Hey All I am need of some help. I haven't gotten My Montero more than a block since I've owned it and I really want to get it going. It all started when I bought it for $650 with a broken crank bolt. Long story short I ended up pulling the engine to replace the crank. Got it all back together and stuffed back into the vehicle everything buttoned up fired it up and she ran perfect. I warmed it up for 15-20 mins and drove it around the block, put it in park with a big grin on my face thinking of how proud my wife will be when I looked under the vehicle to check for leaks and watched a steady stream of oil dumping out of the bottom of the timing cover. That wiped the s*** eating grin right off my face.

Okay so after removing everything and getting down to the crank it is obvious that the front main seal is the leak point. I have replaced it now twice and I a keep muffing up the rubber outer edge of the seal on the oil pump case/mating surface. It's getting really frustrating, should I round the edge of the oil pump seal surface down just a bit to help the seal seat without tearing up the rubber? It's driving me crazy and i'm getting tired of ordering new seals and installing just to see them leak <img src="/forums/images/graemlins/scared.gif" alt="" />

94 SR Montero

When I did mine my mechanic uncle told me to rub a very thin coating of the ultra grey permatex rtv around the outer edges of the seal before putting it in. I guess the theory being that it helps it slide in smoothly and then once it dries it also helps seal any tiny imperfections in the metal and keeps it in place.

Also are you using mitsu oem seals? The rubber quality is usually superior to the aftermarket brands.

Short course on seal install.

Pack the seal cavity where the spring lives with grease. I like silicone, but axle grease is fine. This keeps the spring from popping out as you drive it. Also smear some on the seal friction lip.

If the seal bore has a sharp lip on the entry, knock it off, but don't scratch the bore in the process.

I use blue rtv on the seal perimeter so it slicks in and seals tight.

Use a piece of pipe just smaller than the seal bore but large enough not to impinge on the rubber of the seal to drive the seal square and evenly.

Use antiseize on the crank snout so the timing belt sprocket and balancer will come off easy next time. Trust me on this one...

If you've replaced it twice and still have the same problem, check the sealing surface on the crankshaft for scratches or other damage. If the seal doesn't have a smooth surface to seal against you'll be getting leaks there no matter how many new seals you install. There are repair sleeves available if you find that your crank has some sort of damage.

Beat me to it. Just that. ..

Tried this on the first seal but on instal the rubber on the outer edge of the seal peeled back as I installed the seal. That time I used a seal from rock Auto DNJ. Turns out it is the OEM seal cause the last seal I ordered was OEM and was exactly the same. Thanks for your reply.

Thanks for the info Fasteddy I think I may try to knock down the edge just a bit with some emery cloth to assit the seal and get it started. Also with try to add more RTV. I've got a good sized pipe fitting. I'm also wondering if the cold temps i'm working in are shrinking the bore hole just enough to cause all this. Maybe not I think the first time I replaced the seal was back in the fall in warmer temps. Nevre thought about pavking the seal with grease to keep the spring from popping off good call. As always your responses are incredibly insightful and helpful. I'm glad this forum exists.



The crank better not have any damage as it is a reman that a shelled out some $$ for plus the snout looks fine, every time I have installed the seal the outer edge rubber peels back just a bit. Having not done this before I wasnt sure if that was normal but now through trial and error and from others comments I know that that is not suppossed to happen and that's keeping the seal from sealing against the bore of the oil pump case. So i'm trying to figure out how to get the seal to slide in without ripping up the rubber outer edge.

Two more seals down the toilet! Looks like I've got some kind of issue with the seal bore. There is a pretty good ridge that keeps peeling back the rubber of the seal you can kind of make it out in the picture. Dont know how it happened or how the old seal managed to not leak.

[url=http://www.4x4wire.com/forums/post-images//1288376-sealbore2.JPG

Today I tried heating the oil pump case up with a heat gun, coated the outer seal surface with RTV, and tried to knock down the edge of the bore but still getting the same results on every seal. I may try coating the already peeled seal with RTV and putting it back in and let it set up. Only other thing I can think of is a new front oil case.

The last seals I put in, I used the RTV around the outside, like you, but I also used a Q-Tip with silicone spray on the end to carefully lay some of the liquid on the crankshaft snout. As I put the seal into place by hand, I twisted it clockwise to try to keep the inner lip from catching on any edges, too. Seems to have worked... Good luck, that has to be frustrating.

John B.

Yep super frustrating! What should be a simple thing is turning into a real pain. I'm going to try to just RTV it in there and see if it'll do.