The Ford Barn

TomT/Williamsburg · 06-27-2012, 07:39 AM

I have been plagued with a rear leak on my newly rebuilt (?) flattie in my roadster (avatar). I had thought it was how I installed the pan gasket - after 3 times redoing it, I don't think so. I recently took it to the All 32 Run in Blowing Rock, NC and I had to put a 1/2-3/4 qt of oil every 100 miles - not good. Yep, this is the same flattie that has had the other issues - I'm a newbie when it comes to flattie internals and I can honestly say I'm getting "in to" flatties big time lately!

OK, I've got the engine out and on the stand - I was able to take out the cast zinc piece as per this former discussion:

http://fordbarn.com/forum/showthread.php?t=71903

and I found 2 things.

First, the rope seals were dry, both top and bottom. No traces of oil beyond the point where it meets the crank - is this normal? Engine has maybe 2K on it after the rebuild.

Second, I found that the cast zinc piece had some of the NOS style waxed paper still on it where it meets the block - so, some areas had it, other areas did not. Don't know if this was the problem but I'm thinking it's at least part of it. I've now removed all of it.

Anyhow, I'm now installing new graphite seals and Bruce Lancaster in the link above mentioned aviation permatex as a sealer - thanks for that, Bruce BTW - where would I put the sealer:

1) in the groove where the cast zinc piece resides?
2) on the ends of the rear main cap where it meets the block but not on
the ends of the seals themselves?

Despite the problems this engine has given me, it has taught me quite a bit about flattie internals - forced me is more like it - but I do enjoy doing it and I now have two other 59AB flatties I'm going to assemble that have had issues, and build a french block flattie I have as well. I've found a competent, small, and fairly local machine shop that has done flatties and all sorts of older engines to do that side of things, so I'm good there. Looking forward to this ...

My wife can't understand how I can have such patience, taking the engine out so many times - I just tell her it's all part of the challenge of building your own old car.

Thanks for any help you can give ....

JonC · 06-27-2012, 08:32 AM

I had a similar problem and after taking my oilpan off three times i was told it may be the gasket for the plate covering the rear cam bearing. I had to remove the flywheel and that is exactly where the leak was. Just a thought.

Vic Piano · 06-27-2012, 08:51 AM

Tom, I don't know just how to stop the leak at the rear main seal but if it's any consolation, I've never had a Flathead that didn't leak to some degree at the rear main seal... no matter what I did to try to stop it… Just another Ford anomaly...

richard crow · 06-27-2012, 09:30 AM

that set up you have looks like the eng could come out ez buy some of that dye you put in the oil ren eng till it leaks remove eng remove pan & flywheel you schould see where the leak is could be back plate or there is a pipe plug also could be leaking

Charlie ny · 06-27-2012, 09:32 AM

Tom,
My fresh stroker 8ba has a rear main leak, getting worse as the miles
pile up. Tell us about the graphite rope seal....where did you get it etc. That info
will be most appreciated in Sept when I yank the motor out for the 3rd time.
Hershey this year ? We're at RCB 48 - 50
Charlie ny

richard crow · 06-27-2012, 09:50 AM

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you guys say it,s normal for the seal to leak i disagre i have 7 fords not one of them leak i work pt in a resto shop when i rebuild an eng i do not get complants of the rear seal leaking i doun,t use any of those one piece front seal or any majick new seal materal . if the seal is leaking it proulby was installed wrong

Bruce Lancaster · 06-27-2012, 10:00 AM

1 and 2. The seals themselves seal by crush...any Permatex would likely be irrelevant, but I've never bothered about tips since all seals I have used were the old type soaked in oil and so unstickable. The thing should seal unless crank surface there is rough, so do worry about gear cover plate and back end of oil gallery above.
Smell the oil of course...if oil (and you) smell like a deceased whale, you are chasing a transmission problem.

deuce_roadster · 06-27-2012, 10:27 AM

Ditto what Bruce said. If you are running an old Ford trans, there have been issues with new bearings for the input shaft where the snap ring groove is slightly off and the snap ring itself is slightly thinner. All of this makes for a front bearing retainer that won't seal and trans oil pours out the front which could look like an engine oil leak. The fix for this situation is to machine down the retainer so that the bearing is held in place tightly. Of ghe 4 transmissions I have- I had to do this to 2 of them. If you can grab the input shaft and move it in and out you have this problem.

