I guess im going back into my M12S

[RED-Z06 2,120]

The backstory.  312-8 had been sitting in a swampy field about 16 years, guy told me i could have the 48" blade if i took the tractor.  I got it running after unseizing it, ran good but ran too fast, no governor response.  Broke it down and the governor had lost a flyweight.  I bare blocked it, new rings, honed the pitted cylinder, hot tanked the block and replaced the governor gear.  Back together it ran great, good governor response..but it started smoking and rattling.  I tore it back apart..rings were toasted...likely missed some grit from honing.  But, i couldn't find the source of the rattling..the crank mic'd out well within spec, rod was in spec, bore was almost new size, piston looked fine but looser side of spec at the skirt.  I replaced the rod, piston, rings...and immediately on start up..it rattled.  But, only under load.  Since then ive put over 100hrs on it pushing asphalt miings and dirt..and its been great, oil never has any metal in it, never uses any oil.  But today, the noise its made, got abruptly worse.

 

My guess is, balance gears...i still feel like if it was a rod it would have chucked it by now, or gradually gotten worse, not been consistently the same then suddenly worse.  Its getting cooler here, only into the low 80s today🫠

 

https://youtu.be/tuv_uOhyynY?si=-uZiWt65PaLk28cH

 

[Pullstart 59,736]

Glad you caught it before a hole in the block told you there’s a problem!

[RED-Z06 2,120]

35 minutes ago, Pullstart said:

Glad you caught it before a hole in the block told you there’s a problem!

 

Ive been waiting for the block to window out for almost 2 years...in March i had about 18yds of asphalt millings delivered and i had that M12 at 100% governor turning 3600/3700 rpms for a few hours off and on...figured the trans or engine would break, but neither did.

[ri702bill 7,341]

30 minutes ago, RED-Z06 said:

 

Ive been waiting for the block to window out for almost 2 years...in March i had about 18yds of asphalt millings delivered and i had that M12 at 100% governor turning 3600/3700 rpms for a few hours off and on...figured the trans or engine would break, but neither did.

And that there folks attests to the true Wheel Horse quality.......

[RED-Z06 2,120]

27 minutes ago, ri702bill said:

And that there folks attests to the true Wheel Horse quality.......

Got to give that unidrive credit, on loaded 24x12x12 lugs and 225lbs of operator, it clawed its way through 

[953 nut 51,736]

3 hours ago, RED-Z06 said:

My guess is, balance gears.

            Why didn't you get rid of them while it was apart before?

[RED-Z06 2,120]

6 minutes ago, 953 nut said:

            Why didn't you get rid of them while it was apart before?

Every deleted K series ive used shook bad enough for me to gamble on keeping them.  At this point in time, im going to try and split them off, im not pulling the cam back out.  I dont have the open bench space like i did 2 years ago..and even less patience 🤣

[ebinmaine 63,179]

2 hours ago, RED-Z06 said:

Got to give that unidrive credit, on loaded 24x12x12 lugs and 225lbs of operator, it clawed its way through 

 

That's a lightweight compared to my own setup. 

 

These rigs are rugged.  

 

 

1 hour ago, 953 nut said:

            Why didn't you get rid of them while it was apart before?

 

1 hour ago, RED-Z06 said:

1 hour ago, 953 nut said:

            Why didn't you get rid of them while it was apart before?

Every deleted K series ive used shook bad enough for me to gamble on keeping them. 

 

I've only got two. 

One with the balance gears.  

One without. 

The vibration is... Different... But I do not believe it's more severe.  

Different RPM perhaps.  

 

I'd be interested to see what your engine reveals. 

 

 

[RED-Z06 2,120]

4 minutes ago, ebinmaine said:

 

That's a lightweight compared to my own setup. 

 

These rigs are rugged.  

 

 

 

 

I've only got two. 

One with the balance gears.  

One without. 

The vibration is... Different... But I do not believe it's more severe.  

Different RPM perhaps.  

 

I'd be interested to see what your engine reveals. 

 

 

I had a deleted Cub 1200, it was on AV mounts, it shook the sheetmetal off the engine, muffler, tractor.  It was like like a resonant hum at full throttle.  Had, i think it was a 16Auto, was deleted, it wasn't as bad...but definitely worse than balanced.  Some balanced units shook badly too.  I think Kohler cranks were poorly balanced to begin with.

[oliver2-44 8,852]

2 hours ago, RED-Z06 said:

  At this point in time, im going to try and split them off, im not pulling the cam back out.  

I've had good success splitting them off. A sharp chisel and a good rap and they were gone.

[RED-Z06 2,120]

22 minutes ago, oliver2-44 said:

I've had good success splitting them off. A sharp chisel and a good rap and they were gone.

Thats probably where im heading 

[RED-Z06 2,120]

15 minutes and the engine is out, sump off...no felt rod play, but i found the balance gears are going, and despite the set screws being tight..the drive pulley is loose. It still made the rattle with the pulley removed last time..its possible the sudden increase was the pulley this time.  Regardless...the gears are getting evicted

 

 

https://youtube.com/shorts/zXl9iNDh9QM?si=HpfmBE8RNwTUzLeM

 

 

[RED-Z06 2,120]

Balance gears are gone...fishing out the bits, then back together.

[leabassett@sbcglobal.net 114]

I took the balance gears out of the 14 hp I put in my 140 JD and it runs fine.

[kpinnc 10,746]

1 hour ago, RED-Z06 said:

Regardless...the gears are getting evicted

 

On a 12hp, the shakes should be minimal. 

 

If the pulley is loose, I'd definitely mic the shaft to make sure it isn't whats worn. 

[RED-Z06 2,120]

New key in the crank and cranked the screws down...good and snug.  The cam gear slop has me concerned, that's a ton of lash.  But its back together, backfired on first start and turned the rusty old muffler inside out.  Runs good, still has a bit of noise..i did pull the rod cap and there was no scoring or signs of wear on the new rod.  Not sure at this point, tractor is pretty much trash, both shifters are rotted away at the base, the diff oozes, its very rusty.

 

Ill say this, the shaking is pretty uncomfortable, at idle its bad, at 3600 it makes all the sheetmetal buzzzz...mid range its not bad.  

[pfrederi 17,147]

6 minutes ago, RED-Z06 said:

New key in the crank and cranked the screws down...good and snug.  The cam gear slop has me concerned, that's a ton of lash.  But its back together, backfired on first start and turned the rusty old muffler inside out.  Runs good, still has a bit of noise..i did pull the rod cap and there was no scoring or signs of wear on the new rod.  Not sure at this point, tractor is pretty much trash, both shifters are rotted away at the base, the diff oozes, its very rusty.

 

Ill say this, the shaking is pretty uncomfortable, at idle its bad, at 3600 it makes all the sheetmetal buzzzz...mid range its not bad.  

 

 

That was my result on  K341 after an overhaul and leaving out balance gears.. it is uncomfortable especially when you are running for several hours mowing.  She is going to be on snow blower duty,.. Future over hauls will get new balance gear bearing and take a chance..after all the originals had hundreds in not a thousand or more hours before they grenaded.  Yes l know there is some add on thing to balance it but you have to have the crank machined to accept it.  Not opening her up again...

[ebinmaine 63,179]

12 hours ago, RED-Z06 said:

at 3600 it makes all the sheetmetal buzzzz...mid range its not bad.  

Try running around 3200, 3300.  

That's adequate for daily usage and where my Automatic Tractor seems happy.