Kohler k321 blowing smoke
Posted February 06, 2016 - 01:11 PM
- Traill95 said thank you
Posted February 06, 2016 - 01:38 PM
Ummmmhhh . . . rebuild your engine?
Posted February 06, 2016 - 02:14 PM
Yep sorry to say it but That is Blow By.Your rings are worn out.And more than likely it will need to be Bored out.
Once you tear into it you can expect to spend alot more money than you thought.I had around $600 into the rebuild of a K301 a couple years ago.I did have to have my crank welded up and ground and cylinder bored and new over sized piston,rings and another connecting rod and replaced the Cam.
All of that because it was hard to start and it smoked a bit.
Found that my Cam had a cracked and belt ACR which was causing the hard cranking issue.Got it all together and running and sold the tractor for what I had into the engine Oh well atleast it will live another 30-40 years.
Posted February 06, 2016 - 02:16 PM
$600 is a worse case scenario.Yours might just need a light hone and a set of new rings.
Posted February 06, 2016 - 02:25 PM
Posted February 06, 2016 - 02:41 PM
The guys that answered know a lot more than me. But to answer your question there are some things you can try besides rebuilding. I use 30 wt. oil year round and keep the level halfway between the marks, i.e. not over full. I also throttle down when backing up or just driving, in between active working to give it a break.
There are other things like adjust timing, and some other adjustment type things i forget what but some guys have been lucky getting rid of big smoke and not rebuilding.
Of course i don't really know what i'm talking about having never rebuilt one, just some little things that have helped me, good luck
also i run about an ounce per gas gallon of MMO, also you try some in the crankase, might free up the rings, worth a try. and i never run it at low idle, always fast idle, the smooth spot where it doesn't shake so bad, on up to full throttle when really pushing something, good luck
Edited by Oldford, February 06, 2016 - 02:44 PM.
Posted February 06, 2016 - 02:44 PM
Couldn't it be something simple like a blocked oil drain hole in crankcase breather area? Gonna pull carb off and inspect I guess?
Could be, worth a shot.....but doubtful
I got away with just buying a piston and rings for mine.......
- Alc said thank you
Posted February 06, 2016 - 02:52 PM
the last 6 motors I took apart 5 of them the rings end gap was aligned with in a 1/2".
They all had blow by.
Most of them the ring gap was around .030 and 1 had a ring gap of .010.
I checked the cylinders, pistons and rods all were in good shape.
I set the ring gaps the way they were sub-post to be and honed the cylinders and put back together.
Them run good now with no blow by.
hope you are lucky too
Edited by lyall, February 06, 2016 - 02:53 PM.
- Alc and WNYTractorTinkerer have said thanks
Posted February 06, 2016 - 03:45 PM
So, what this is really telling you is, you won't know until you get into it.
- EricFromPa said thank you
Posted February 06, 2016 - 04:09 PM
I have a M12 here, (same thing as K301 except it has electronic ignition without points, takes most of exact same rebuild parts as a K301.) I had it bored 0.010", crank cut the same 0.010", new piston, rings and rod; I rebuilt the carb including bushing the throttle shaft, has a new exhaust valve and (I forget which) either both new seats or new guides, and a NOS, steel governor gear. using all OEM Kohler parts. At one time i had the reciepts all together but can't find them at the moment/ so I lost track of actual investment. But, as I remember, I am into that engine for right around $500 including machine shop bill, which (about 3 years old now) was like $140 of that amount.
That motor sits here, I have yet to add oil or fire it up since the rebuild, it is an identical, ready-backup for the engine on my Woods ZTR. but with other current issues that have come up on it, IDK if it will be here long enough to kill the original one that is still going strong... so it may find a home on something else.
OCCASIONALLY, a NOS brand new cast iron 12HP Kohler pops up on there, and they are usually anywhere between $1200-$2000+, the highest of which being a direct exact replacement for either an older Cub cadet or Deere GT. I see idiots on Ebay trying to get more for just a used engine with unknown hours or maintenance history, some of these even without carb or starter or coil; just a used short block.... so for the same money, a little bit of your own blood sweat and maybe a few tears, you have essentially a brand new engine for the price. Do we like putting that much into an old, 1 cylinder engine? NO. But it's cheaper than a rare/hard to find brand new replacement just like it, and all clearances restored to the tolerances of a brand new engine, ready for another 30-40 years of dependable service if built right and treated right.
What's the alternative? a Throw-a-way like a Predator that (at least I) have no idea where to get normal maintenance parts, an engine that is much lighter weight which will screw up the dynamics of some machine without that extra mass, that you have to jury rig to "make" fit, then when it blows up or needs some minor repair, what then? Throw it into a pile and buy another complete new throw a way? There are people out there that "fly" this way, but not me. besides, how many new replacement options are made here in the USA? I think NONE.
Edited by dodge trucker, February 06, 2016 - 04:12 PM.
Posted February 06, 2016 - 06:28 PM
Posted February 06, 2016 - 06:31 PM
Edited by coinman66, February 06, 2016 - 06:33 PM.
Posted February 06, 2016 - 07:20 PM
Cam followers should turn easy. Valves might turn, but be little tougher with spring pressure on them. Mind the spring and keeper might turn too, and not the actual valve. I see in very first picture the problem is the points cover is Missing! Ha! Run a wire down that hole in valve compartment to make sure it is letting oil leak back down in case and not plugged. New gaskets on the cover too, should be a small kit to get from lawn-mower shops for that. Might have the new mesh in kit even? Don't overtighten that small holding nut, might strip or snap off. I agree with the Marvel Mystery Oil in the gas and oil for awhile to see if rings might loosen up or some other odd thing. BUT, most likely the engine is just getting worn out and needs some work done to it. Good Luck! And, use straight 30 wt, not the 10-30 oils, they seem to burn off easier.
Posted February 06, 2016 - 07:34 PM
How much does it smoke?
Any smoke out the exhaust?
Does the motor have knock?
If it doesn't use much oil and doesn't have a knock, live with it, wait for it to get worse.
Any blow by the engine has is gonna come out the breather vent.
Posted February 06, 2016 - 07:46 PM
did you set the valve gap by the manual?
if you do not have a manual, you can download one from Kohler.