Blankety blank Rear Main Oil Seal

Well, I was high with expectation, but ---.

History -- I have changed the rear main seal all by myself 3 times. Once, felt. Next, found out that the crank doesn't have the spiral groove, so went with the pricey rubber. Munched it up pretty good trying to install, but mashed it in there the best I could, considering the cost, and called it a day. And, it leaked. Then, split her AGAIN, and went with felt again. Leaked.

So, during the engine rebuild, I instructed the shop foreman to be very understanding of my dilema, and MANY times discussed the seal and how it was about 60% of my concern. He knew very well of my paranoia. Used the rubber again. He said it was difficult to install (paranoia rising)>

Well, I started the 400D first time today, it runs great, starts great on gas, and warmed her up 2 hours. Had the usual diesel fuel leaks, hydraulic leaks, water leaks, but fixed them all. Looked under the tractor, and everything is fine, BUT that +**+ seal is dripping about a drop every 10 minutes.

I'll tell you what -- I never intend to split this nightmare again (gas and diesel pipes, control rods, steering, wiring, hard to access frame to bell housing bolts, on and on). Leaky away buddy.

Does anyone feel sorry for me?

Yes, I'm telling the shop. Maybe they will send someone out to split the stinker for me, and try again. There goes the great paint though.

They sure area a pain to split. I don't feel sorry for you when you tried the felt seal twice. That was just stupid. You know darn well they won't work at all if they don't have the spiral groove.

Did you check the crankshaft to make sure it was straight? d282 was telling me how these cranks will go out of straight if you let the tractors idle too low for too long. I would guess the machine shop checked for that.

Did you check to make sure the seal retainer was flat/straight? My MD retainer was warped like crazy, but a 400 retainer is the upgrade to an MD retainer. The later tractors were cast iron where the old ones were white metal.

In the end, I am pretty sure mine still leaks a little even after I redid it last winter. I haven't investigated much, but I did see a drip or two at the bottom of the bell housing after plowing for a few hours. Mine is felt with a sprial and a 450 seal retainer.

Edit - M Diesel had mentioned to make sure the breather is clear. This will cause a pressurized crankcase. That will help your rear main leak because it is mostly luck that makes them not leak (as much) in the first place.

Are you sure you have the correct retainer for the rubber seal? It is different than then one used with a felt seal.

It's a cast retainer, and when I checked the numbers on it the second time, it correlated to a rubber seal, as I remember. It is just about impossible to get the rubber seal in that narrow opening. Heck, even the felt seal was hard to put in there, AND remove. The shop said the retainer was in good shape and flat, and the crank was in great shape. I've checked the retainer myself and am pretty sure it is in good shape.

If you have the cast iron retainers for rubber seal. They used a different gasket between the halfs also. Do the rear seals you get now have a metal stiffiner in them?

(quoted from post at 19:20:13 03/25/12) If you have the cast iron retainers for rubber seal. They used a different gasket between the halfs also. Do the rear seals you get now have a metal stiffiner in them?

Click to expand...

Metal retainer is good?

What do you mean a different seal between the two halves? The little diamond type things that sandwich between the top and bottom?

Yes thats the ones, don't know if its causing his problem, but he is looking for ideas.
Just wondered if the rubber seals you get for those engines now still have metal inside them. Used to be able to see the metal at ends of the halfs.

(quoted from post at 19:38:29 03/25/12) Yes thats the ones, don't know if its causing his problem, but he is looking for ideas.
Just wondered if the rubber seals you get for those engines now still have metal inside them. Used to be able to see the metal at ends of the halfs.

Click to expand...

Yes, they installed the little odd shaped gaskets on both ends of the retainer, that sort of held the rubber seals between two fingers of the odd shaped gaskets. Yes, the rubber seals had metal in them. They were very stiff and very hard to install. I've talked to the shop about it (they are very nice about this problem), and they suggest an overpressure, such as occurs before the rings are seated. Told me to keep the oil filler (not FILTER) loose, drive it around a bunch pulling something (don't get dust in the filler), check the blowby tube, and some other things, then get back to them. I'm not near as depressed about this as I was before talking to the shop, plus sleep helps.