Poor old engine...
 

Man, someone abused this poor old K301 beyond excuse. This is from my 122 I bought from some kid who probably raced it down the street and who knows what.
The ring gaps weren't lined up like this, but the 2nd and the oil ring were lined up when I took it apart.
The 2nd ring is installed upside down.
The top ring has a bit excess clearance, would you agree?
Poor old engine... She's getting lots of new parts now. I'll never abuse her like this I swear.
She sounded like heck, and smoked like no tomorrow, but she still RAN! Kohler.

http://i43.photobucket.com/albums/e3...PistonFAIL.jpg

http://i43.photobucket.com/albums/e3...RingClrnce.jpg

I've got a K241 that probably is similar inside...engine was said to have ran but smoked bad. I took the head off and found the piston is worn close to 3/16" smaller than the bore....I think it'll be fun to see what it looks like when I take it apart.

yea, me too! little 71 cubby's little heart just gave out. maybe i over worked hims, but it did smoke to begin with. got another k161 on bench, federal yellow in on monday. need to remove pto and crank pully and put on new k161. the 71's k161 just free spinns. but will have it repaired at a later date. at least i can have everything fixed on these good-'ole IH cubcadets!:American Flag 1:

The amazing part (to me) was that the bore cleaned up at .010 over!
The piston had about 1/8" of "rock" to it.

the k161 on your left{no head} is out of my 72, which is being re-painted and will take over snow duty by next snow. this motor is almost ready for paint.31$ a quart of federal yellow. on the right, is my 71 k161, which the crank free-spinns. will have 71 k161 repaired sooner than later. untill then, going to run the 71 k161. i dont believe anything major happend, other than a broken connecting rod and replace the piston and rings. going to pull the pto and starter pully and put on the 72. will not having a pto cause the motor to become out of balance? no need for one on the 72 snow pusher motor. well, its my fun and dont mind all the extra wrenching. wondering how much $ in replacement parts will cost. hummm...:BB&YS:

here is what happend to 71 k161. the connecting rod snapped in two, and gave out around the crank. this next picture shows the crank pin with minimal scuffs/grooves. guess i need to check w/ micrometer for out -of-round [1.1855 to 1.1860 new] hope i dont need to take out and have ground .010 undersize. so hopefully its only c.rod, rings, and oilbase gasket. the piston and block show no damage at all so far. says here i need to check piston ring grooves and land. i some-what understand. i sure do hate taking something like this to somebody to be fixed. thats not in my program. i could use some feed back, i've never had a job like this. but iam not with out a prayer, as i can simply turn to my 72 k161 and worrie about the 71k161 a bit later. the show must go on.:American Flag 1:

I think that crank needs to come out and have the aluminum cleaned off of it at a minimum. Run your fingernail along the axis of the crankpin...if it catches anything, you've got to clean it off.

The crank will need to be rmoved from the block. I doubt you will have enough clearance to check crank jounal with the crank in the block.

While the motor is apart I would check the cylinder bore in 6 places as Kohler manual recomends. Odds are you will find a taper in the bore and the bore will be out of spec. By time you hone the cylinder bore it will be out of spec. If the piston shows any signs of being burnt above the top ring groove it should be replace.

I had a gent who thought he could get by honing and new rings. Two years later I had to rebuild the motor because it was using oil and down on power.

Best thing you can do is spend the money now and do the job right the first time.

thanks guys! that is the best advice and i will do just that and have the job done right the first time! will keep ya all posted on the 71 k161!:beerchug:

Did anyone else notice?
 

Johncub7172
When I saw the first pictures you sent, it sure looks like you have the engine sitting on the coffee table in front of the couch. Or else your shop is a heck of a lot fancier than mine.
So I figured maybe it's just cold out in your shop and you brought the engine in the house for the picture.
Then in the second set of pictures, with the engine apart and oil on the cardboard underneath it, I can see that same pattern from the couch in the background.
So, my question is: How in the heck do you get away with working inside, dismantling an engine on the furniture? If I tried that my wife would give me such a shot, :bash: right upside my head.

looking more carefully, its eazy to see that the piston is damaged.

the old head gasket on left, new carbon gasket on right. looks like the old ones were made pretty well. the carbon worked good.

yes i do, and prep'in for paint starting this tuesday. i'am hot married yet, so i have my own home. paint job might turn out good.

I would consider replacing the governor gear (if it is a plastic gear) while you have the motor apart. The gears get brittle with age.....trying to save some aggervation down the road.

