12hp engine problem.... - Page 3

Merk · #21 02-06-2013, 06:27 PM

If it was my tractor I would remove all items connected to engine...clutch, pto clutch and starter. Remove one at a time and try to spin the engine over. Maybe one of the above is causing your drag. I would remove the pto clutch first. If none ot the 3 is causing the drag on the engine you will have to take engine apart. When you remove the piston spin the crankshaft to see how free it is.

I had a Kohler K321 that made a noise after it ran a few minutes. The problem was the crankshaft bearing on the pto side. I've had a few that the bearing in the pto was bad and cause a noise and not leaving the pto clutch release.

Before you take the bearing plate off check to see how much crank end play is. A way to check crank end play is the way a Kohler manual shows.

You can download a Kohler manual from the site's Technical Library.

It is hard to tell what the problem is without having the tractor/engine in front of me.

Sam Mac · #22 02-06-2013, 06:41 PM

Gotta be something wrong with the “ Piston re-install” if it was running OK before he replaced the head gasket, pan gasket both of which would have little or no effect on how it ran. Gotta be something to do with how the piston and rod went back in after it was removed and cleaned. Just my 2 cents.

WoodMaster · #23 02-06-2013, 07:28 PM

I think Sam Mac is right, although, I will try spinning the engine after everything is disconnected. I guess I could of put the rod cap on backwards??? Someone mentioned the piston is directional too? That I did not know. Planning on digging in on Sunday. Thanks to all of you for sharing your expertise!

OldSchool81 · #24 02-06-2013, 08:37 PM

Quote:

Originally Posted by Matt G.

It cannot get in through the rings...the bore is over an inch above the carb on these engines. If the needle and seat in the carb malfunctions on a K-series single, the fuel takes the path of least resistance out of the air cleaner. The only way for gas to get into the crankcase on these engines would be past the intake valve guide, and there's no way very much (if any) could go that way because the easy way out for the gas in this situation is out the atmospheric vent and out of the air cleaner.

Yes, you have a good point. I was looking at my motor today and yes the situation presents as you have described. I was just hoping that he didn't have to tear her down again and could check the small stuff first.

WoodMaster · #25 02-08-2013, 02:02 PM

It looks like you guys were right on all accounts... The rod cap was on backwards. I also noticed oil on the piston head (see pictures). The cylinder wall looks fine. Is there anyone in this conversation that is a parts dealer? So rings, rod, should I just do the entire piston? Is it necessary to go 10 over? I'd rather not, unless it is the consensus....

Thanks!
BP

Sam Mac · #26 02-08-2013, 02:13 PM

Time to mic up the bore and rod journal. Where do you live in CT? If your close to Waterbury I know a good engine shop.

WoodMaster · #27 02-08-2013, 02:17 PM

North Branford, about 40 minutes away.

Sam Mac · #28 02-08-2013, 02:40 PM

This is the guy that used to build my race car engines

Bill Carlquist Carlquist competition engines 1-860-274-0742 in Watertown Tell him Sam McCleary sent you.

Sam Mac · #29 02-08-2013, 02:59 PM

This is another option for you. A 12 for sale.

http://frederick.craigslist.org/grd/3546406534.html

Matt G. · #30 02-08-2013, 05:07 PM

Without you even measuring anything, I can see a pretty big gap between the piston and bore, so the piston is probably worn, but you'll have to measure it to be sure.