rear main oil leak on 482

[daryl w66]

Sorry for the long post. I had a 482 built for me in 2005 from a well known engine builder in the southern us. I have had a few life challenges since 2005 that's why there is hardly any miles on it. There is about 400 or so miles on it, no racing. Genesis iron block ,elderbrock alum. heads, 2x4, scat stroker crank, diamond pistons, comp cams hyd. roller cam, erson roller rocker setup. The paperwork from the builder said no warranty for rear main seal leaks. They never discussed this with me when I was ordering engine. Engine has leaked oil out of rear main seal area almost from day 1,but only a tiny bit when 1st ran. Noticed a few drops under car after shut down. Anyways, after I had drove it a bit, leak got a little more. I had a local mechanic who knows these engines well, he has a couple of stock ford 427 and 1 he used to race, to change the rear main seal for me. He changed the seal 3  times and the oil leak got a little bit more each time. He said he tried every method he knew. He checked everywhere else on the engine to make sure oil leak wasn't coming from somewhere else. He even used dye. I guess I won't know for sure until engine is out of car. It now leaves a small puddle every time I have ran it. He told me that the next step is to pull engine out and take it to an engine builder to pull apart to fix oil leak. He then retired and moved away and I don't know any other  fe mechanics around here. Since then I have learned about scat cranks, early fe scat cranks coming with no grooves cut into rear of crank to help oil from leaking out of rear main seal. I learned this from reading the definitive guide to fe rear main seal install posted on this forum a while back. I'm guessing that my year 2005 scat crank in my 482 has no grooves cut into rear of crank, contributing to my rear main oil leak. I'm gonna pull engine soon to try and get this fixed. I'm assuming engine will need complete tear down, if this is indeed the source of the leak, remove crank  to get machined rear grooves cut in, inspect  all other parts and put back together with new bearings, seals and gaskets. Dyno test engine to tune it. I am no engine builder but know  a bit about fe motors. ? #1- Does this sound about right to fix my oil leak if it is rear main seal leak ? Any help or suggestions from this forum would be greatly appreciated . ? #2- I 've read posts here from members who are in the vancouver, b.c., canada area. Could any members from there recommend an engine builder, machinist in the vancouver,b.c. area that can do this work for me or do I have to look down in the u.s. to get this work done? Engine is in my 66 fairlane 4- speed. Thanks!     

[Cyclone03]

I had a multi year,multi seal rear main leak. The “fix” came after a refresh due to a broken cam.
I can only tell you what I did and going on 3 years I’m just now getting oil on the outside of the pan,but no drips yet.
My feeling was the leak is from the three surface block/head/intake junction . My last head install right at the junction I put a dab of sealant on both sides of the head gasket at all four corners as well as top and bottom of the intake manifold gasket then of course the front and rear “China wall”. This is only right at the junction to the China wall.

Also when I installed the intake I did the same at the valve cover rail,both sides of gasket.

For 2 year the outside of the engine was oil free,like I said it’s come back a bit.

I’ve had valve cover gaskets leak too with oil around the plugs and around the back of the heads.

[brettco]

I had a multi year,multi seal rear main leak. The “fix” came after a refresh due to a broken cam.
I can only tell you what I did and going on 3 years I’m just now getting oil on the outside of the pan,but no drips yet.
My feeling was the leak is from the three surface block/head/intake junction . My last head install right at the junction I put a dab of sealant on both sides of the head gasket at all four corners as well as top and bottom of the intake manifold gasket then of course the front and rear “China wall”. This is only right at the junction to the China wall.

Also when I installed the intake I did the same at the valve cover rail,both sides of gasket.

For 2 year the outside of the engine was oil free,like I said it’s come back a bit.

I’ve had valve cover gaskets leak too with oil around the plugs and around the back of the heads.

  are you using a pcv system or just breathers? Pcv is supposed to help with oil leaks- cant hurt.

[daryl w66]

Just breathers. 1 on each valve cover

[blykins]

After 3-4 seal changes, I'd be looking at another source.   I'd at least pull the trans and bell off and see if there's a trail coming from a cam plug, gallery plug, etc.

[My427stang]

Leaky FE rear main troubleshooting

1 - Make sure no leaks from other places trying to fool you (intake, v/c, oil pan, galley plugs, cam plug, intake plate, or misshapen pan due to tall bolts or studs)
2 - Make sure pan, gaskets and windage tray does not block #5 main cap oil return (if yes, you are dead in the water until you fix)
3 - Make sure seal is in the right direction and high quality (I like Clevite/Mahle better than Felpro nowadays, but mostly due to side seals, not the seal itself)
4 - Whatever side seal method you use, do it right....LOL  I like side seals and nails, with RTV, fitted and installed AFTER the main cap is torqued, others use only silicone, both work if you do the job well, if you don't, neither works.  Could be said for anything, but lots of ways to do side seals wrong
5 - Make sure main alignment is good, to include the seal is centered and not crushed due to excessive cut (too late now really until rebuild)
6 - Some SCAT cranks delivered with bad oil deflectors, normally, I saw them hit the cap, none were too small (3 of them out of 4 over last 2 years), however, in theory, could create a pumping action as they were misshapen and wavy (This is a reach, but that part of a SCAT crank was crazy for a bit)

I really cannot think of anything else

[daryl w66]

Thanks for all the help. I will start by pulling out the trans. and bellhousing and check the back of engine for leaks. I would still hope to get some suggestions for an engine builder for my fe in Vancouver b.c. area if that's what I have to do in case the leak is indeed the rear main seal. Thanks again!

