Jump to content
Ultimate Subaru Message Board

Leak behind oil pump wall help


Recommended Posts

Hi everyone, I currently have an oil leak in my 1996 subaru legacy 2.5 and, according to a mechanic, the leak is not coming from any seals, it is coming from behind the oil pump wall? I think "Oil Pump wall" is the wording he used. As pepboys doesn't get to deeply involved in engine work, the mechanic said I had to take it to someone who can fix the problem...he does not know exactly what is leaking, only that it is behind the oil pump wall.... also, last year I had my timing belt, cam seal and water pump replaced....

 

I was wondering if anyone has any idea what is leaking, how much work it will require to get in and fix it, and whether anyone would recommend me taking it to a dealer or engine shop...not sure which would be a little easier on my wallet and be able to fix the problem.....if anyone could provide some insight, I would greatly appreciate it. Thank you in advance for any help I get.....

Link to comment
Share on other sites

I'm no expert but it sounds like a classic case of the oil pump's back plate loosening. Search the board--there's been a fair amount of discussion of this.

 

Whoever did your timing belt last year should have checked the oil pump sealing (new o-ring and "loktiting" the screws) because--guess what--you gotta' remove the timing belt to get to it! Sorry. Good luck.

Link to comment
Share on other sites

I'm no expert but it sounds like a classic case of the oil pump's back plate loosening. Search the board--there's been a fair amount of discussion of this.

 

Whoever did your timing belt last year should have checked the oil pump sealing (new o-ring and "loktiting" the screws) because--guess what--you gotta' remove the timing belt to get to it! Sorry. Good luck.

 

 

Thanks for your help olnick, it's always appreciated.....do you or anyone know how you would fix the oil pumps back plate if it is loose and parts I should buy...new oil pump?....and does anyone else have any different opinion as to what the problem is....

 

I've looked through the haynes repair book as well as various posts on this site and it seems that removing the timing belt is more of a huge, time consuming pain rather than something which requires a lot of technical know-how....does anyone have any insight on how much technical know-how is required to do this and whether any special tools are required....thanks alot everyone.

Link to comment
Share on other sites

There are three places where the oil pump could be leaking.

a. The o-ring between the low and high pressure sides

b. The sealant which attaches the pump to the block

c. The crank seal

 

 

The latter two would cause a visible leak. Since you have the Haynes manual, if you are mechanically inclined you should be OK. If disassembling this mess make certain to inspect/replace everything, though it seems like you had most everything except the oil pump done last time. Timing belts, cam seals, inspect idler pulley, acc. belts, water pump, thermostat, and of course the oil pump (o-ring, sealant, and tighten/loc-tite the screws inside)... If I am missing something someone can chime in I am sure.

 

-Heikki

Link to comment
Share on other sites

There are three places where the oil pump could be leaking.

a. The o-ring between the low and high pressure sides

 

b. The sealant which attaches the pump to the block

c. The crank seal

 

 

 

The latter two would cause a visible leak. Since you have the Haynes manual, if you are mechanically inclined you should be OK. If disassembling this mess make certain to inspect/replace everything, though it seems like you had most everything except the oil pump done last time. Timing belts, cam seals, inspect idler pulley, acc. belts, water pump, thermostat, and of course the oil pump (o-ring, sealant, and tighten/loc-tite the screws inside)... If I am missing something someone can chime in I am sure.

 

 

-Heikki

 

thank you HKlaine, a couple more questions...I don't mean to be a pest, I just want to do this all right......if the water pump, crank seal, and timing belt were replaced last year...would these need to be replaced again due to the oil leak...also, the mechanic who looked at my car said it wasn't the crank seal or anything...that the leak was coming from "behind the oil pump wall". I'm not sure what that means, but I am hoping I can fix this myself.....Maybe he didn't remove the oil pump and this is what that means....not sure.....any additional help would be great....thank you all

Link to comment
Share on other sites

I don't see any reason to replace the water pump. I generally replace the water pump on every other timing belt (120k miles).

 

I would personally replace the crank seal since you will be removing the oil pump.

 

If the timing belt isn't due, shouldn't be a problem to reuse it as long as it is in good condition and DOES NOT HAVE OIL ON IT from the leak.

 

I am not sure what the mechanic means by behind the pump wall, but would assume this means the sealant between the pump and the block. I used Permatex Ultra-Gray for this and it worked great, no leaks after 30k miles. Make sure to check the screws inside the pump. If they are loose clean the threads thoroughly and apply some loc-tite blue before replacing them. I found three loose in mine. And of course replace the small o-ring behind the pump as stated before.

 

-Heikki

Link to comment
Share on other sites

Just to add, here's pics from my timing belt job.

 

http://www.main.experiencetherave.com:8080/subaru/images/timingbelt

 

That should give you an idea of what needs to be removed. Also, if you have a visible leak, it's probably the sealent between the pump and block. The ultra grey silicone is the correct silicone to use.

 

 

Thank's to both Hklaine and Legacy 777 for all of the advice you have given...after some careful deliberation I have decided to man-up and do the job myself. I figure if pepboys already removed all of the belts etc and got to the oil pump, all the necessary bolts and stuff should not be frozen and i should be able to remove them...worst case senario is I can't do it all and get the car towed to a place and I won't have to pay all the labor....:)

 

If anyone has any idea how long this should take for a newbie so I can plan out a time to do it...I would appreciate it....thank you all...I love this site

Link to comment
Share on other sites

  • 3 years later...

i thought the oil pumps on EJ's are supposed to be sealed with anaerobic sealer. i've read "debates" in other threads where folks have suggested there could be problems with dried up chunks of silicone getting into the oiling system. fel-pro has a crank seal set that comes with the crank seal, oil pump o-ring, and an oil pump gasket - i toss the gasket and use anaerobic sealer.

 

also, if you're going to replace cam seals get the two o-rings, not critical but a good "while you're there."

Link to comment
Share on other sites

  • 2 months later...

Sometimes I use just a little of that gasket adhesive stuff to hold the o-ring in the block recess so it doesn't fall out. The first time I did it, the o-ring fell out of the recess but I pulled the oil pump back off to double check something and noticed it phew!.

 

oilpumporing1.jpg

o-ring part # varies sometimes for different years

oilpumporing2.jpgoilpumpscrews1.jpg

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...