2000 Explorer rear main seal leak

[parchment10124]

Hello my name is Anthony and I have a 2000 Explorer Eddie Bauer that have had an oil leak now for ever. I have replaced the rear main seal 3 times and it still leaked, each time with in about a month or 2 after replacement. Has anyone experienced this issue before and what did you find was the problem? Any feedback that you can offer would be really appreciated.

 

[Turdle]

The only thing I can think of would be a small burr on the crankshaft which might be tearing up the seal. Going over it with emery cloth might help.

Or-the rear main bearing has play--worn out. Excessive blow by might also cause crank case pressure build up. Have you replaced the PCV valve?

 

[mounty71]

Figured I'd post here instead of starting a new thread. Long story short, I replaced my rear main seal a couple of months ago, replaced the PCV valve at the time for good measure even though the original seemed fine to me. Less than 1000 miles later my rear main is leaking worse than the first time. In doing more research I came across other forums (mustang, crown vic,...other cars offered with 5.0s) where people mentioned the PCV screen needing replacement. I came back to this forum and searched around for any mention of that because I hadn't read about it the first time around, and found nothing which I was surprised by. It's also not listed as a part on Rock Auto, Autozone, etc. Today I tried to see if there was that screen in my engine and there isn't. So now I'm curious, is that part not used in Explorer 5.0s?

 

[Turdle]

Figured I'd post here instead of starting a new thread. Long story short, I replaced my rear main seal a couple of months ago, replaced the PCV valve at the time for good measure even though the original seemed fine to me. Less than 1000 miles later my rear main is leaking worse than the first time. In doing more research I came across other forums (mustang, crown vic,...other cars offered with 5.0s) where people mentioned the PCV screen needing replacement. I came back to this forum and searched around for any mention of that because I hadn't read about it the first time around, and found nothing which I was surprised by. It's also not listed as a part on Rock Auto, Autozone, etc. Today I tried to see if there was that screen in my engine and there isn't. So now I'm curious, is that part not used in Explorer 5.0s?

I have never seen a PCV screen. The only thing I can think of is the baffle area in the intake manifold for the pcv vacuum. But if there is good vacuum in the pcv hose I doubt it is clogged.

There is a baffle in the valve cover on the passenger side, this is where crank case vent air would enter.

Worn compression rings will allow blow-by, which is the most common cause for a blown main seal. Main bearing wear can also be a factor.

If it was me, I would replace it again,( easy for me to say huh?) using an emery cloth to polish the crankshaft surface a bit. You might replace the front transmission seal also, in fact are you sure the trans seal is not the leaker?

 

[mounty71]

This is the screen I'm referring to. If no one here has heard of it/seen it, and my truck hasn't had one all its life then I'm not worried about it. I was just curious.

My plan is to replace it again, this time using a crankshaft repair sleeve. I didn't use the repair sleeve before because I've read that it can stress the seal and cause leaks also and I felt that the crankshaft was in good shape, but maybe it wasn't. I did clean up the surface as best I could too.

It's definitely motor oil that's leaking. It would be trans fluid leaking if it were the trans seal, no? If this 2nd seal doesn't fix it, I might just go for some stop leak, which I'm nervous about using, but if there's a bigger internal problem in the motor like you're suggesting then a little stop leak in there should be the least of my worries.

 

[mounty71]

Just wanted to update this. I think my seal was fine, it looked to be in perfect condition still, although I still replaced it to be sure. The leak was most likely coming from me using thread locker on the flex plate bolts instead of thread sealer. I didn't realize the threaded holes in the crankshaft pass all the way through to the crankcase. That would explain why it was leaking so much worse than when the original seal was leaking. I pray that that was indeed the cause for the leak. No way in hell I'm taking this transmission out again until it needs a replacement.

 

[Turdle]

Just wanted to update this. I think my seal was fine, it looked to be in perfect condition still, although I still replaced it to be sure. The leak was most likely coming from me using thread locker on the flex plate bolts instead of thread sealer. I didn't realize the threaded holes in the crankshaft pass all the way through to the crankcase. That would explain why it was leaking so much worse than when the original seal was leaking. I pray that that was indeed the cause for the leak. No way in hell I'm taking this transmission out again until it needs a replacement.

Just popping in to ask for clarification.I just replaced a ( perfectly good) main seal and am wanting to button up. The only reason I relaced it is the engine is out of the truck.
After removing the flex plate from a stock engine here I saw nothing on the flex plate bolts. No sealer or thread locker. Are you sure these holes are through holes and not dead ended?

Edit. flywheel (flex plate) holes are indeed blind ended. I do not think oil should leak from them.

 

[masospaghetti]

Hello my name is Anthony and I have a 2000 Explorer Eddie Bauer that have had an oil leak now for ever. I have replaced the rear main seal 3 times and it still leaked, each time with in about a month or 2 after replacement. Has anyone experienced this issue before and what did you find was the problem? Any feedback that you can offer would be really appreciated.

Did your crank have a repair sleeve installed on it? I had issues with a repair sleeve installed backwards on mine and it tore up main seals in short order.

Also, are you using the regular nitrile-rubber seal, or the teflon seals? The rubber ones need to be lubricated before they are installed, the teflon ones must be installed dry.

Lastly, how are you installing them? If they go in crooked they may warp.

 

[mounty71]

According to this video the holes in the crankshaft are open-ended. This is the company I got my seal and repair sleeve/tool from. But at this point I'm at a loss because the damn thing's leaking again. I drove it home from the shop where I fixed it about 30 miles away, it was dry when I got home, and the truck hasn't moved since then and is leaking now. I'll just add some stop-leak like I should have from the beginning, and drive it till it won't drive anymore. I'm sorry to say that I don't think you should have touched the original seal if it wasn't leaking. There's a good chance you've created an endless problem for yourself.

https://www.youtube.com/watch?v=IZBI-0Vz9OY