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Discussion Starter · #1 ·
Alright, I was going to post this in the HELP! section, but I figured that since this has been a problem for the last 9 months its not too pressing of a problem.

My oil pump leaks from the oil pump shaft seal, where the gear for the timing belt goes, its leaking where the seal seats on the inside of the sprocket not where the shaft sticks out of the sprocket and a nut goes (the front of the gear) its not much of a leak but its still a leak that messes up everything, sometimes its been enough to get on the timing belt which is not good AT ALL. The oil pump/frontcase was almost new (few hundred miles, pretty sure it was an OEM mitsu one,I'll check I still have it) when I bought the car, it leaked when I got it, I replaced the oil pump seal and yanked the b-shafts, it still leaked, I replaced it with an oil pump/frontcase with a new gear from advanced auto with a beck/arnley one, it still leaks, I replaced the seal just now with a mitsu one, and I put the oil pump onto my new engine, and after about 20 miles or so now I notice its still leaking, my oil pressure is pretty high now with no b-shafts and no oil squirters (it clears 100psi on a cold start) and after its warmed up normal RPM driving its about 75 psi, but I dont think thats the problem because its been leaking for awhile. Is the advanced auto one a piece of junk or am I doing anything wrong? Any input would be much appreciated, I know what I am doing with anything under the hood on that car but I cannot figure this one out.

My last resort is going to be returning the advanced auto oil pump (life time warranty) and then returning the new one for cash and then ordering a mitsu one from Conicelli.

Is there anything that I could be doing wrong with the seal?

Thanks in advance to anyone who has any ideas.
 

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Discussion Starter · #2 ·
Well nobody has any ideas on this......so I plan on just getting another new oil pump, hopefully I can return the other one under warranty, but is the frontcase/oil pump that SBR sells a Mitsu one or some other brand? And does it matter?

http://slowboyracing.com/Engine/front cover/front_cover.html

That seems like a pretty good price.
Otherwise I'll order one from Conicelli, if I get one from a Mirage I wont have to put a freeze plug in for the front B-shaft. Does anyone know the part number or year that is?
 

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I think the Slowboy frontcase/oil pump is Topline brand, not oem, but you could email them to find out for sure.

When you eliminated the balance shafts, did you use a new short stub or cut the old balance shaft down? If you reused the old one, perhaps the surface of the shaft is damaged causing the leak. When you replace the seal, do you use some assembly lube or engine oil on it where it meets the shaft? Also, a little rtv around the outside of the seal doesn't hurt.
 

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Discussion Starter · #4 ·
redawdturbo said:
I think the Slowboy frontcase/oil pump is Topline brand, not oem, but you could email them to find out for sure.

When you eliminated the balance shafts, did you use a new short stub or cut the old balance shaft down? If you reused the old one, perhaps the surface of the shaft is damaged causing the leak. When you replace the seal, do you use some assembly lube or engine oil on it where it meets the shaft? Also, a little rtv around the outside of the seal doesn't hurt.
I originally cut the B-shaft, but I suspected that as being the problem and then bought the OEM stub shaft, still leaked.
I lubed the seal when I put it in, I tried it w/ and w/out RTV around the seal, its not leaking there, its leaking where the seal seats around the inside of the oil pump sprocket, not where the seal goes into the front case.
 

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Yeah i just realized the b-shaft shouldn't affect a leak there. You said you did replace the oil pump drive gear as well?
 

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Discussion Starter · #6 ·
redawdturbo said:
Yeah i just realized the b-shaft shouldn't affect a leak there. You said you did replace the oil pump drive gear as well?
Yes, I replaced the front case, which came with new oil pump, both gears, seals, and I've tried new (FelPro and OEM Mitsu) seals too. I dont know what else I can do, its not a terrible leak, but it still shouldnt leak at all.
 

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I can't picture the seal you are talking about, but have you replaced whatever shaft or gear it is that goes through the seal? I'm sure you have but if you have replaced the shaft/gear, seal, and oil pump then I don't see how it could still be leaking. Good luck though!
 

