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Oil Pump Shaft Seal Leak

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SlickPyro

10+ Year Contributor
226
6
Jun 5, 2008
South Euclid, Ohio
Alright here is what is going on and I assure everyone I have read up plenty on this. A few weeks ago I tore down the front of my engine to find where I had an oil leak. I found out that the cam seals, balance shaft belt pulley hole bolt, crank seal, and all other things were dry as a bone. I pulled to oil pump sprocket off and saw oil on the back of the sprocket and coming out of the seal. Now this engine I have only has like 2,000 miles. A stock rebuild with ARP hardware. I'm on a budget so when I rebuilt the engine I bought a topline oil pump and installed a mitsu oem bsek. So I replaced the leaky seal with a new oem seal and put the timing belt back on and everything. After a 250 mile drive from cleveland to columbus in the past week I lost 1/4 of a quart of oil on the way down. I filled it up before I came home but haven't checked to see how much I lost on the way back, I was going to check tomorrow before going to the shootout. Since replacing the seal didn't fix the leak what is the deal here? I read a few things saying if the oil pump sprocket has side to side movement then its F'd and replace it. I don't know if it does or not.

What I am wondering is can I buy a used oem front case and then buy new drive and driven gears for the oil pump and then replace it on my dsm since I have a topline pump that may or may not be causing the problem. Just looking for a little insight from some fellow dsmers. I thought it might be the tension of the belt pulling on the sprocket causing it to wobble in its bore causing the leak. The tension of the belt is set to where after you turn the engine over and wait 15 mins that you can put the pin in and pull it out of the tensioner.

Also I installed an AEM oil pressure gauge that is tapped right into where the stock sender was at, at the same time I was working on the seal and timing belt and I have good oil pressure. 11psi when hot at idle (perfect according to the factory service manual) and ~60psi IIRC when cruising on the highway going 70mph.

Just looking for a little help before I jack up my oil pump and in turn mess up the engine I built and have only put 2,000 miles on. I want to use this engine for a long time and this is the only thing wrong with it. I don't have the time or money to build another now and I really enjoy my dsm and I don't want to end up parting it out like so many others. Any insight would be very appreciated. Thank you.
 
Wonder if there is a minute shaft diameter difference, since you went 3rd party for a pump, where no seal will work to stop the leak.

Could also be a bearing issue ...

Or, you put in the seal without lubing first the shaft, or inner part of the seal with grease to sorta "prime" the seal and it lightly wore the inner section of the seal due to the dry shaft?

Some thoughts... good luck - DSM
 
What kind of bearing issue are you speaking of? The bearing inside the pump or engine bearings? I don't think not greasing the seal is the issue because the seal is supposed to be installed dry. I think I am going to pull the timing cover off again and see if the oil pump sprocket wiggles side to side at all. If so, new oil pump time. Just gotta save up to get an oem pump and seals. I'm happy I made it to the shootout and back. Just don't want to do much more driving and destroy the oil pump and the engine.

Sent from my Eris using Tapatalk
 
Did you ever fix this problem I just rebuilt my motor and installed and just got it running past few days now and fount that my oil shaft is leaking I used oem pump and all but have topline seals in it and kind wondering if I am having the same issue as you
 
i think i have the same problem ..its squirting oil like crazy!! can it be the seal?
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Good chance I just ordered a new seal from the dealer the topline one I had almost fell out of place when I assymbled it so I used a light coat of silicone to hold it their and I think it's not enough so hopfully oem will do the trick if your trying to find the leak take the timming cover loose and the balancer off spray shop solvent to dry and clean everything off real good start car just long enough to create good oil pressure then shut off and take a look if it looks wet with oil right around the oil pump you got the same problem as me and I'm 99% sure it's the shaft seal leaking even though it's brand new topline was kinda sketchy when installed
 
The oem seal fits loose in the oem pumps IMHO. I've done a little ultra grey fillet on them to keep them in. You could do a little fillet of JB weld.

Keep in mind guys that the seal seals on the sprocket, not the shaft. Make sure the sprocket is in decent shape, and the seal fits on it well. I like to use a little red loctite on the sprocket and shaft to seal it up a bit. I also put a little on the threads and the back of the nut to help seal every thing up.

Generally though if it leaks, it's cause the pump is junk. If you can fee any play in the sprocket, it's probably junk.
 
I am aware the seal is on the pulley and I had 3 differant pumps I tried and the only one that spun freely when assymbled was the original with straight cut gears so that's what I used the seal was just funky to me and I'm praying that's the problem I don't wanna take the ft case off again....
 
Just an update replaced the topline seal woth oem and tested fit of topline to oem in my opinion.. top line has found its self on my list of garbage seals... it not only basicly fell onto and off the seal point on the sprocket.. it ripe almost half way around the center.. I re read this thread just now and realized the OP used a topline pump gears. I prey they used better quality on that part I also checked for slop and side to side play my oem pump had some play but I'm a form believer as it needs some for oil theirs a small oil return hole right behind the seal for oil build up to drain to pan goes straight down checked it with an old ft case of mine. Best of luck to OP and don't wast a new rebuild on a bad pump of you can't get it to stop leaking get a new pump.. of you need as you said you on a budget I have 3 other used oem pump gears That had no problems that I know of they are heli. Cut gears not straight. If you need one ild gladly send you one free of charge just cover shipping. Good luck
 
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