Front Crank Seal - Any tips?
 

I put in a new Mazda-brand front main seal with the FM tool on my new-to-me engine prior to dropping it in. It leaks.

I got the timing belt covers back off and verified it's this seal. When I installed last time, I removed the old seal without any nicks, and reinstalled using the FM tool after putting some fresh oil on the new seal to help it slide into place.

What did I do wrong? The housing isn't nicked, the seal is OEM, so I'm not sure what happened. The RMS also leaks about the same amount, and I already had my mechanic do that one again, and it also still leaks.

Fortunately, the RMS is his problem, which makes me happy because repeated trans removals would make me an unhappy camper, but it's still relevant to my problem.

Anything I can do? Is my crank damaged? I'm not sure what I could be screwing up here. Is there some kind of sealant I could try on it?

Try finding a thinish washer and putting it on the crank bolt before using the FM seal installer. This will push the seal in less, and hopefully on a part of the crank that isn't grooved.

This is assuming there's a small groove in the crank and that's why it's leaking.

You should also be installing it with a small amount of oil on the inside, and a little RTV on the outside never hurts, although it generally doesn't leak there.

I seem to recall the mechanic might have said the RMS was leaking on the block side, not the crank side. I haven't pulled the timing belt pulley for the front yet, so I'll find out soon, but hopefully it's an outside leak RTV can fix.

I'll definitely give it a shot anyway, and the washer trick as well. Thanks!

I think I'm saying that wrong.

The washer needs to be on the inside of the tool, not on the crank bolt.

Right, crank then washer then tool then bolt, so it doesn't push the seal quite as far. Makes sense.

I won't get a chance to try it until I can get a new crank seal in in a couple of days.

Make sure you check 360* with a dental mirror for any gouges or grooves.

I had a deep outer surface gouge from the previous mechanic sliding in a screw driver to pop out the cam seal. I used emery cloth to sand down the lifted material and ultra-gray to help seal it. As of yet, it hasn't leaked a drop.

That's a good idea, I'll grab a mirror on my way home today. Couldn't get the timing belt cog off last night, it was being a dick.

Worthwhile to consider a common cause too. Do you have excessive crankcase pressure? PCV system working like it should?

Yeah, I did ask about that awhile ago. I already replaced the PCV valve to try to eliminate a stuck valve as an issue, and it didn't help. (I realize they typically fail open anyway.)

Is there anything else I can do to try to diagnose other possible causes? I don't know how I'd determine if the crank case pressure is too high.

I also did make sure the intake vent on the right side of the valve cover is clear, I can blow through it albeit it takes a little bit of force - I assume that's because it's like a foot and a half long and like 1/2" in diameter. Also had no oil in it.

I may also check the crank end play while the belts are off, I have a dial indicator in my shop already. It looks like excessive end play could cause both crank seals to leak?

That's a possibility. Friend of mine had a recent rebuild that ate itself because of a thrust bearing failure. He also did an oil analysis which clearly showed bearing wear. Another indicator he had was oil that turned black quickly due to blowby.

Ouch, that would be a bummer on a fresh rebuild. Hopefully in my case I just goofed up the seal or didn't see a nick or something... I got the timing belt cog off last night though and it appeared as though the seal could have pushed out a bit, which has me concerned.

The TSB for end play though has preconditions about noises, etc, and my engine runs buttery smooth, so hopefully that's not it.

I think it's .004"-.006", but above .008" on a new engine and you should be looking at tearing it back down.

Thanks. The engine is new to me, I dropped in a used engine but replaced the seals, TB, etc.

So I got some pictures of the crank. I think I way jumped the gun with the end play idea. Looks to me like the crank is scored and has some crap on it, I should have looked at it harder when I initially replaced the seal.

It almost looks like a press fitting on the end of the crank, with the oil coming from under the two slots on the bottom and top - is that how that normally is?

Anyway, any thoughts on whether I should get a speedisleeve or something, or just clean it and put on a new seal? I got the best pictures I could, hopefully they help.

Either way, thanks for all the help guys.

Bump. Any input on whether I need to do a sleeve? I don't know how to tell

If it catches a nail it'll most likely leak or chew up the sleeve, or both. There's no speedisleeve for these cranks.

Ok, got it, thanks. Timken and national have some listed on rockauto, do those not work?

FWIW in case anyone reads this later, no sleeve was required. I did derp the front crank seal up, apparently - crank just needed a little 800 grit, new seal, and some RTV on the block probably didn't hurt either.

Thanks for the help!