Kohler K341 rebuild.

[WheelhorseBob 1,550]

I posted in the restoration page regarding a disassembled K341 I picked up. I was told it came out of a C165. Anyway, after It was disassembled the owner, an elderly gent evidently lost interest. He kept records and owned it from new. Seems it threw a rod in 2009 and he put a new or refurbished crank, new rod and std. piston. His brother who I bought it from said it still burned oil so he bought a C145 which he still has. Last night I put all of the puzzle pieces together to understand what I got myself into. I pulled the piston and rod out. The crank looks perfect and the rod is as new. The piston is new but I soon discovered why it burns oil, the top ring was never gapped and was tight. The cylinder has a decent ridge although no scores. I don’t have all measurements yet but he sent a new .010 over piston with it so I assume he figured out where he went wrong years ago. I’m going to completely strip the block and bring to a local machine shop for boring. I also got new valves with it so I’ll most likely replace those. The only thing I know I’ll need are lifters, he left them unoiled in a cardboard box and they are a bit rusty. I’m sure I’ll have many questions and I’ll post them here. First one, it has the old style balance gears. Leave them or toss them?

[squonk 43,701]

Toss the gears.

 

 

[ebinmaine 72,346]

I'm with @squonk

 

Too many stories although the originals lasted quite a while. 

 

I understand one can purchase a plate of some sort to help balance......?

 

 

[pacer 3,177]

1 hour ago, WheelhorseBob said:

The piston is new but I soon discovered why it burns oil, the top ring was never gapped and was tight.

 

Yeah, the things you can run into when we buy these things - your story of it sitting since '09, and not doing the piston when he had done all the other work, etc.

 

I had a similar story with a D200  ---- young ... kid? (18-19-20yr) had inherited his Wheel Horse loving grandfathers entire shop which was rich in parts & tools. The 200's story was told that he had it 'rebuilt' but it was smoking badly. He had visions of making a ton of money selling all this and was asking $1500  for it, sitting on flats, outside, seat in shreds, etc, etc. After about a month of haggling I finally convinced him that his figures - on everything - was way out of line. I gave him $200 and brought it home and quickly got it running and guess what ---- it smoked like crazy!! On tear down as soon as I popped the first .020 new appearing piston out I saw the problem .... whoever had assembled the rings had stacked the gaps perfectly inline .... on the downside of the opposed twin!! And it obviously HAD been thru as the cylinders were freshly bored. To be on the safe side, I put new pistons/rings in and ----- made SURE to NOT stack the ring gaps! And of course it quit smoking! and ran beautifully - and still does til this day.

 

I'm in the 'ditch the 'grenade' gears' group and from your description of the bore - piston sloppy - I wouldnt count on that .010 piston being enough. might just take more that .010 to clean it up. Oh, and dont forget to line your ring gaps in a nice row.....

[WheelhorseBob 1,550]

21 minutes ago, pacer said:

 

Yeah, the things you can run into when we buy these things - your story of it sitting since '09, and not doing the piston when he had done all the other work, etc.

 

I had a similar story with a D200  ---- young ... kid? (18-19-20yr) had inherited his Wheel Horse loving grandfathers entire shop which was rich in parts & tools. The 200's story was told that he had it 'rebuilt' but it was smoking badly. He had visions of making a ton of money selling all this and was asking $1500  for it, sitting on flats, outside, seat in shreds, etc, etc. After about a month of haggling I finally convinced him that his figures - on everything - was way out of line. I gave him $200 and brought it home and quickly got it running and guess what ---- it smoked like crazy!! On tear down as soon as I popped the first .020 new appearing piston out I saw the problem .... whoever had assembled the rings had stacked the gaps perfectly inline .... on the downside of the opposed twin!! And it obviously HAD been thru as the cylinders were freshly bored. To be on the safe side, I put new pistons/rings in and ----- made SURE to NOT stack the ring gaps! And of course it quit smoking! and ran beautifully - and still does til this day.

 

I'm in the 'ditch the 'grenade' gears' group and from your description of the bore - piston sloppy - I wouldnt count on that .010 piston being enough. might just take more that .010 to clean it up. Oh, and dont forget to line your ring gaps in a nice row.....

I’ve  rebuilt numerous engines hence bringing it to the machine shop for proper measurement. I would agree .010 may be wishful thinking. At least the crank and rod are perfect!

[Maxwell-8 4,367]

2 hours ago, squonk said:

Toss the gears.

 

 

Is that the balance gear???? I thought they where why bigger(heavier). They can't do a lot. 

[squonk 43,701]

Yup

[redone 45]

Guys, I am a rebuilding a 241. I need advice on timing those balance gears. Yes these gears are new. So that's all ok.

I do have the tool to set the timing. But I am not sure about setting the gears inside the block

I 've read instructions off of Kohler web site. But it's not explained well

Thanks

Bill

 

[rjg854 12,151]

1 hour ago, redone said:

 

I 've read instructions off of Kohler web site. But it's not explained well

 

 

@richmondred01  may be able to answer your question

[richmondred01 2,307]

Unless it’s a M16 I would recommend removing the balance gears. 
 

