Picked up a 12hp shortblock

Fri Jun 11, 2010 10:37 am

I picked up a 12hp kolher shortblock for rebuilding yesterday. The crank and connecting rod feel perfect. Then i look at the bore which is scored. With the bottom end in good condition it leads me to believe it was run with a bad air cleaner or no air cleaner at all so dirt got into the cylinder. I think keeping the air cleaner clear is as important as checking the oil level to make sure its topped off. These is no short cuts in doing maintance nor keeping these awesome engines maintaned too.

Check you oil level before starting it up to use it. I like to pull the dip stick everytime i gas it up. Then i'm sure its ok. Its a good habit to get into.

Ocassionally I pull the air cleaner and either replace it or blow it out from the inside so the dirt goes away from the element and not thru it from blowing the air into the inside. Remember to do it right and make sure you check it often. Just keeping on top of the maintance will make these engines last a longtime. Remember there not manufacturing these engines anymore and soon the replacement parts will run out too. So keep your older kolher engine in tip top condition.

The guy i purchased the engine from just restored the cadet and he purchased it not running. This is his first cadet and he is bitten by the cadet bug already. Its great to see the new guys catching the cadet flu too. I have to add he did a great looking restoration job on his 129 cadet.

Re: Picked up a 12hp shortblock

Fri Jun 11, 2010 10:46 am

Good tips and advice. I'm sure you'll gets your engine rebuilt real nice.

Re: Picked up a 12hp shortblock

Fri Jun 11, 2010 9:35 pm

I purchased a boring setup so i can do my own boring like i have done in the past. I can punch it .010" over in minutes. I also purchased the extra fine stones and the coarse stones for it too so i can open up the bores even faster.

Re: Picked up a 12hp shortblock

Sun Jun 13, 2010 10:09 am

Every cub cadet i purchase needs a headgasket. I pulled the head from my 108 cadet and seen a few score marks and its been puzzling me why were the marks in the cylinder. The crankcase oil is clean and the PO did the maintenance plus he was the orginal owner too. I see the same condition in this 12hp kolher too(cylinder). Finally it dawned on me its dirt thru the air cleaner element thats doing the galling and scoring.

If we think about it the mower deck does scalp sometimes and it throws up dirt and if the air cleaner has holes in it the dirt can get sucked thru it into the cylinders.

Re: Picked up a 12hp shortblock

Mon Jun 14, 2010 8:01 am

When I had the engine on my 1450 rebuilt I had that issue. You could see severe wear on one side of the piston - close to the intake valve. The bore was OK but the piston looked like it had been torched. The guy I had assemble the engine said it was from dirt and if the air filter had been kept properly in place he would have just ground the valves and put it back togather. The bore was lightly honed (still standard) but the aluminum piston was trashed without a thought of just reringing it.

Re: Picked up a 12hp shortblock

Tue Jun 15, 2010 9:11 pm

I make sure the gasket between the iar filter housing and the carb is in one piece and good too. Sometime these gaskets are MIA too(missing in action). I get my gaskets at www.tulsaenginewarehouse.com I'm disabled and can't walk too far so i mail/internet order most of my parts were i can. BB

The air filters are at advanced auto parts and priced affordable too.