TomT/Williamsburg · 06-27-2012, 11:11 AM

Quote:

Originally Posted by JonC

I had a similar problem and after taking my oilpan off three times i was told it may be the gasket for the plate covering the rear cam bearing. I had to remove the flywheel and that is exactly where the leak was. Just a thought.

Hey, gotcha covered on this one - thanks!

TomT/Williamsburg · 06-27-2012, 11:14 AM

Quote:

Originally Posted by Bruce Lancaster

1 and 2. The seals themselves seal by crush...any Permatex would likely be irrelevant, but I've never bothered about tips since all seals I have used were the old type soaked in oil and so unstickable. The thing should seal unless crank surface there is rough, so do worry about gear cover plate and back end of oil gallery above.
Smell the oil of course...if oil (and you) smell like a deceased whale, you are chasing a transmission problem.

I'm running a 5-speed but I am checking that possibility as well - I will do/check all you have said - thanks!

TomT/Williamsburg · 06-27-2012, 11:18 AM

Quote:

Originally Posted by Vic Piano

Tom, I don't know just how to stop the leak at the rear main seal but if it's any consolation, I've never had a Flathead that didn't leak to some degree at the rear main seal... no matter what I did to try to stop it… Just another Ford anomaly...

Vic, I do not mind the usual drips and the "small" puddle of about 3" in diameter or so - it's when the puddle is 10" or more and oil is still coming out and the underside of my car is coated with oil and drips front to rear - that says there's something very wrong. It just got progressively worse as time went on so pulling the motor was my only option at this point.

TomT/Williamsburg · 06-27-2012, 11:19 AM

Quote:

Originally Posted by Charlie ny

Tom,
My fresh stroker 8ba has a rear main leak, getting worse as the miles
pile up. Tell us about the graphite rope seal....where did you get it etc. That info
will be most appreciated in Sept when I yank the motor out for the 3rd time.
Hershey this year ? We're at RCB 48 - 50
Charlie ny

I'll let everyone know, Charlie - I intend to take the car to a show in Winston-Salem July 7th - we'll see how it does.

TomT/Williamsburg · 06-27-2012, 11:22 AM

Quote:

Originally Posted by richard crow

you guys say it,s normal for the seal to leak i disagre i have 7 fords not one of them leak i work pt in a resto shop when i rebuild an eng i do not get complants of the rear seal leaking i doun,t use any of those one piece front seal or any majick new seal materal . if the seal is leaking it proulby was installed wrong

I wish you lived closer Richard, so I could bring over my engine and we'd work together on it and I'd learn how to do it properly - perfection was never my strong suit but I do try and get close ....

Karl Wolf · 06-27-2012, 12:18 PM

Taking a look at the underside of 59AB rear main cap, I have found the machining at the ends where it meets the block is machined so as to leave a narrow open slot... I put just enough silicone to fill it... Be careful where the pan gasket ends are...
Karl

flatjack9 · 06-27-2012, 01:05 PM

I doubt that you could lose 1/2 - 3/4 quart of oil in 100 miles with a rear seal leak, unless there was no seal. I would really check the cam cover in the rear.

Ken/Alabama · 06-27-2012, 02:39 PM

I always put a small bead of RTV on the diecast seal holder before I install it and put a bead under the cork strip where it fits in the cap then put the pan on there with about four bolts and leave it long enough for the RTV to cure. I then remove the pan and you can see a line pressed in the cork where the edge of the pan was resting. Put a fat bead of RTV there and in the corners where the cork strip and the pan gaskets meet. I have been doing this way for years with excellent results.

deuce_roadster · 06-27-2012, 11:22 PM

That brass screw at the end of the oil galley above the cam gear cover might be loose --if you take the flywheel off and the gasket is on the cover you should check that. Did you safety wire the cover with those special bolts with the 2 holes?
We are all curious as to what is causing your problem. Hope you find it soon, that must be getting real old.

Rascal · 06-28-2012, 12:48 AM

HI, YOU GOTTA SOAK THE SEALS IN NEW 15/40 or similar OIL FOR A DAY OR TWO BEFORE INSTALTION, ALSO THE OVAL CORK PAN SEALS WELL BEFORE FITTING TOO. ,
IF ASSEMBLED CORRECTLY YOU SHOULD HAVE GREAT SUCCESS, BUT DONT EXPECT A TOTALLY DRY OIL PAN ON A FLATHEAD, ITS A BIG ASK.