As for wheelhorsebob. Most likely the crank will need to be ground so have your machine shop check that, grind valve seats and also check to valve guides especially the exhaust guide. 
if there’s play replace them now while it’s torn down. 
Just my two cents. 

[WheelhorseBob 1,550]

12 hours ago, richmondred01 said:

Unless it’s a M16 I would recommend removing the balance gears. 
 

As for wheelhorsebob. Most likely the crank will need to be ground so have your machine shop check that, grind valve seats and also check to valve guides especially the exhaust guide. 
if there’s play replace them now while it’s torn down. 
Just my two cents. 

I lucked out with the crank. The previous owner put a brand new one in back in 09. Paid over 200 bucks for it. The rod is as new as well. Came with a new .010 over piston and new valves as well. As previously mentioned IT very well may need more than a .010 bore though. We’ll see. 

[Bill D 2,246]

Leave the balance gears out.  Contact Scott @Greentoredabout balancing the crank or installing one of David Kirk's balance plates for you.  Bill

[ebinmaine 72,346]

23 hours ago, ebinmaine said:

I understand one can purchase a plate of some sort to help balance......?

 

1 hour ago, Bill D said:

or installing one of David Kirk's balance plates for you.  Bill

 

That's the one!!

 

Thanks Bill. 

[Greentored 3,220]

I just went through this on a K341 I swapped into my 1277. There is definitely a noticeable difference when removed, but personally do not think it shakes much more than any other big block Kohler without the gears.

I have been using mine for a good month and dont even notice it anymore.

a single cylinder engine is going to shake no matter what, but having it professionally balanced or installing one of Kirks plates is going to smoothe it out quite a bit.

[WheelhorseBob 1,550]

Engine is at the machine shop. I should know how much the cylinder needs next week. He measured the crank and it is perfect. He said the valve guides were excellent as well. He doubted.010 was gonna do for the cylinder so now I have to think about parts. Let’s just say I hadn’t looked at genuine Kohler parts until today. $$$$$ I thought Onan parts were expensive but Kohler takes the cake! I will be looking at aftermarket so if anyone has had a positive experience with one brand or the other please do share.

[ebinmaine 72,346]

4 minutes ago, WheelhorseBob said:

Engine is at the machine shop. I should know how much the cylinder needs next week. He measured the crank and it is perfect. He said the valve guides were excellent as well. He doubted.010 was gonna do for the cylinder so now I have to think about parts. Let’s just say I hadn’t looked at genuine Kohler parts until today. $$$$$ I thought Onan parts were expensive but Kohler takes the cake! I will be looking at aftermarket so if anyone has had a positive experience with one brand or the other please do share.

@richmondred01

[WheelhorseBob 1,550]

On 5/24/2021 at 9:52 AM, Greentored said:

I just went through this on a K341 I swapped into my 1277. There is definitely a noticeable difference when removed, but personally do not think it shakes much more than any other big block Kohler without the gears.

I have been using mine for a good month and dont even notice it anymore.

a single cylinder engine is going to shake no matter what, but having it professionally balanced or installing one of Kirks plates is going to smoothe it out quite a bit.

Did you install one of Kirks plates? Seems like a good idea. In your rebuild did you go oem on parts or quality aftermarket? I’ve been horrified by some of the prices I’m seeing. Kohler stock rod @145.00 and piston with rings .030 @ 250.00!  400.00 for a cast rod and piston, Ridiculous!

[Greentored 3,220]

On 5/29/2021 at 10:00 AM, WheelhorseBob said:

Did you install one of Kirks plates? Seems like a good idea. In your rebuild did you go oem on parts or quality aftermarket? I’ve been horrified by some of the prices I’m seeing. Kohler stock rod @145.00 and piston with rings .030 @ 250.00!  400.00 for a cast rod and piston, Ridiculous!

I balance automotive assemblies as a side job, so was fortunate to have the setup to weigh and drill the counterweights and press tungsten in to do it.

The original stock rod and crank were perfect and got reused, and went with a Stens piston and rings.  Was very happy with the quality.

Lot of guys are buying the cheap aftermarket kits and they appear to be holding up just fine.

Maybe someone else will chime in on that.....

[WheelhorseBob 1,550]

Thanks for the insight. I’ll go aftermarket. Hell I could rebuild it 3 times over for the cost of oem. And that is unfortunate.

[richmondred01 2,307]

11 hours ago, WheelhorseBob said:

Thanks for the insight. I’ll go aftermarket. Hell I could rebuild it 3 times over for the cost of oem. And that is unfortunate.

not all aftermarket parts are created equal. One has to be very careful and mic every part prior to machine work being done.

I have had customers provide me “kits” that they bought from “reputable” companies.  Out of the box they were as much as 005 off.

I don’t want to be sued so I’m not naming names but many folks use these companies and the parts are terrible.
Just because they are on YouTube, and gives advise, doesn’t mean anything.

 

Edited June 2, 2021 by richmondred01

[WheelhorseBob 1,550]

Telling.