107 engine: what happened? Should I run it? Or swap it?

[Cubcadet_107]

So I got to work on my 107 changing the slightly watery oil (still cannot figure out how moisture keeps building up inside the crankcase!) and it was going well, but as it turns out this engine has sludge built up in the bottom of it. Now the thing did sit for 30 years, but the trouble I'm having is figuring out whether or not there's metal shavings inside the sludge.

I have not run this engine at all with water in the crankcase, or at least not with enough water to turn the oil white, which should be zero water. The drained oil does not seem to have any oil shavings in it at all. I've even rinsed it out a bit with some fresh 30wt and still no signs of metal shavings in the bucket. When I stick the dipstick down through the hole on the camshaft side of the block where the fuel pump would've mounted if it was needed, I can scrape up the black colored sludge. Upon wiping the sludge onto a paper towel, I find what MIGHT be a few shavings, or no signs of anything. The sludge also turns to a very dark gray color when spread onto the paper towel.

Further analysis reveals that a magnet will not pick it up, and nor will a metal detector detect it. The con rod cap does have the oil hole facing toward the camshaft like its supposed to, and where the con rod and cap meet, there's 2 small notches on the edges of either side where I can just see bits of the rod journal through the holes. In those spots everything looks fine, although of course you can't see the middle at all. There is almost no play at all between the con rod and crankshaft, although there is a slight bit of play between the conrod and piston.

So, all in all, I'm at a loss on what to do here. Run it? Or swap it? I have the basis of a K301 laying around minus all the outer additions, should I swap it in and dismantle my k241? I know the sludge turns to a dark gray when spread out, but any in engine I've seen that's definitely got aluminum shavings in the oil, the gray color is a lot lighter. Plus it only shows up near the bottom of the sludge, and not in the actual oil. Perhaps this is some break-in shavings from when the engine was being broken in 30 years ago, that then sat and settled into the sludge in the bottom of the pan? Or maybe its actually pieces of the piston because it has so much slop in all directions? I'm at a loss here, and I don't want to find out what it is by having the rod go on me. Anyone have any ideas or suggestions?

[darkminion_17]

Pull it, clean the out the sludge, add new oil, and run it till it blows!!! Or not....

[Cubcadet_107]

Originally Posted by darkminion_17

Pull it, clean the out the sludge, add new oil, and run it till it blows!!! Or not....

well, that's the issue, I don't really want to run it til it blows. This tractor holds more value to me than any of my other machines, and the last thing I want to do is blow it up.

I appreciate the insight though!

[green407]

Mix up some diesel and transmission fluid at about a 1:1 ratio and run it in your engine far 10 - 15 minutes at low throttle, drain it and inspect.

[Cubcadet_107]

Originally Posted by green407

Mix up some diesel and transmission fluid at about a 1:1 ratio and run it in your engine far 10 - 15 minutes at low throttle, drain it and inspect.

That's an interesting suggestion, but to me it sounds like it might do more damage to the engine than good? Would hydrostatic fluid be a good supplement for transmission fluid, and does it matter the age of diesel fuel? I know we've got a can of diesel laying around but it has to be a couple years old at this point.

[darkminion_17]

Swap it then, but you will always wonder how long the that one will last till it blows up.

[Cubcadet_107]

I might just bite the bullet and swap the engine. Then perhaps take it to a well-respected rebuilder who will do it RIGHT instead of putting a standard piston into a sleeve that's .010 over (I checked, it does indeed appear to have a sleeve installed) like the last rebuilder did.


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Here's the engine I have, its a Kohler K301 out of an unknown Cub, it was mounted in my parts 105. Not in horrible shape, and its complete and turns over. People it came from are a big Cub family, and the engine did run well before they parked it. I guess it didn't have anything wrong other than the absence of a carb, tank, and starter/generator. However, as you can clearly tell, while it was sitting it puked most of its oil out the rear seal and all over the back side of the engine, so I'll be needing a gasket and seal kit. Not sure how the oily mess managed to climb up the cooling fins either.

To swap it in I would install all the k241's shrouds, carb, air filter, gas tank and mounts, head studs (because this k301 has all bolts except for the one over the exhaust, probably because it's stuck in there), coil, condenser, Starter/generator, and basket pulley. New seals and some new gaskets, new head gasket, spark plug from the k241, perhaps the whole head from the k241 depending on the condition of the current one. From what I can see, it won't be very difficult to at least get this engine dropped in and functioning.

The k241, well, that's gonna be a bit of a challenge to say the least. I will definitely rebuild it or get it rebuilt, because I do want the tractor to retain the engine it came with.

[Cub Cadet 123]

If your engine sat for 30 years and had sludge in it, then you could have a ring or rings that are stuck allowing things to mix with your oiiiillll. Drain enough of your oil out to add about 1/2 quart of Marvel Mystery Oil in your crankcase. Run it at LEI for a few minutes, then drain out all oiiillll and refill with Kohler 30w. Then place a magnet sheet on the bottom of your oiiiillll pan to hold metal shavings in the lower part of your crankcase to prevent them circulating in the engine. Keep in mind the magnet won't totally prevent all of the metal shavings from circulating since the depth of the oiiillll pan is not that deep, but it may help prevent some of them. Then, as my Uncle Lewy said.....run it and enjoy!

Cub Cadet 123

[Cubcadet_107]

Originally Posted by Cub Cadet 123

If your engine sat for 30 years and had sludge in it, then you could have a ring or rings that are stuck allowing things to mix with your oiiiillll. Drain enough of your oil out to add about 1/2 quart of Marvel Mystery Oil in your crankcase. Run it at LEI for a few minutes, then drain out all oiiillll and refill with Kohler 30w. Then place a magnet sheet on the bottom of your oiiiillll pan to hold metal shavings in the lower part of your crankcase to prevent them circulating in the engine. Keep in mind the magnet won't totally prevent all of the metal shavings from circulating since the depth of the oiiillll pan is not that deep, but it may help prevent some of them. Then, as my Uncle Lewy said.....run it and enjoy!

Cub Cadet 123

That's an interesting theory. But here's the state of the engine. At this point there is no oil in the crankcase. It had moisture getting into it. The rings are not stuck, however the piston is about .010" too small all the way around for the bore (poor rebuild quality I assume) and there is definite blowby out the crankcase vent when the engine is running because of this.

My question would be, where on earth would the metal shavings even be coming from?? And also, they don't seem to be magnetic based on my testing, so I don't think a magnet sheet would work well.

[Ambush]

If you plan to swap it, you have to pull it anyway. Why not pull it apart and check/clean everything? Might be just as easy to fix the original instead putting time and money into the donor.