TomT/Williamsburg · 06-28-2012, 07:10 AM

Quote:

Originally Posted by Rascal

HI, YOU GOTTA SOAK THE SEALS IN NEW 15/40 or similar OIL FOR A DAY OR TWO BEFORE INSTALTION, ALSO THE OVAL CORK PAN SEALS WELL BEFORE FITTING TOO. ,
IF ASSEMBLED CORRECTLY YOU SHOULD HAVE GREAT SUCCESS, BUT DONT EXPECT A TOTALLY DRY OIL PAN ON A FLATHEAD, ITS A BIG ASK.

By the oval cork pan seal, are you referring to the seal over the rear main bearing, mating to the pan?

No, I would never expect a flathead to not leak a few drips here and there, at least not one that I did. As has been said, it's just marking its territory!

Thanks ...

Bassman/NZ · 06-28-2012, 03:21 PM

You said your seals were dry, but like the Rascal said, I've always been told they should be soaked prior to installation.

06-27-2012, 07:39 AM	#1
TomT/Williamsburg Senior Member Join Date: May 2010 Location: Williamsburg, Virginia Posts: 2,714	Rear Main Seal Leak I have been plagued with a rear leak on my newly rebuilt (?) flattie in my roadster (avatar). I had thought it was how I installed the pan gasket - after 3 times redoing it, I don't think so. I recently took it to the All 32 Run in Blowing Rock, NC and I had to put a 1/2-3/4 qt of oil every 100 miles - not good. Yep, this is the same flattie that has had the other issues - I'm a newbie when it comes to flattie internals and I can honestly say I'm getting "in to" flatties big time lately! OK, I've got the engine out and on the stand - I was able to take out the cast zinc piece as per this former discussion: http://fordbarn.com/forum/showthread.php?t=71903 and I found 2 things. First, the rope seals were dry, both top and bottom. No traces of oil beyond the point where it meets the crank - is this normal? Engine has maybe 2K on it after the rebuild. Second, I found that the cast zinc piece had some of the NOS style waxed paper still on it where it meets the block - so, some areas had it, other areas did not. Don't know if this was the problem but I'm thinking it's at least part of it. I've now removed all of it. Anyhow, I'm now installing new graphite seals and Bruce Lancaster in the link above mentioned aviation permatex as a sealer - thanks for that, Bruce BTW - where would I put the sealer: 1) in the groove where the cast zinc piece resides? 2) on the ends of the rear main cap where it meets the block but not on the ends of the seals themselves? Despite the problems this engine has given me, it has taught me quite a bit about flattie internals - forced me is more like it - but I do enjoy doing it and I now have two other 59AB flatties I'm going to assemble that have had issues, and build a french block flattie I have as well. I've found a competent, small, and fairly local machine shop that has done flatties and all sorts of older engines to do that side of things, so I'm good there. Looking forward to this ... My wife can't understand how I can have such patience, taking the engine out so many times - I just tell her it's all part of the challenge of building your own old car. Thanks for any help you can give ....

06-27-2012, 08:32 AM	#2
JonC Senior Member Join Date: Oct 2011 Location: Central NY Posts: 629	Re: Rear Main Seal Leak I had a similar problem and after taking my oilpan off three times i was told it may be the gasket for the plate covering the rear cam bearing. I had to remove the flywheel and that is exactly where the leak was. Just a thought.

06-27-2012, 08:51 AM	#3
Vic Piano Senior Member Join Date: May 2010 Location: Odessa, FL Posts: 7,611	Re: Rear Main Seal Leak Tom, I don't know just how to stop the leak at the rear main seal but if it's any consolation, I've never had a Flathead that didn't leak to some degree at the rear main seal... no matter what I did to try to stop it… Just another Ford anomaly... __________________ Imagination is more important than knowledge.

06-27-2012, 09:30 AM	#4
richard crow Senior Member Join Date: May 2010 Posts: 1,865	Re: Rear Main Seal Leak that set up you have looks like the eng could come out ez buy some of that dye you put in the oil ren eng till it leaks remove eng remove pan & flywheel you schould see where the leak is could be back plate or there is a pipe plug also could be leaking

06-27-2012, 09:32 AM	#5
Charlie ny BANNED Join Date: May 2010 Posts: 3,019	Re: Rear Main Seal Leak Tom, My fresh stroker 8ba has a rear main leak, getting worse as the miles pile up. Tell us about the graphite rope seal....where did you get it etc. That info will be most appreciated in Sept when I yank the motor out for the 3rd time. Hershey this year ? We're at RCB 48 - 50 Charlie ny

