Can high oil level cause rear main leak ?

[Arky217]

I have a L4200. When I got it, it had 707 hrs. on it.
I changed all the fluids and when I changed the engine oil and filter, I put in the specified 6.3 quarts. After running it a few minutes, the oil level was just barely above the low mark. I kept adding oil until it reached the full mark. It took a total of 8 quarts. Other 4200 owners have said that they also use 8 quarts for an engine oil and filter service.

Until yesterday, I have ran the tractor only about 6 or 8 times for no longer than about 30 minutes at a time. But yesterday I ran it for about 4 hours and at the end of the day I noticed an engine oil leak coming down from the rear of the oil pan. I assume the rear main seal has started leaking.

Could I have brought this on myself by putting the oil level at the full mark instead of just using the specified 6.3 quarts (which is just slightly above the low mark) ?

(I wonder that because I just read a past post where a owner also thinks that running his tractor with the oil level at the full mark caused the rear main seal to start leaking and that now he says he runs it with the oil half between the low and full marks and has not had the problem anymore.)

Is there any way to slow this leak down without replacing the seal ? Would draining some of the oil back out to the 6.3 quart level help now or is it too late for that ?

Is there any oil additive that would slow down the leak. (It,s not really bad yet, but I'm sure it will get that way, now that it's started.)

I have never really got a good answer from anyone, including Kubota, just why 6.3 quarts is the specified capacity when it takes 8 quarts to bring it to the full mark.

If I have to replace the rear main seal, once the tractor is split, does the seal come out from the rear, or is it necessary to drop the oil pan ?

Thanks,

 

[Treemonkey1000]

I will leave a more informed answer to some of the other guys on here that know way more than I do. I do believe too much oil can cause you grief though as far as rear mains in vehicles. The rear main may have just finally gotten warm enough after running it for several hours to loosen up and leak on you. The tractor was on good flat ground when you were adding the oil I take it?

 

[Arky217]

Yes, the tractor was level.
Why the specified amount of 6.3 qts. does not match the full mark is a mystery to me, but as I mentioned, other owners have experienced the same. I figured that as long as the level is not above the full mark, there should be no problems, so that's why I brought it up to the full mark. On every engine that I've ever heard of, the amount of oil to reach the full mark is the amount that should be in the engine.

I did drain out enough oil so that the level is now half way between low and full, but alas, it is still leaking.

Not that it's leaking enough yet to be a significant expense to replace, but I dread that it will get on the clutch.

Has anyone had any success with an additive to slow the leak on a rear main seal ?

 

[Arky217]

I might add that when I bought the tractor, it definitely did not have a leak and the old oil was all the way to the full mark.

The tractor had been sitting for several months, if that may be a contributing factor.

 

[oldnslo]

Arky,
yes to much oil can cause seals to leak. On your engine the question is how much is to much. Did you see any signs of excess oil coming out of the crank case breather. Usually if an engine is over full of oil there will be oil coming out the breather.

Seal sealer, good luck.

Roy

 

[VALENT]

I would haphazard a guess that the additional oil didnt create/show the leak but the new clean oil is the culprit. You can definitely try some of the leak stop additives but I dont really know their effect on everything.

 

[RoyJackson]

I can't answer the question about high oil level causing a rear seal leak...wouldn't seem likely, but I don't know.
However, excessive oil in the sump can result in the oil frothing (mixture of oil and air) by the crankshaft throws. The trouble is the oil/air mixture doesn't lubricate the main bearings...you can wipe the bearings like this.
You're better off a quart low then a quart above the max line on the dipstick.
When I change the oil in any of my engines, the dipstick will measure minimum to ½ way up between Max/Min markings

 

[LRTX1]

I know nothing about your tractor. But I did stay at a Holiday Inn last night. I would guess that the difference in quanities is in the oil filter. The manual might suggest to fill the filter before replacement and their 6.3 quart would be from that point on. Just a guess.

 

[Arky217]

WHAT A RELIEF !!!

Turns out the oil leak was coming from the T fitting that I installed in order to hook up an oil gauge !

Thought I had it tight enough (didn't appear to leak when I installed it), but after wiping everything off and watching for where the oil was coming from, I traced it back up to the fitting.

Thanks everyone for your replies,

 

[VALENT]

that is a happy ending