No compression, maybe broken connecting rod

[John2189 454]

5 hours ago, squonk said:

Everyone who would run this block, raise their hand! 

 

 

 

 

5 hours ago, squonk said:

Everyone who would run this block, raise their hand! 

 

 

 

 I would break it off the rest of the way, if it is not close to where the rings would hit it and no other cracks in the cylinder wall. I would run it. 
john 

[Gregor 4,846]

Unfortunately, I don't believe you can see the piston on a Kohler, simply by removing the plug. On a small block, it is possible to check with a Tecky timing tool.  It won't work on a big block, the tab will not reach the piston. I bought on of these from the Jungle Book.

For $80, it shows a remarkably clear picture. It could show you what's in the pan, but of course to will not show you the extent of the damage. The endoscope is a very handy tool for a lot of things. I use mine on a regular basis.

I can't wait to see pics of the inside of this engine.

[Gregor 4,846]

34 minutes ago, John2189 said:

 

 I would break it off the rest of the way, if it is not close to where the rings would hit it and no other cracks in the cylinder wall. I would run it. 
john 

I would remove the broken piece. If my machine shop told me there was no further damage, and no cracks, I would run it also.

[68 raider 12 3]

I had an old timer in my town dissect the engine and it's confirmed the connecting rod snapped and the crank is a little busted up, the cylinder walk is surprisingly still in good condition no crack, scratch, or chips. Only problem is I'm having a hard time finding a replacement crankshaft for the Kohler k301s engine model. Anyone have one or know where to find one?

[Gregor 4,846]

17 minutes ago, 68 raider 12 said:

 Anyone have one or know where to find one?

Personally, I would not invest any money in this engine, until the block is checked by a machine shop. Cracks are not always visible with out a magna flux test. If it turns out OK, you may be able to find a used short block on Facebook, but then again, you never know what you are buying. May ne be any better than what you have.

[68 raider 12 3]

The guy I had look at it has been working on engine his whole life, he told me it doesn't necessarily need a new crank but he wants to replace it while he's got the engine tore apart. I get he's not a machine shop specialist but I trust him.

[squonk 41,155]

2 hours ago, 68 raider 12 said:

I had an old timer in my town dissect the engine and it's confirmed the connecting rod snapped and the crank is a little busted up, the cylinder walk is surprisingly still in good condition no crack, scratch, or chips. Only problem is I'm having a hard time finding a replacement crankshaft for the Kohler k301s engine model. Anyone have one or know where to find one?

I think I may have a 301 crank here.It will probably need turning

[68 raider 12 3]

4 hours ago, squonk said:

I think I may have a 301 crank here.It will probably need turning

What do you mean by turning??

 

[squonk 41,155]

48 minutes ago, 68 raider 12 said:

What do you mean by turning??

 

The crank came out of an engine with a broken rod. It had some aluminum melted on to the journal. I polished it but it may be out of round and need to be turned .010" undersize by a machine shop.

[68 raider 12 3]

On 7/18/2021 at 1:45 PM, squonk said:

I think I may have a 301 crank here.It will probably need turning

Do you have a picture of it??

[squonk 41,155]

5 hours ago, 68 raider 12 said:

Do you have a picture of it??

Actually it belongs to a friend of mine who had the blown engine. i thought I had it here but he must have it. I'll get it tomorrow.

Edited July 23, 2021 by squonk

[squonk 41,155]

Crankpin is out of round and depending on the accuracy of my old micrometer the crank cannot be turned down any more to use with an undersized rod. It would have to be built back up and re-machined or a rod machined for bearing inserts.

 

You can read about this here:http://gardentractorpullingtips.com/engine.htm

 

 

Edited July 24, 2021 by squonk

[WheelHorse520H 708]

On 7/24/2021 at 12:48 PM, squonk said:

It would have to be built back up and re-machined or a rod machined for bearing inserts.

Just tuning in here for the education, how do you build it back up?

Andrew

[Jeff-C175 7,202]

26 minutes ago, WheelHorse520H said:

Just tuning in here for the education, how do you build it back up?

Andrew

 

I had it done to an MG crankshaft a long time ago.  The machinist builds the missing metal back up by welding and then re-machines it back to spec.

 

I saw a YouTube video a while back where the guy used a 'spray welding' technique to repair a blower wheel journal but I don't know if that could be used for repairing a crank.

Edited July 30, 2021 by Jeff-C175

[WheelHorse520H 708]

10 hours ago, Jeff-C175 said:

The machinist builds the missing metal back up by welding and then re-machines it back to spec.

 

That’s what I was guessing, that’s the only way I know to build metal up that will withstand the forces of an engine.

[richmondred01 2,237]

A sleeve can be used to repair the chipped or cracked cylinder apron.

The machine work and sleeve costs 150.00. 
Worth the cost for the k341.

 

[Gregor 4,846]

On 7/13/2021 at 7:58 AM, squonk said:

The crank will most likely be torn up where the rod used to be connected to it.

 

 

That looks an awful lot like my MV-16.

[richmondred01 2,237]

95% of the engines I get with broken rods the crank looks like that. They generally clean up fine at .010 or .020.

40% of the engines I get that rods have broken have the chipped apron skirt. I’ve got several core blocks so I use them or put a sleeve in. 
 

[squonk 41,155]

5 hours ago, richmondred01 said:

95% of the engines I get with broken rods the crank looks like that. They generally clean up fine at .010 or .020.

40% of the engines I get that rods have broken have the chipped apron skirt. I’ve got several core blocks so I use them or put a sleeve in. 
 

Can you get .020" rods Mark?

[richmondred01 2,237]

I have .020 rods for 10hp through 16hp.

I can’t get them any more for 8hp down. 

[richmondred01 2,237]

Here’s a sleeve. Of course it takes it back to standard size.

[Gregor 4,846]

12 minutes ago, richmondred01 said:

I have .020 rods for 10hp through 16hp.

I can’t get them any more for 8hp down. 

Do you have anything at all for an MV-16S, spec # 56506

[richmondred01 2,237]

6 minutes ago, Gregor said:

Do you have anything at all for an MV-16S, spec # 56506

I don’t but I will PM you where you can get them. 

[richmondred01 2,237]

Before and after.

I’m able the get most of them cleaned up.

[Gregor 4,846]

OK   Mines not THAT bad.