The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support Kiggly Racing
Please Support STM Tuned

Timing Belt Oil Leak

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

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

Dsmturbo

Proven Member
56
8
Jan 20, 2015
SoCal, California
Hey guys I'm trying to track down the dreaded timing belt oil leak. A little background, it's a built 6 bolt into a 2g with only about 2500 miles on the motor. Originally I was slightly concerned about high oil pressure but I'm not sure if high oil pressure would be the culprit behind this leak or if it's just from a poor install?

I've researched a bit and I know some of the common oil leaks are from the cam shaft seals and crankshaft area. However those don't seem to be my problem as the oil leak seems to originate somewhere around the tensioner pulley and pours down, but I'm having a hard time figuring out exactly where it's coming from.

I've pulled off the timing covers to check for the leak and then cleaned everything up and used some UV dye to narrow down the issue as you can see in the pictures below.

I'm going to obviously be replacing the timing belt, tensioner/idler pulleys, auto tensioner, and water pump but I want to make sure the leak is fixed so all that work and money isn't for nothing. Could it be the tensioner pulley itself? Does the tensioner arm bolt intersect an oil gallery? Is there anything behind that that can be leaking? Any ideas on where/what is leaking please let me know! Thanks! Hopefully the pictures below help.

Cam seals/Head looks clean, no leaks
You must be logged in to view this image or video.
You must be logged in to view this image or video.
You must be logged in to view this image or video.
You must be logged in to view this image or video.
You must be logged in to view this image or video.


Oil pooling/leaking around tensioner pulley area
You must be logged in to view this image or video.
You must be logged in to view this image or video.
You must be logged in to view this image or video.
You must be logged in to view this image or video.
 
The 2 hydraulic tensioner bolts do come near oil passages in the front case. It is possible for oil to make its way up through those bolts.
 
@bobster22388 Are you talking about these two bolts on the auto tensioner?

You must be logged in to view this image or video.


I thought it could be from there originally but when I did the UV test it seemed to come from the tensioner pulley/tensioner arm area. Any idea if the right bolt on the tensioner arm intersects an oil passage?

You must be logged in to view this image or video.
You must be logged in to view this image or video.
You must be logged in to view this image or video.
You must be logged in to view this image or video.
 
@bobster22388 Are you talking about these two bolts on the auto tensioner?

You must be logged in to view this image or video.


I thought it could be from there originally but when I did the UV test it seemed to come from the tensioner pulley/tensioner arm area. Any idea if the right bolt on the tensioner arm intersects an oil passage?

You must be logged in to view this image or video.
You must be logged in to view this image or video.
You must be logged in to view this image or video.
You must be logged in to view this image or video.

It shouldn't come from the pivot part since that part actually bolts on separate to the block itself like the motor mount on that side. They really are a pain to nail down.
 
@Chumpaumpalumpa Definitely not driving it, starting it for about a minute and checking for leaks (which I know is also dangerous/not ideal but I gotta find this leak).

@2gmitsueclipse Read those and several other threads before posting, seems like the cam seals are a common trouble area for this sort of leak but cam seals look good. Leak seems to start around the tensioner pulley area. I guess I'm going to just have to remove everything and hope the problem presents itself. I just to waste money on a new timing belt job only to have the problem persist :/
 
Have you tried running the engine with the covers removed? Possibly also spinning the oil pump to build pressure without running the engine to find the source of the leak?
 
I had this same exact problem after replacing my Hydraulic tensioner. Turns out it was leaking from the two bolts that actually hold the tensioner in. Put some RTV on the ends and torque it down to spec.
 
i'd about put my money on the 2 tensioner bolts. those 2 go through the oil pump cover which has alot of pressure. after a balance shaft delete we left a bolt out that went to the pulley to the balance shaft belt. oil found its way through the gasket to leak out of the hole. it may not be the problem but its a possibility.
 
Is it possible that the leak is coming from just above the pulleys where the head mates to the block?

Perhaps headgasket issues or improperly torqued head bolts/studs? I'm just spit balling ideas so you can explore other options if the tensioner or pulley bolts aren't the culprit.

As far as spinning the oil pump, I believe you are correct. Just remove timing belt and spin it. This is done on new builds to prime the pump, so you shouldn't have any issues.
 
I highlly recomend you to change/check the pump sprocket seal

I had the same problem and was the O ring behind this nut
You must be logged in to view this image or video.
 

Attachments

  • images.jpg
    images.jpg
    6.1 KB · Views: 136
Last edited by a moderator:
that'll leak to. screw driver and a hammer will tap that out. take the gear off obviously. go to autozone or any parts stores, get a uv dye bottle for oil. run the engine for a while then at night go in with a black light. it'll show you where its at. or where the oil splashed
 
I used Grey Permatex on every bolts threads that go into the front just to avoid this as I had a persistant oil leak before my rebuild but now, its bone dry. I did it because it is just cheap to RTV all of them so you don't have this problem from a bolt, but if its a seal it will still give you problems of course.
 
Dont forget if the seal on the front balance shaft was changed it might not of sealed correctly. It can be a pain.

If you do remove that castle plug be real careful putting it back as it can snd will crack the case if you over do it! Everyones moto here is if its not leaking from it at all LEAVE IT ALONE!
 
Hey guys sorry it's been a while but I have a slight update. Took everything off and used my drill to spin the oil pump. Oil pump sprocket seal was leaking big time so I replaced that. Put everything back together and of course it was still leaking, not as bad but still leaking.

Took off the timing cover and added uv oil dye again and the leak has to be coming from around the tensioner arm area. Again it's not the cam seals, the head is perfectly dry. It appears to be coming from around the tensioner arm or slightly above it (looking back at my first post the oil is pooling right under the tensioner arm). I attached a picture regarding bolts that I believe could be leaking, mainly the tensioner pivot bolt, top tensioner arm bolt, or possibly the bolts from the motor mount?

Can anyone tell me if any of those bolts in this area intersect an oil passage? Thanks guys I really appreciate the help!

You must be logged in to view this image or video.
 
um. i do see something wrong with those tensioner pulleys...if im not mistaken.
there shouldnt be two with the manual tensioning holes.

past that, i bet the gasket for the oil pump housing is split on the top somewhere, and its pumping up and out to the pulley, getting slung all over the rest. just a thought.
 
Thanks for the input TameTalon, I should note I pulled that pic from a google search sorry, it's not my motor. It was easier to point out than my motor since it's in the car LOL

But good point about the oil pump housing gasket! Is the top of that gasket/housing right around the tensioner arm? That might explain why it just seems to be seeping out and I can't pinpoint the leaks location.
 
Oil leak on a fresh rebuild like that would indicate the front case gasket, or oil pump gasket as it is commonly called, was not installed correctly. They can be a real pain in the ass to replace and if they have never been removed before they rarely ever leak or need to be replaced

You have to be pretty exact when lining up the new gasket to the block and the pump, and you need to torque everything evenly as you install it to prevent any slips or potential tears.

I for reference I cut off the exposed corner thinking it was a pice of the old water pump gasket, but it is in the same region as your oil leak
 

Attachments

  • 2015-11-16%2001.06.07_zpsfyqjtqcq.jpg
    2015-11-16%2001.06.07_zpsfyqjtqcq.jpg
    78.3 KB · Views: 198
Last edited:
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top