Rebuilding engine from 1972 140 H3 ... Southwest Wisconsin

Tomorrow I need to get engine pulled and delivered to local small engine repair shop. Shop owner will teardown the engine and determine if it can be rebuilt. If yes he will tear down and mic the components to determine machining require to rebuild. The machine shop he had used in the past appears to have closed their doors. He has one other option and I guess I will be the guinea pig to see if they do acceptable work and he continues to use them.

I am confident engine can be rebuilt. Not sure I agree with repower options.

I was surprised how clean the fins were when I removed the tins to pull the head. I don't know if the head gasket had been replaced. I bought this tractor for a very reasonable price knowing it would probably need engine rebuild. Repaint engine probably not because I am not doing the rebuild. I had a K301 from a 120 rebuilt last winter and tractor really impresses me with 50 year old patina. Sheet metal and hood on this 140 are not as good as the 120 and will need buffing and wax. Hood is broken up and will need bondo work. First need to get a 318 project completed. Don't expect to get engine back until April/May which is fine. Gives me time to finish up other started projects. I have many.

Also own a 1973 140 H3 that I took fender deck to a powder coat business. I was very dissatisfied with the job they did. That tractor will probably get a repaint/powder coat. Unsure of condition of engine in that tractor. I have not had it running yet.

Engine is out and in back of truck. Oldest son came to assist. I could not lift it myself.

Can't believe how clean the frame is under the engine. I highly suspect this is a replacement low hour engine but don't know reason rod failed. Tractor is back in garage so I can do some clean up on it tonight then will get pushed outside and covered. I need to go through complete tractor to make sure everything works as intended like I'm doing with the 318. I know the steering needs attention. Looseness in steering is not caused in gearbox. With the engine out I can see this is excessive movement in the linkage. But tomorrow I need to get back on the 318.

Old&Rusty said:

I know those 14 hp kohlers are heavy, and it does look pretty clean in the engine compartment

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I could lift it myself but with broken rod the crank wanted to spin freely and I could not stabilize it as I lifted it. When I got back from Jim's Bryan was already here and had it lifted into truck. I'm a wuss.

Gavin L said:

Maybe the engine block has some numbers that could tell a story?
I have yet to see that clean of a engine….🤣

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I did not see any stamped #'s on block but did not really check that close. Will look when I unload engine tomorrow morning.

Engine has been delivered to local shop. It will be torn down today as machine shop was waiting for it. Machinist is on snowmobile trip this weekend so it will be delivered to him next week. Seems like this engine will get a quick rebuild (if it can be rebuilt). Jim is also comfortable that it can be rebuilt. Crankshaft spins freely with no noise or grinding feeling. He says I can stop out and have a look at it disassembled late this afternoon.

And now for the rest of the story

The good news is that the engine can be rebuilt.

The rod broke both sides in the radii where the rod narrows just above where it bolts to the crank. The oil slinger that is part of the cap also separated from the cap. All these pieces including the cap fell into the well where the slinger operates to splash oil on engine components. The rod/piston got pushed up into the cylinder so there was no stub remaining to poke a hole in the block. The cylinder has no major scars and just a hone should clean it up for reuse. Doesn’t sound too bad except …

The reason the engine and tractor are so clean is the engine has been rebuilt maybe a couple of times earlier. It is the correct block for a 140 because it has provisions for balancer gears but balancer gears were not reinstalled after rebuild. The cylinder is bored .030” over so is at max size. The crankshaft is ruined and needs to be replaced. Will need complete .030” over rebuild kit. The stator has numerous bare wires and needs to be replaced. Last item needed would be a pto clutch.

Repair options would be,

• Bite the bullet and spend the money to build. Jim thinks he will be able to rebuild for close to same cost as the K301 in the 120. Negative fact is engine will be on its last rebuild because of oversize piston/rings.
• Find replacement K321AS engine from a 140. Needs to be this engine as newer K321AS engine (Deere 314 engine) does not have balancer gears. Balancer gears are needed in the 140 as the engine is bolted directly to the frame. The 314 engine is mounted on isolaters. No balancer gears on 140 would make the tractor a rattle trap.
• Repower kit. The only ones I am familiar with are Briggs which you couldn’t give me because to mount the engine in a 140 the end of the air cleaner is cut off to clear the fuel tank. Air filter is left open to outside environment. An accident waiting to happen. The other engine I have read some articles on is the Predator from HF. Made in China. No replacement parts. Won’t happen here.
• Scrap tractor and engine.

I do not like to scrap these tractors. Repower kit is out. Told Jim let’s go with rebuild. He will look for crankshaft and balancer components needed. There is currently a crankshaft for sale on eBay for just north of 100 bucks. Jim has dealt with this seller before and feels he is a reliable source. If we cannot find a crankshaft we will look for a 140 engine to rebuild and install in the 140.

I will keep you updated.

Me, I would pursue the rebuild first, too. When completed, you will have a completely known-quantity that you can rely on. This engine may be on its last rebuild, but your 140 is unlikely to be racking up high hours given you have other machines. You just need it to operate reliably for occasional use. It will last a lifetime with that kind of usage.

Old&Rusty said:

I know those 14 hp kohlers are heavy, and it does look pretty clean in the engine compartment

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His model number indicates it is a single cylinder cast iron Briggs and Straron.
Walt Conner

One fact I neglected to post was the previous rebuild did not use Kohler parts. No markings on rod/piston to indicate where parts came from. The piston had a crack thru one of the wrist pin bosses into the bore area. We could not tell if the crack was there before or after the rod broke. This is an example of why I do not like using after market manufacturers parts. Yes, you can save some money but you loose quality, I would rather pay more for the quality and warranty. If we find all the parts to rebuild, the rebuild kit will be Kohler.

I have asked another local MTF member to help me contact the seller of this tractor. I talked to him after the rod broke and IIRC he thought he may have a K321 to use as in rebuild. Doesn't hurt to double check.

Put the 140 back together. Hardware is only finger tight. Need the 140 out of the garage so I can work on the 318.

Tractor has an automotive battery which is size wise too large. Hood will not close.

Tractor is covered and waiting for engine.

GreenGabby said:

Put the 140 back together. Hardware is only finger tight. Need the 140 out of the garage so I can work on the 318.

Tractor has an automotive battery which is size wise too large. Hood will not close.

Tractor is covered and waiting for engine.

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Looking good----But I thought that all the 9 bolt heads like your cyl. head--were a K341? =16HP