06-27-2012, 09:50 AM	#6
richard crow Senior Member Join Date: May 2010 Posts: 1,865	Re: Rear Main Seal Leak Sponsored Links (Register now to hide all advertisements) you guys say it,s normal for the seal to leak i disagre i have 7 fords not one of them leak i work pt in a resto shop when i rebuild an eng i do not get complants of the rear seal leaking i doun,t use any of those one piece front seal or any majick new seal materal . if the seal is leaking it proulby was installed wrong

06-27-2012, 10:00 AM	#7
Bruce Lancaster Member Emeritus Join Date: May 2010 Location: Madison, NJ Posts: 5,230	Re: Rear Main Seal Leak 1 and 2. The seals themselves seal by crush...any Permatex would likely be irrelevant, but I've never bothered about tips since all seals I have used were the old type soaked in oil and so unstickable. The thing should seal unless crank surface there is rough, so do worry about gear cover plate and back end of oil gallery above. Smell the oil of course...if oil (and you) smell like a deceased whale, you are chasing a transmission problem.

06-27-2012, 10:27 AM	#8
deuce_roadster Senior Member Join Date: Oct 2011 Location: Shelton, WA Posts: 3,971	Re: Rear Main Seal Leak Ditto what Bruce said. If you are running an old Ford trans, there have been issues with new bearings for the input shaft where the snap ring groove is slightly off and the snap ring itself is slightly thinner. All of this makes for a front bearing retainer that won't seal and trans oil pours out the front which could look like an engine oil leak. The fix for this situation is to machine down the retainer so that the bearing is held in place tightly. Of ghe 4 transmissions I have- I had to do this to 2 of them. If you can grab the input shaft and move it in and out you have this problem.

06-27-2012, 12:18 PM	#14
Karl Wolf Senior Member Join Date: May 2010 Location: Mill Valley,Ca. Posts: 1,539	Re: Rear Main Seal Leak Taking a look at the underside of 59AB rear main cap, I have found the machining at the ends where it meets the block is machined so as to leave a narrow open slot... I put just enough silicone to fill it... Be careful where the pan gasket ends are... Karl

06-27-2012, 01:05 PM	#15
flatjack9 Senior Member Join Date: May 2010 Location: Oshkosh, Wi Posts: 4,600	Re: Rear Main Seal Leak I doubt that you could lose 1/2 - 3/4 quart of oil in 100 miles with a rear seal leak, unless there was no seal. I would really check the cam cover in the rear.

06-27-2012, 02:39 PM	#16
Ken/Alabama Senior Member Join Date: May 2010 Location: Alabama Posts: 3,395	Re: Rear Main Seal Leak I always put a small bead of RTV on the diecast seal holder before I install it and put a bead under the cork strip where it fits in the cap then put the pan on there with about four bolts and leave it long enough for the RTV to cure. I then remove the pan and you can see a line pressed in the cork where the edge of the pan was resting. Put a fat bead of RTV there and in the corners where the cork strip and the pan gaskets meet. I have been doing this way for years with excellent results.

06-27-2012, 11:22 PM	#17
deuce_roadster Senior Member Join Date: Oct 2011 Location: Shelton, WA Posts: 3,971	Re: Rear Main Seal Leak That brass screw at the end of the oil galley above the cam gear cover might be loose --if you take the flywheel off and the gasket is on the cover you should check that. Did you safety wire the cover with those special bolts with the 2 holes? We are all curious as to what is causing your problem. Hope you find it soon, that must be getting real old.

06-28-2012, 12:48 AM	#18
Rascal Member Join Date: Nov 2011 Location: Sacto, Ca Posts: 85	Re: Rear Main Seal Leak HI, YOU GOTTA SOAK THE SEALS IN NEW 15/40 or similar OIL FOR A DAY OR TWO BEFORE INSTALTION, ALSO THE OVAL CORK PAN SEALS WELL BEFORE FITTING TOO. , IF ASSEMBLED CORRECTLY YOU SHOULD HAVE GREAT SUCCESS, BUT DONT EXPECT A TOTALLY DRY OIL PAN ON A FLATHEAD, ITS A BIG ASK.

06-28-2012, 03:21 PM	#20
Bassman/NZ Senior Member Join Date: May 2010 Location: Napier, New Zealand Posts: 2,001	Re: Rear Main Seal Leak You said your seals were dry, but like the Rascal said, I've always been told they should be soaked prior to installation.