Kohler CV730 motors POS

[JimR]

I just picked up a Husqvarna GT2548 with the Kohler CV730 25HP engine in it. I stole the machine for cheap money. It has 210 hours on it and has a blown connecting rod. the previous owner told me that he had the cylinder head gasket done when it was new because it was leaking oil. My research on these motors tells me that there were lots of problems with them. That being said, I have found a CV30 short block in great shape. Does anyone know if the CV30 and CV730 have the same short block? TIA, Jim

 

[mikehaugen]

not sure about the blocks, but I bought a bunton mower on it last year with a 25hp kohler- I believe cv740. The guy I bought it from thought it had a broken connecting rod, turns out the rocker arms had come apart on one of the heads. No other damage was done except needing a new head, valves, rocker arms, and pushrods. Like you, I did a lot of research and found this to be a quite common problem.

 

[JimR]

From what I have gathered on the internet about the Kohler 25HP motors. The Kohler motor is no longer the Kohler motor of yesteryear. I also own a 1995 Cub Cadet with a Kohler 18HP V-Twin motor. This motor has been a dream. The previous owner and I have never had a problem with it. So far I have found quite a few people that have had connecting rod problems with this motor.

 

[JimR]

Today i took this 25HP Kohler motor apart. The first thing I noticed after pulling the flywheel was that the flywheel key was sheared off. I then proceeded to take the rest of the motor apart. What I found inside was just incredible. The inside looks like it completely exploded at about 6k rpms. I found two broken connecting rods, sheared camshaft, broken piston skirt and a broken block from where the connecting rod hit the cylinder wall. Both connecting rods had parted ways with the piston pins. One was completely broken off the crankshaft. Never before in my life have I seen such damage to a 2 cylinder motor. I can only assume that the previous owner ran this motor with one **** of a knock for sometime before it exploded. The dipstick showed it was full of oil. I will try to post some pictures of the parts after I clean them up a little bit.

 

[TimberXX]

Any photos of the damage jim?

 

[JimR]

Sure do now. up, Photo enclosed . It appears that the motor was run low on oil by the previous owner. Kohler told me that the oil comes down from the top of the crankshaft then into the connecting rods. One thing that surpised me is that the other rod has no scoring on it. Yet it broke away from the piston. There is a slight bit of scoring on the top crankshaft journal which tells me lack of oil. The top connecting rod transferred metal to the crankshaft causing it to fail. The rest is history, because when you are running a motor at full rpms and something breaks all "H" breaks loose inside. The disintigrated connecting rod is sitting just above the connecting rod journal.

 

[JimR]

I bought another Husqvarna GTH2548 with a blown motor shortly after buying the first one with the intentions of building one really good machine out of two. Both were bought for a few hundred dollars each. I took the motor apart yesterday on the second machine. It was blown up, but not as bad as the first one. I think the block is salvageable on this one. The cam and one rod/piston are still good. This one also threw a connecting rod. The piston was destroyed. Tonight I was on EBay and won a brand new Kohler 27HP short block with gasket set for $401.53 delivered. The short blocks on the 25 and 27HP motor are interchageable. I should have that by the end of the week. Things are looking up. I also was able to clean up the first crank that is pictured above and the one I took apart yesterday. The second one was in really good condition compared to what the first one looks like.