he wasn't aware of and didn't install one. I gave him my phone number to call once the engine was out if he had any problems. Haven't heard from him. Figured the leak is now fixed. Last edited by Patrick L.; 11-22-2015 at 01:35 PM.

11-22-2015, 12:32 PM	#7
Jim Brierley Senior Member Join Date: Jun 2010 Location: Temecula, CA Posts: 4,095	Re: Another rear main question .030" on the mains, .020" on the rods, not bad!

11-22-2015, 02:14 PM	#10
hardtimes Senior Member Join Date: May 2010 Location: South California Posts: 6,188	Re: Another rear main question Hey TK, Looks like in (third)picture, that seal has a small distortion on left side ? And, in fourth picture, I do not see any type sealant (silicon) at outer corners of seal where is enters cap. Usually a SMALL dab of sealant on those two areas helps prevent leaks from those spots ?

11-22-2015, 02:18 PM	#11
TK in LA Senior Member Join Date: May 2010 Location: La Verne, Ca. Posts: 828	Re: Another rear main question Hardtimes, There is nothing that I can see that sealed the seal to the block or the cap. The seal spins freely with some minimal resistance as it sits in the picture.

11-22-2015, 04:00 PM	#12
hardtimes Senior Member Join Date: May 2010 Location: South California Posts: 6,188	Re: Another rear main question If this orange colored paint is 'glyptol', I've never seen it used like this engine shows. I'd clean that off of mating surfaces, as it could/would cause unwanted and unintended consequences and clearance problems

11-23-2015, 01:57 AM	#14
Dodge Senior Member Join Date: Nov 2011 Location: Sonoma, CA. Posts: 1,498	Re: Another rear main question I also don't see any oil wells in the rear cap.

11-24-2015, 07:02 PM	#15
TK in LA Senior Member Join Date: May 2010 Location: La Verne, Ca. Posts: 828	Re: Another rear main question Tried sealing the rear seal with gaskeacinch like the instructions on the web site state and the rear main along the sides of the cap. Put everything back together and it still leaks, not as bad but it's still there. Short of pulling the motor that's it for now. Thanks to everyone that chimed in with suggestions. Just more experience that hopefully will help someone else down the line. Have a GREAT Thanksgiving!