Author Topic: My Other Snowmobile  (Read 816 times)

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mswyka

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My Other Snowmobile
« on: May 18, 2017, 01:12:58 PM »
Good afternoon.  Yes, it is true, in addition to the Kawasaki's  I have another  snowmobile.  In my case it is a Simplicity tractor with a snowblower.  I apologize in advance for posting  to this site, but past experience has shown that quite a bit of  information is embodied in the members of this forum.

My challenge is that the tractor has a twin  cylinder Lombardini air cooled diesel engine.  It is time for an engine overhaul.  I am fine with gas engines, but this is a little different and am wondering if anyone here has rebuilt one of these engines. 

Interceptor398

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Re: My Other Snowmobile
« Reply #1 on: May 18, 2017, 04:55:42 PM »
I have yet to do a diesel engine but they can't be that much different than most 4 cycle engines.  It will be interesting reading about this adventure as I have a 3 cylinder diesel in my IH 500 E crawler that needs a little TLC.

kawhead

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Re: My Other Snowmobile
« Reply #2 on: May 19, 2017, 03:38:32 PM »
never had a diesel anything.....I can learn from your adventure

mswyka

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Re: My Other Snowmobile
« Reply #3 on: May 19, 2017, 05:36:29 PM »
I think that it is great that an engine can go 30+ years before needing attention.  We seem to only get about 10 years between re-builds on  the gas engines.  But I have yet to find anyone, dealer included, who has actually rebuilt one of  these engines.  Kohler represents that parts are available.  And it has been suggested that it may be possible to swap in a brand new Lombardini engine.  I just don't want to be the first ever to do either.  The rest of the tractor is too good to scrap.

Lloyd (ljm)

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Re: My Other Snowmobile
« Reply #4 on: May 24, 2017, 06:21:33 AM »
Mark

 I have never rebuilt a diesel that small. I have done a couple 6 cylinder 150hp tractor engines. It is not rocket science! I'm sure you are up to the challenge.
 What symptoms are you seeing that makes you think it is time for a rebuild?
77 SST
78 Intruder
79 340 Invader
80 440 Invader
80 Drifter (bought new)
80 LTD 4/6    X2

Several Deeres

mswyka

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Re: My Other Snowmobile
« Reply #5 on: May 24, 2017, 08:45:57 AM »
Lloyd, thank you for the encouragement. I now have a parts diagram and a parts source, so the engine may be coming apart very soon.

mswyka

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Re: My Other Snowmobile
« Reply #6 on: May 24, 2017, 04:11:23 PM »
Lloyd, thank you for the encouragement. I now have a parts diagram and a parts source, so the engine may be coming apart very soon.

And yes, I am assuming need for a rebuild as a result of excessive smoking and unacceptable oil consumption.

mswyka

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Re: My Other Snowmobile
« Reply #7 on: June 09, 2017, 08:27:49 PM »
My other, other snowmobile is a Duetz Allis 912.  We use it to plow snow.  We rebuilt this particular tractor in early 2015 in preparation for taking the 7790 out of service for this rebuild.  But, a couple of weeks ago while my nephew was mowing the lawn the tractor started to behave badly.  It has  excessive crank-case pressure and blows out of the breather cover and the dip stick and will not run properly or allow mowing.  I have performed a leak down test and have very good results.  I have also pulled the head to look at the cylinder and all looks good there too.  Pressure is getting into the crankcase from the cylinder somehow, but I am not sure how and therefore don't know how to fix it.  During the rebuild we sleeved the cylinder to standard bore and replaced the valves.  Since the rebuild it has been used for mowing for two seasons and for snow plowing  for one season.

I realize that this is not a Kawasaki but I am sure that someone here knows a lot about Kohler K301 engines.

mswyka

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Re: My Other Snowmobile
« Reply #8 on: June 10, 2017, 06:52:29 AM »
I forgot to add that after calling multiple service outlets the diesel is going to my motorhead friend's shop.  He has extensive diesel experience and was the only one I found who had actually rebuilt a small Lombardini.

Interceptor398

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Re: My Other Snowmobile
« Reply #9 on: June 10, 2017, 05:36:15 PM »
Sounds like there is hope!! :)

mswyka

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Re: My Other Snowmobile
« Reply #10 on: June 10, 2017, 07:26:56 PM »
Sounds like there is hope!! :)

Yes, there is always hope.

rminier

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Re: My Other Snowmobile
« Reply #11 on: June 11, 2017, 02:46:44 PM »
 I have fiddled with several Kohler K series over the years.
My first thought is to remove, clean, and check the entire breather assembly....make sure the little drain hole on the inside plate is clear. And make sure all of the breather components are in good shape.
 Also possible a broken piston ring is allowing lots of compression pressure to blow down into crankcase.
 Here is a good forum post.  http://www.wheelhorseforum.com/topic/25963-kohler-k241-crankcase-breather/     
« Last Edit: June 11, 2017, 03:06:40 PM by rminier »
75 SnoJet Astro SS, 79 Kawasaki Invader 440, 82 Blizzard 9500, 83 Yamaha Vmax 540, 97 MXZ 670....and holding...for now.

mswyka

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Re: My Other Snowmobile
« Reply #12 on: June 24, 2017, 08:33:16 AM »
The engine is blowing out of both the breather and the dip stick tube.  My last theory was that I was getting blow by on the valve guides into the breather assembly and  then into the crankcase.  I pulled the breather cover off and ran the engine and there was nothing coming down the valve guides everything was coming out of the crank case.  I pulled the engine and pulled the piston.  Piston, rings and bore measure within specification with no evidence of blow by.  Not sure where to turn next.

mswyka

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Re: My Other Snowmobile
« Reply #13 on: July 13, 2017, 06:55:47 PM »
Update.  Diesel is still in the shop.  Gas engines are back to running.  After an intensive investigation and much fiddling, I am concluding that we got a load of bad fuel that caused the gas engines to run excessively lean and overheat.

mswyka

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Re: My Other Snowmobile
« Reply #14 on: September 23, 2017, 12:19:15 PM »
Update, Diesel Engine has been disassembled and visually inspected.

After 35 years the engine looks very, very good on the inside.  Pistons worn and one piston rod bearing visible worn.  Other than that it looks like a great engine.  Now to find all the parts that we need.