[SSdynosaur]

TomP posts here frequently, is from the Vancouver area and, likely, familiar with most area shops knowledgeable in FEs. He will probably join in as soon as he sees your request.

[daryl w66]

Thanks

[fairlaniac]

Leaky FE rear main troubleshooting

1 - Make sure no leaks from other places trying to fool you (intake, v/c, oil pan, galley plugs, cam plug, intake plate, or misshapen pan due to tall bolts or studs)
2 - Make sure pan, gaskets and windage tray does not block #5 main cap oil return (if yes, you are dead in the water until you fix)
3 - Make sure seal is in the right direction and high quality (I like Clevite/Mahle better than Felpro nowadays, but mostly due to side seals, not the seal itself)
4 - Whatever side seal method you use, do it right....LOL  I like side seals and nails, with RTV, fitted and installed AFTER the main cap is torqued, others use only silicone, both work if you do the job well, if you don't, neither works.  Could be said for anything, but lots of ways to do side seals wrong
5 - Make sure main alignment is good, to include the seal is centered and not crushed due to excessive cut (too late now really until rebuild)
6 - Some SCAT cranks delivered with bad oil deflectors, normally, I saw them hit the cap, none were too small (3 of them out of 4 over last 2 years), however, in theory, could create a pumping action as they were misshapen and wavy (This is a reach, but that part of a SCAT crank was crazy for a bit)

I really cannot think of anything else

Ross,
I've never read about #2.

"2 - Make sure pan, gaskets and windage tray does not block #5 main cap oil return (if yes, you are dead in the water until you fix)".

Any pictures of this issue? I have a windage tray and in the coming weeks plan to attempt to fix my well documented leak. I planned on changing the seal and side seals and hope luck was on my side. This might be something I overlooked and would make me more confident if I could find something wrong when I redo my seal.

Thanks,

[blykins]

Leaky FE rear main troubleshooting

1 - Make sure no leaks from other places trying to fool you (intake, v/c, oil pan, galley plugs, cam plug, intake plate, or misshapen pan due to tall bolts or studs)
2 - Make sure pan, gaskets and windage tray does not block #5 main cap oil return (if yes, you are dead in the water until you fix)
3 - Make sure seal is in the right direction and high quality (I like Clevite/Mahle better than Felpro nowadays, but mostly due to side seals, not the seal itself)
4 - Whatever side seal method you use, do it right....LOL  I like side seals and nails, with RTV, fitted and installed AFTER the main cap is torqued, others use only silicone, both work if you do the job well, if you don't, neither works.  Could be said for anything, but lots of ways to do side seals wrong
5 - Make sure main alignment is good, to include the seal is centered and not crushed due to excessive cut (too late now really until rebuild)
6 - Some SCAT cranks delivered with bad oil deflectors, normally, I saw them hit the cap, none were too small (3 of them out of 4 over last 2 years), however, in theory, could create a pumping action as they were misshapen and wavy (This is a reach, but that part of a SCAT crank was crazy for a bit)

I really cannot think of anything else

Ross,
I've never read about #2.

"2 - Make sure pan, gaskets and windage tray does not block #5 main cap oil return (if yes, you are dead in the water until you fix)".

Any pictures of this issue? I have a windage tray and in the coming weeks plan to attempt to fix my well documented leak. I planned on changing the seal and side seals and hope luck was on my side. This might be something I overlooked and would make me more confident if I could find something wrong when I redo my seal.

Thanks,

Felpro cork gaskets are cut out in the right spot, but some windage trays may block the oil drain in the #5 main cap.  If it's blocked and can't drain easily, it could potentially back oil up through the seal.

[My427stang]

This is a pirated picture trying to show how to clear the nuts when washers are used with bolts or studs are used, but it's good for a pic of #5



See the drain area and how it is covered?  Most pans are good now, but there were some in the past that covered that oil drain on #5, and what happens is you pressurize the seal from the rear main bearing flow, and no way it can hold oil

Second, almost all windage trays I use, all brands, I clean up in that area, because as you can see, even that one covers it slightly.  I have seen original FOMOCO stampings that covered it completely.  Even the one in the picture is worse than it looks because the passage in the cap lays back at an angle.  That one sure wouldn't pressurize, but it is sloppy to leave it.

As a side note, I generally have to clearance the front of the pan for a disptick too, other wise you have to wiggle and jiggle to get the dipstick to go down and not into the crank.  Both modifications are real easy

Like Brent said, the pan gasket is generally not the issue, but I lay them all down and make sure a clear path to drain oil from the rear main before I start sealing things up

[Yellow Truck]

Thanks for all the help. I will start by pulling out the trans. and bellhousing and check the back of engine for leaks. I would still hope to get some suggestions for an engine builder for my fe in Vancouver b.c. area if that's what I have to do in case the leak is indeed the rear main seal. Thanks again!

I'm over on the Island, and one of my neighbours Percy is basically Mr. Carburetor over here, supporting the local car community for years. He used to build circle track cars, but that scene is dead over here. Percy will build anything and has assembled some FEs, but he really is a SBF guy. He swears by Jim Richmond at Richmond Engines over in Surrey. Jim won't be an FE guy in the way some of the guys on this forum are, but he has a very sophisticated shop and if you went in with some things to check from the advisors on this forum I'm pretty sure he could sort it out.