M18 spec # loc?

[squatch]

I've been chasing a seal problem in my M18 in my 1872. I have a rebuilt longblack so the info in the sheet metal sticker is not valid. The main seal I bought from Cub appears to have been a slightly smaller inside diamater than my engine. It was difficult to install and lasted about 2 minutes. Is the model and spec on the block somewhere? I don't remember seeing it while the engine was out. Motor is still in the tractor at the moment and will be for a week or 2 till I get time to mess with it. I have the old seal that got pushed out of the engine when I got fuel in the crank case. Found the rest of that problem too. I thought it was the carb float but it appears the fuel pump also leaked into the block.

[aagitch]

I thought I saw somewhere on here that there was two different size seals. Not sure if it was this engine or the KT17 but someone will chime in soon.

[ol'George]

The M18 has a slightly larger taper and seal diameter @ the flywheel end, so the I.D of the seal is larger, but the O.D. is the same.
On the PTO end of the crank, all the seals are the same.
If you have a M-18 (with no braker points) they all use the same seal.
If it is a Kt 17, they have the smaller ID on the seal.
Just look up any spec ## for the M-18 and that will get you the correct seal,
If it is a M-18

[R Bedell]

The 1872 originally had a M-18, Spec No 24506

[squatch]

I bought a replacement longblock 2 years ago. But it is an M18. I was told there are 2 different sized seals on the inside diameter. I bought the replacement using the Cub part # for my tractor from the Cub dealer. Flywheel side electronic ignition. It looked like a good match for the one that blew out. I had fits driving it in over the shoulder of the crank. But it looked ok. Shaft was smooth. I've installed a lot of seals over the years with no problems. This thing ran about 2-3 minutes and started puking oil again. Is there something special I need to know about placing this seal? Do you drive it in till it stops like most seals? Manual says 1/32" but it stops a little further than that. Do both the inner and outer lips on the double lip seal sit on the larger step of the crank? The one that came in the engine was good for 2 years.

[Matt G.]

Did it push the seal out or is it just leaking? Have you checked to make sure that you have a vacuum in the crankcase? Use a vacuum gauge or rig up a manometer and make sure the breather is working right. If it isn't it can blow the seals out.

[R Bedell]

You didn't say if you bought the Long Block new or used. If it was new, then there was a Spec Number that was provided.

You say you have the old seal, then you may have to see if there are any markings or numbers on it. You could also take the seal to your favorite Seal Warehouse and have them match by physical size.

You could also scour the Kohler site and see what the differences in this seal are. See.... Kohler

[ol'George]

All good ideas mentioned, possibly you were sold the smaller seal by mistake.
OR if it was the correct seal, and you were having trouble getting it over the crank, the lip was possibly damaged during installation.
I would say this seal installation would be typical of any seal replacement, and it should be flush with the case.
I have seen where sometimes a seal gets cocked during the installation then becomes distorted and consequently leaks.
I am attaching 2 pix's, one is of the different crank tapers/seal diameters, and they are close.(larger on the left)
The other pix. is of the case "pocket" where the seal lives.

[squatch]

I bought a rebuild longblock from a Kohler rebuilder. It was a direct replacement for my Cub and has worked fine. I don't have a spec # on the paperwork.

Last fall I found the crankcase fuel of gasoline. Unfortunatly I ran it a short bit not knowing what was going on with the crankcase. I rebuilt the carb and found the tip on the float valve ate up from E10 fuel. It was running well for the little I used it afterwards. I found no more fuel in the case and figured I had the problem solved. Used the tractor to move some snow over the winter with the blade. Running well and no problems. Next morning I attached the 450 blower and did 2 passes down my road and the tractor started billowing smoke. At 1st I thought it was a belt but checked and found oil draining on the road fast. I got it back to the garage and that was it before I lost oil pressure. It was not run without oil pressure.

When I pulled the motor everything on the flywheel side was covered with oil.
When I pulled the flywheel the seal was just sitting on the shaft. Outside the pocket. I'm working on the assumption that it was pushed out most of the way when the crank case was full of gas. I probably finished the job when I ran the snowblower and put hard stress on the motor.

I just replaced with a seal from Cub for my make and model. A quick side by side it looked like the one I took out. Installed the new seal and it was running like a top then started puking oil again. It may be the seal was slightly too small ID. It didn't go in easy for sure. Once again I'm assuming it's that seal. I haven't had a chance to deal with it yet. I'm also getting a fuel smell from the oil again but the crankcase is not flooded.

I have another new fuel pump that I will be installing. I figure either it was the original problem or the diaphram was blown by the flooded case. This issue has lingered for months as I've got a million irons in the fire right now so I'm not getting much time to mess with it.

I already checked the seal that came in the motor that lasted 2 years. It is a NOK (Chinese) BE1177E seal. No one has been able to cross reference it for me yet. No luck on web search either. I also checked the crank breater and all is clear and as it should be. Haven't done a vacuum test yet but don't believe this is the problem now.

Thanks for the pics I think I just have the wrong size seal this time. Man I'm tired of pulling the engine in this tractor. I've done it way too many times now.

[R Bedell]

Manufacturer: Freudenberg-NOK

Seal No: Freudenberg-NOK #BE1177E

Freudenberg-NOK
General Partnership
47690 East Anchor Court
Plymouth, MI 48170-2455
Phone:1-800-533-5656

USA URL: http://www.freudenberg-nok.com/

NOK Corporation
Japan URL: http://www.nok.co.jp/e/index.html

This should get you some information.