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Dealing With Oil Leaks

  • Thread starter Thread starter Mustang936590
  • Start date Start date Jun 22, 2017

Mustang936590

Member
Jun 22, 2017
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Jun 22, 2017
#1
  • Jun 22, 2017
  • #1
Two months ago I bought a 90 LX 5.0. In February the previous owner had a new T5 and clutch installed and while that work was done the rear main seal and oil pan and gasket were replaced. Problem is it still leaks a little oil. I've had the car on ramps and inspected the area and I'm 99% sure it's the oil pan gasket right under the RMS (I can see the oil slowly start dripping out and running down the front side of the plate between the pan and bell housing), which from reading about is fairly common. I've been monitoring the leak by placing cardboard under the car after I drive it and in my case I'd say it leaks 3-4 drops in the 1-3 days after driving. If I wipe the area clean then drive it there are no drops for over a day.

So my question is how much of an issue is this leak? I understand a 27 year old car won't be perfect but seeing as this work was just done should I even bother taking it to a shop to try to get the leak stopped. Just want to see what some other guys would do in my situation.
 

Real time recon

Mustang Master
Aug 21, 2016
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Jun 22, 2017
#2
  • Jun 22, 2017
  • #2
I have the same 90 Eng. And the same Exact oil leak as you described.I wouldn't worry about it too much.Just keep a close eye on it,as you have been doing.
 

Dan02gt

mazing how much gas smell came from that tiny hole
20+ Year Stangneter
Mar 2, 2003
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Jun 22, 2017
#3
  • Jun 22, 2017
  • #3
Oil leaks drive me nuts. It could be the oil pan gasket, but there is a better chance that it's the RMS. I had mine changed with I did my clutch and the new RMS leaked worse than the old one. I ended up having a Felpro Teflon RMS installed and that solved the problem.
 

Mustang936590

Member
Jun 22, 2017
35
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Jun 22, 2017
#4
  • Jun 22, 2017
  • #4
Thanks for the replies. That is really why this leak is driving me nutty because I do worry if it is the RMS the clutch will end up going so do I take it somewhere only for the leak to come back in a few months....but on the other hand if it's not the RMS I can deal with leaving it be for now and not spending the money to get the oil pan gasket replaced and sealed better.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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Jun 22, 2017
#5
  • Jun 22, 2017
  • #5
Mustang936590 said:
Thanks for the replies. That is really why this leak is driving me nutty because I do worry if it is the RMS the clutch will end up going so do I take it somewhere only for the leak to come back in a few months....but on the other hand if it's not the RMS I can deal with leaving it be for now and not spending the money to get the oil pan gasket replaced and sealed better.
Click to expand...

The flywheel is still there to act as a shield. If the RMS is leaking a tiny bit, it will just drip down the back of the block in between the flywheel and block and out of the bottom

If it was a massive leak, I could see it slinging around, but a few drips here and there, I wouldn't worry about it tooooo much, although I'd want to address it someday.
 

Mustang936590

Member
Jun 22, 2017
35
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Jun 23, 2017
#6
  • Jun 23, 2017
  • #6
Mustang5L5 said:
The flywheel is still there to act as a shield. If the RMS is leaking a tiny bit, it will just drip down the back of the block in between the flywheel and block and out of the bottom

If it was a massive leak, I could see it slinging around, but a few drips here and there, I wouldn't worry about it tooooo much, although I'd want to address it someday.
Click to expand...

Ok that's good to know. My other question I forgot to ask is, will the RMS or pan gasket leak when the car is parked? I last drove it two days ago and it drips about 1 drop every 12-18 hours so is what I'm seeing now just the residual oil that leaked when it was driven or do those areas leak oil even when the engine isn't running?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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Jun 23, 2017
#7
  • Jun 23, 2017
  • #7
Oil level is below the crank, so leaks are usually a result of the oil sloshing around while running, and then when parked, gravity pulls down any external oil. So the RMS leak is just whatever has oozed out while driving slowly draining down over time.

I have a slight RMS leak. 1-2 drops after parking. I just slide a small oil pan under the area when I park in garage. Keeps floor clean
 

BlakeusMaximus

Still got to try a little lube on my speedo head
5 Year Member
Jul 12, 2017
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Jul 12, 2017
#8
  • Jul 12, 2017
  • #8
I've got an 88gt and same thing. I bought the car, installed new clutch, rear main seal. Seal drips a little bit. I'm glad I saw this post cuz I had the same question.
 
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