3fe Oil Leak Mystery (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Jan 29, 2003
Threads
98
Messages
2,636
Location
Peyton, CO
Got a motor oil leak coming from the lower rear engine area. Have replaced oil pan gasket, valve cover gasket, and have had a shop replace the rear main seal during a transmission rebuild. Still have the leak. I've verified its not the side inspection cover. I've cleaned the entire engine and verified that its still coming from the rear engine area.

I've looked at the SOR catalog and I don't see any other gaskets or seals listed for that area of the block or head.

Where else can oil be leaking from on the back side of a 3fe?
 
Last edited:
On the head between and above the #5 & 6 sparkplugs is a small press-in plug that leads to an oil passage. These sometimes loosen and leak or blow out which can cause rapid oil loss inwhich case you'll may have to have the engine rebuilt. Check to make sure the leak is not here. If it is you can replace it with another plug, or better yet tap it so that a plug can be screwed in.
 
Steve-O said:
Could be one of the freeze plugs.... More likely to be a seal, but if both the rear main seal and pan gasket were replaced (correctly) they shouldnt be leaking. When that shop replaced the main seal, did they mention if they thought the leak was coming from there or not?

The shop had to go back in (2nd time) after tranny was rebuilt to remove/replace torque converter because it was out of balance causing vibration. When they did this, I asked them to check the real main seal again after they had replaced it the first time since it still had a leak somewhere back there. They said they replaced it again and also said it was not leaking so their first replacement was fine too.

They said they thought the leak was coming from behind the plate that goes between the tranny and block. They would not remove it to try to locate the source. This was a transmission shop and they didn't want to get that far into fixing an engine oil leak.
 
Godwin said:
On the head between and above the #5 & 6 sparkplugs is a small press-in plug that leads to an oil passage. These sometimes loosen and leak or blow out which can cause rapid oil loss inwhich case you'll may have to have the engine rebuilt. Check to make sure the leak is not here. If it is you can replace it with another plug, or better yet tap it so that a plug can be screwed in.

I did know about the famous plug. I've looked for it. Never found it. There does not appear to be any oil in that area of the head. I think this leak is from somewhere else but I'll look at that one more time to be sure.
 
*Possibly* leaking from the plug in the back of the camshaft bore. This is on the back of the block, behind the motor plate (on a 3FE/auto combination).

Mark...
 
Mark W said:
*Possibly* leaking from the plug in the back of the camshaft bore. This is on the back of the block, behind the motor plate (on a 3FE/auto combination).

Mark...

Mark, I seem to recall you have a low opinion of stop leaks and other additive "snake oils". In this case, do you think it's worth a try?
 
miker said:
Mark, I seem to recall you have a low opinion of stop leaks and other additive "snake oils". In this case, do you think it's worth a try?


Believe it or not "seal conditioner" is the one miracle in a can that I am willing to try. Generally it softens and swells old dried out seals. It actually works a lot of times. Not the best answer, but sometimes if allows you to delay a teardown.

But if you have leaks due to any other cause besides old stiff rubber seals, then it doesn't help much. It doesn't fill gaps or anything like that.

Mark...
 
Just puxhased FJ62 1989

Need help,? My first ? is the the rig has rear main oil leak?
How hard is that to fix and how expensive?
I purchcased it for $1075 id that a good deal?
Plus shipping $450.00 to Miami,Fl
Does any know a good shop in miami:rolleyes:
Thanks
Zach
 
X2 on the camshaft "freeze plug" at the back of the engine as a likely culprit.

unfortunately not an easy fix. if you are going to pull the tranny and the plate at the back of the engine to verify, i would suggest adding some fluoro dye to your oil and drive around a bit. the dye will glow under a black light and it will be easy to pinpoint the leak.

i don't know that those "stop leak" products will work if a freeze plug is leaking; i was under the impression that they worked by swelling up rubber seals. worth a shot though i suppose.

other things you can try to minimize the leak. if you're running synthetic oil switch to dyno oil; synthetic oil will leak out of places that regular oil won't. you could also try using a thicker oil, 20W50 if your current climate will allow it.

or you could just live with the oil leak and pretend you're driving a Land Rover. ;)
 

Users who are viewing this thread

Back
Top Bottom