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Discussion Starter · #8 ·
I started by replacing the seal on the almost new frontcase/oil pump that came on my car, still leaked, I replaced the WHOLE thing with one from advanced auto, still leaked, replaced the seal with an OEM mitsu seal, still leaks thats where Im at now. Next step is to get another new frontcase/oil pump (everything) from Conicelli unless someone has any idea or suggestion that could even be a slight possiblility.

Anything???? Wild guesses welcome!:confused:
 

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When you removed the balance shafts I assume you went with a balance shaft eliminator kit, using the stubby shaft for the oil pump. I would check the clearance of this stubby shaft to the rear bushing on the oil pump housing. I think it seats into the rear of the housing, yea it does. If there is enough wear on the housing to allow the shaft to move side to side, then when it is under tension from the timing belt during normal operation it will run at and angle to the front seal. The ideal position for sealing is if the stubby shaft runs perpindicular to the sealing face, a slight lean from a worn housing will cause it to pull the seal to one side and leak.
This would also be the same for worn oil pump gears, if there is enough clearance to allow the stubby shaft to move side ways the seal will leak. The stubby shaft allows the timing belt to act on a smaller lever than the longer balance shaft and wear the rear oil pump housing slightly quicker. Basically you have the same amount of force on the oil pump sprocket acting on about a 2" inch lever than it would be over a 8" balance shaft with two journels for support, this will increase the force on the oil pump housing bush. The housing being aluminum and the shaft being hard steel, I think it pretty much the housing that wears first.
To technical I am sorry, hope this helps, another question why did you remove the oil squirters? The ones under the pistons, these provide valueable lubrication for the pistons and cooling. The oil pressure you quoted is also way to high.
 

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Discussion Starter · #10 ·
The oil pump is tight, theres no play in the stub shaft, or in the shaft driven by the timing belt. Theres basically zero wear in the front case because it only has like 40 feet on it (ok maybe 400 miles) and I just had it apart. I think either my car or myself is cursed.

I didnt use oil squirters because I built a 6 bolt NT block. The squirters are not needed, especially with forged pistons. I looked into this extensively.

As for the oil pressure, it maybe high, but thats not the cause of the oil leak because I had this same leak when I had this oil pump on my other engine.

Im just gonna replace the POS again, I dont know what else I can do.
 

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Does the oil pump gear shaft press against the seal or does the pulley that the timing belt drives press against the leaky seal? IF its the pulley that presses into that seal (I wish I could remember, I removed my balance shafts over the summer), I would order a new pulley. I bet it's worn enough that even a new seal will leak. If it's the gear shaft that presses into the seal, try pulling the seal out and using grey RTV on the outside edge of the seal, or replacing that gear shaft (if you havn't already). Maybe its leaking around the outer edge because of the higher oil pressure? I can't believe that two oil pump housings were bad causing the seal to leak. Good luck though!
 

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Discussion Starter · #13 ·
aaron31182 said:
Does the oil pump gear shaft press against the seal or does the pulley that the timing belt drives press against the leaky seal? IF its the pulley that presses into that seal (I wish I could remember, I removed my balance shafts over the summer), I would order a new pulley. I bet it's worn enough that even a new seal will leak. If it's the gear shaft that presses into the seal, try pulling the seal out and using grey RTV on the outside edge of the seal, or replacing that gear shaft (if you havn't already). Maybe its leaking around the outer edge because of the higher oil pressure? I can't believe that two oil pump housings were bad causing the seal to leak. Good luck though!
The sprocket that is driven by the timing belt presses against the seal, and thats where its leaking between. The advanced auto Beck Arnley oil pump came with a new sprocket.

At this time I am not suspecting high oil pressure to be causing it to leak, because it leaked from the same place on my stock 6 bolt (with b-shafts and squirters, and then still after I yanked the shafts) and now on my new engine it still leaks, when I put the frontcase/oil pump on my new engine I put in a new Mitsu oil pump seal. I'll take a couple pics of the oil pump that was in my car when I got it, after looking at it Im not sure if its a Mitsu or some aftermarket because I cannot find any Mitsu part numbers on it, so now Im thinking its probably some el-cheap-o thing. Looks like the next step is going to be trying a brand new one (the whole thing) from Conicelli.