Is that new gasket aftermarket? The reason I ask is because the Kohler gaskets have a "fire ring" like the old one on the left in your picture. Most aftermarket gaskets don't have that, and I don't think they work as well. It's difficult enough trying to keep head gaskets from blowing on these because the head and block are different materials, so it needs all the help it can get. Kohler's gasket is best...I would get an OEM gasket with the fire ring.

the bag on the left was what the new head gasket came in. it is totaly identical to the gasket on the right in the last picture,which came in the bag on the right in this picture. looking at the old head gasket, is why i replaced it for the new one. my local cc.dealer said that they dont make the old style anymore. they are carbon fiber now and are rather soft, as i was told by him not to bend it. both part numbers are the same [41 041 10-s] for the k161. i ran the gasket all summer and no leaks were seen again. when i built my 383 stroker, it was recomended that i use a carbon fiber head gasket when useing aluminum heads on an iron block, but cost more than the copper that i went with. as far as i can tell, yes, now they are Kohler Genuine Parts.i have no idea why my old gasket leaked, it realy does look good.

your advice is wonderful. left pict. shows a steel gov.gear! next shows a clean and inspected inside components.

Oops...I forgot we're talking about a K161:bash2: I think the only gasket you can get for those is the kind without the fire ring. Never mind then...

here is a picture of the 71 k161 all put back togeather. was thinking a bit about what the heck happend here. i'll admit, i was running her hot and hard. after a bit, we started to loose power, had to use 1st. gear to get it in the shop. on our way up the drive, a flame appeared out from the muffler, then came the knocking. i shut it off right there. about a hour or so, i started it up and the knocking was still there but no flame this time. and just that quick, she went silent, only the s/g on and running. so there was very minimal time from the power loss, to the flame, to the knock. now i know the crank is super strong v.s the piston and connecting rod. no bearings in the c.rod, as made. guess the rings went, then the piston. looking at the picts. i've all ready posted, its funny to me how that c.rod buckeld and the big scuff on the piston. so my question is: would it be possible at all for the crank not to be damaged too bad, given the time it all went down, the big difference in the two materials. if i can get an "out of round " reading of the journal with out removing from block, having the cyclender honed and new hardware, i would be in good shape. but i never broke stuff like this and dont realy know the very extendent of damage caused by. i'll clean with emery cloth and go from there.:beatdeadhorse:

Engine
 

It has been my experience over the past 50 years is that the scuffing above the top ring is caused by heat build up,
carbon deposits, and wear.
Combustion temperatures get high, add some carbon, and the aluminum piston is near the melting point.
so it tends to gall the piston to the wall at the top of the bore.
By design, the piston is slightly smaller at the top, above the ring, but as the piston wears, and the bore wears farther down, the galling takes place on the piston as it rocks in the bore when it is at top dead center.
On repairing the crank journal:
I have used a flat file to CAREFULLY remove the aluminum that is galled on the journal, successfully many times.
but it has to be done carefully so you are only removing the alum, not iron journal .
if you use emery cloth you will remove both, --not good
another trick is to use acid, it will eat the alum. but not the iron journal ( wish I could remember the name of the acid) but they use it to clean alum. wheels. ( sulfuric acid works also)
acid takes a little longer to do, as I dab it on and go do something else, checking back periodically.
---the acid works well on cylinder walls to remove galled alum. in 2 stroke applications.

On the head Gskt:
They usually blow right above the exhaust valve as that is where the most heat is.
check your head for flatness, and if need, surface it and proper torque is very important on those engines, retorquing several times after it has been run @ operating temp.

Muriatic acid (Hydrochloric acid to chemists) works great to clean off the aluminum. I'll have to find a small writeup I did of this.

The motor is in need of a rebuild.
There are 2 different ways: cheap way or the right way.

Odds are the crank will have grooves/gouges in the crank journal. You may be able to measure the crank journal. I wouldn't want to risk the muriatic acid getting on anything but the crank journal. Cleaning the crank journal with emery cloth will leave fine particles left in the inside of the motor. Unless I misread your post you want to hone the cylinder with the crank in the block. That is a big no-no in my book. The metal fines from honing will need to be removed from the block. Only way to do that is to take the motor apart. I rinse any block that I'm rebuilding and them wash the block out with soap and water. If the metal fines get in the bearing the motor will have to come apart again and the bearing needs replace. Plan on spending $25 to $40 for a bearing. Seals get brittle with age....when this happens the motor will leak oil.

The valves and bearings are removed before honing or boring the cylinder wall. This is a good time to check and grind the valves if needed. I will check the cylinder head and the top of the block for flatness. A machine shop can true the head and block if they are not flat.

I've know some who tried to fix crank in the motor or hone the cylinder with the crank in the motor. Yes they save a few $$$ this time. 2 to 3 years from now they usually have to spend more money to rebuild the motor the right way.