Rear Main Seal

   / Rear Main Seal #1  

N8-126

New member
Joined
Mar 23, 2008
Messages
23
Location
Sunbury Ohio
Tractor
YM155D
I have a YM155D. I just rebuilt it head to toe, I basically went to Hoye and ordered every part they sold for the tractor and put it back together again with new parts. In my mind it was better to rebuild an old workhorse than to spend big bucks for new one.

The rear main was leaking before the rebuild, and 3 seals later it is still leaking. I want to fix it, but throwing money at new seals and splitting the tractor doesn't seem to be doing any good. Does anyone have any thoughts about what to do next. I hate the thought of damaging the completely new clutch assembly that I just put in.
 
   / Rear Main Seal #2  
I have a YM155D. I just rebuilt it head to toe, I basically went to Hoye and ordered every part they sold for the tractor and put it back together again with new parts. In my mind it was better to rebuild an old workhorse than to spend big bucks for new one.

The rear main was leaking before the rebuild, and 3 seals later it is still leaking. I want to fix it, but throwing money at new seals and splitting the tractor doesn't seem to be doing any good. Does anyone have any thoughts about what to do next. I hate the thought of damaging the completely new clutch assembly that I just put in.

Did you replace the rear main housing?

Danny
 
   / Rear Main Seal #3  
Are you sure it is leaking from the seal? If so, is it leaking from around the crank area or the outer seal area?

Aaron
Hoye Tractor Parts
Contact Us
(940)592-0181
 
   / Rear Main Seal
  • Thread Starter
#4  
Both are very good questions. I didn't know replacing the rear main housing was an option until I tore into it the first time and at that point I didn't see anyone (on the internet) that appeared to sell them.

Regarding where it is leaking from, I don't have a clue. I am not a diesel mechanic by any means, so tearing it down is quite an ordeal for me. Especially with the front end loader coming on and off each time.

Last go around it seemed like it was leak free and I am not smart enough to start it without the bell housing attached. I am basically at a loss because I can's see it when it's running to tell where the leak is coming from.
 
   / Rear Main Seal #6  
Nice looking tractor. I dont think Danny was probably suggesting that you needed to replace the housing. It is not a common rebuild part. He may have just been suggesting that may be the source of the leak if not re-installed correctly. I think you will need to clean it up good & figure out where it is leaking. If you cant start it- maybe you can just way overfill it and see if it will leak that way. Possibly filling it up with diesel or something thinner than oil will show a leak faster (dont start it that way though).

Aaron
Hoye Tractor Parts
Contact Us
(940)592-0181
 
   / Rear Main Seal #7  
On the YM155 tractor the oil pump is located on the rear of the engine and you have to split the tractor to get to it. It looks like you are going to have to split the tractor again to find your leak. Examine everything very closely; perhaps the oil pump is cracked or the gasket may be leaking.
 
   / Rear Main Seal
  • Thread Starter
#8  
Being that she has been torn apart for the last 6 months, I would like to use the old girl for a while before splitting the case again. If I keep running it and just keep a close eye on the oil level, am I risking damaging the clutch (I replaced the entire assembly including flywheel when I had it apart) or anything else. I noticed last night that the flywheel is flinging oil up onto the start and oil is thus dripping out of the bottom of the starter-I don't want to replace the starter, I think it is the only thing I didn't replace during the rebuild.
 
   / Rear Main Seal #9  
If it is leaking bad enough to be running out of the starter that soon it should be pretty easy to spot where the leak is coming from. I dont think you will damage your clutch other than it might slip more. You can gum up your starter though. The leak could also get worse quickly and you could run out of oil (those dont hold much). Personally I would split it again & check it out. Fairly simple fixes can get expensive very quickly. Your probably getting pretty good at splitting it so it shouldn't take very long :D.


Aaron
Hoye Tractor Parts
Contact Us
(940)592-0181
 
   / Rear Main Seal
  • Thread Starter
#10  
Right, if only that were true. It will take me at least a week.

Aaron--I think you helped me quite a bit when I was buying parts. I believe that I talked primarily to you and Matt. Sum total I spent about $2500 on parts. Our most memorable email exchange may have been the one regarding rear rims and tires. The 1980 Ford 1210 rims and tires are a perfect fit for the YM155D and they are still available through local New Holland tractor dealers. If you look closely at the pictures that I posted you will notice that the rims are a slightly different shape than the standard Yanmar rim.
 
 
Top