Also what is normal oil pressure for a stock engine (with b-shafts and squirters?

Without b-shafts and squirters my oil pressure is:
cold start idle at 2k 100psi
idle warmed up 10-15psi
driving at 2k rpm 50 psi
driving 75mph 3400rpm 75 psi
 

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Its possible that pulley might not be within spec but that probably isn't the case. You could try this: get a new seal from mitsubishi, take the spring out of the seal you have in there now, add it to the new seal so that it has two springs, and use grey RTV on the outside. That way you'll have more spring pressure on the seal and the RTV to seal up the outside. I've heard about people using two springs on seals that wont leak but have never done it. It may work. It would be cheaper than a whole new oil pump.
 

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Discussion Starter · #15 ·
aaron31182 said:
Its possible that pulley might not be within spec but that probably isn't the case. You could try this: get a new seal from mitsubishi, take the spring out of the seal you have in there now, add it to the new seal so that it has two springs, and use grey RTV on the outside. That way you'll have more spring pressure on the seal and the RTV to seal up the outside. I've heard about people using two springs on seals that wont leak but have never done it. It may work. It would be cheaper than a whole new oil pump.
Never thought of that before, but its definitely easier and a ton cheaper than replacing the whole thing (again) and since its only leaking a little it might just be enough extra pressure on the seal to stop the leak. I'll order a seal and take off the timing belt cover and belt and get the seal out of there with out messin up the spring and then post back with the results in a few days.
Thanks Aaron.
 

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No problem, I hope it works. If you want to get even more pressure you may be able to cut some of the spring off to make it smaller, if that makes sense. That would increase the pressure even more on the seal, but you would have to look at the spring on there and see how hard that would be to seperate then put back together after cutting it.
 

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Discussion Starter · #17 ·
I found an extra oil seal laying around thats alittle smaller than the oil pump seal to use the spring out of, otherwise I took apart the spring of an old oil pump seal and it wouldnt be too hard to trim it and then put it back together, it just screws together (make sure you do not cut the tapered end).

Along with a slightly tighter spring, I also thought about drilling out the oil return hole behind the seal, the one that just drains back to the pan, the shaft and seal are oiled through the shaft and then drain back to the pan right through a small hole behind the seal. The purpose of that would be to make sure that Im not building up pressure behind the seal causing the leak, I compared the oil pump on my car to an old junk Mitsu one that I got for free and the return hole is slightly (1/64 maybe) larger on the mitsu pump compared to the cheap-o on my car.

Any thoughts on this, does it make sense or is it crazy?
 

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have you been putting in the seal backwards?? you said wild guesses welcome :dunno:
allthough i cant remember which way it goes... but im sure someone could chime in if you think thats what it is.... :dunno:

the other thing would be a somehow warped sprocket??? causing the shaft to turn all messed up....
 

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Discussion Starter · #19 ·
Im sure Im putting the seals in the right way, my front and rear mains havent leaked, and this doesnt leak....much...but it does and I WILL FIX IT or else, theres gotta be a way to do it.

I dont think that the sprocket is warped, because Ive had the engine running with the timing belt cover off (lower) and there is not the slightest amount of wobble to it, also Im on my second sprocket (came new with the whole assembly) I had a couple non-DSM mech's look at it to see if they could figure anything out, nothing more than hmmm...yeah maybe a slightly smaller spring in the seal would help, so thats what Im going to try when I get another new one from Conicelli on Wednesday.

I dont think high oil pressure is causing this but how much would 5w30 or 5w20 lower my oil pressure? And is that thin of oil ok to use? (Im gonna search right now, but if ya know, let me know)
 

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A couple more long shots here. Was that drain hole clogged with RTV when you put the oil pan back on? Or maybe the oil pan covers the drain hole? IMHO a bigger drain hole couldn't hurt.

Maybe the leak is really coming from the plug cap just above the b- shaft pulley? There is supposed to be an o-ring under it to seal.
 
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