1250 Found A New Home

[vr4Legacy]

Originally Posted by jsoluna

I purposely cut that way because I wanted to mow the thick stuff going uphill on that particular pass. In general I wasn't concerned with mowing efficiently, but rather in testing the 1250 thoroughly.

I was thoroughly amazed at how well my 1200 handled the thick stuff.

Glad it's doing well for you!

[jsoluna]

Update time:

The 1250 has been very reliable, but the condition of the engine has only gotten worse. Oil consumption was about 1/2 quart per hour. I enjoyed using the machine so much that I just kept using it and stopped every hour and added oil.

Between fall last year and spring this year I've put about 50 hours on it. Then, suddenly, two weeks ago the Kohler finally had enough. Fuel would not make it to the plug. Had spark, fuel at carb, and some compression. Just died. Even sprayed fuel into the throat of the carb and still the plug stayed dry.

I figured I had a stuck valve, or so much oil soot deposited that the exhaust valve wouldn't seat. I decided to tow it back to the shop and just start looking for an engine to replace it. I have a very hectic and at times chaotic work schedule so a full diagnosis and rebuild isn't in the cards for me this season.

As luck would have it, a forum member who also lives in Ohio said he had a 301 that was a relatively low hour engine that would probably be a good runner. This weekend I hopped in my 87 Samurai and made a couple hour drive to get the engine and some other parts that he graciously threw in on the deal.


Long story short, the 1250 is down but should be back soon. Pictures and such are on the way!

Big thanks to johncub7172 for the donor engine and other QL parts!!!!

[jsoluna]

Well, it's been said over and over again, but these engines can run well enough to mask internals issues for hours and hours.

This is my first time going any further than valve adjustment on a K Series.

I now have two engines for my 1250!

One (referring to this engine as the "replacement") has a chunk missing from the cylinder wall and a matching piece of the piston skirt missing! It also has some portion of the ACR that is loose.

The other is the engine that came in my 1250.
It had valves so covered in oil and carbon that I really am clueless as to how it ran at all. My hunch that the stuck valve was the nail in the coffin was correct. The exhaust valve was pretty sticky, even after the engine had cooled. This block has been bored .010 and has quite a bit of play in the crank bearings.

Both engines ran before being disassembled. My thought was to refresh the replacement engine that didn't smoke or knock. Then I opened it up and found the missing chunks of piston and cylinder.

The original engine would need crank bearings, a rebore, valves, guides, piston, rings, and rod.


I have lots of questions on the possible courses of action. I must also say that dealing with johncub7172 was an absolute pleasure. He went through the trouble of test running this engine for me before I picked it up and then after I tore it apart and found these internal problems he insisted on a full refund. Great guy to deal with.


I'm going to invest in a good micrometer and some telescoping gauges. As of now I only have my mechanical intuition to go off of, and some dial calipers and feeler gauge, which can only get me so far since I haven't tore down one of these engines before.

What do you guys think?

[olds45512]

looks like your first investment needs to be in some lighting.

[jsoluna]

Last shot was just for dramatic effect. It was something that caught the corner of my eye when I had forgotten to turn off the auxiliary overhead bench light. It looked like the holy grail of engines sitting there.

I actually have decent lighting in the shop.

[Ronnie125]

Great thread! I can't wait to get my 1450 up to snuff too. As for the guy you got the replacement engine from, that is awesome that he did what he did!

[jsoluna]

As my time is very limited, I'm thinking about trying to do a quick refresh on the replacement engine.

I'm trying to get some input on whether or not it is worth putting the time into.

The first issue I have questions about is what I am calling the "ACR tab". (I looked at the Kohler Service Manual and did not see a detailed description of this)

This tab is loose. It appears as though it it some sort of guide for the flyweights so when they hinge out they have some support. I can pivot it back over the flyweights (as seen in the second pic) but it is too loose to stay there on its own.

Do I have to remove the cam to try and tighten it back up? I looked in with an inspection mirror and it appears to be an allen head holding it to the cam gear. Maybe not, though. I couldn't get any of my wrenches to grab it.

Thoughts?

[johncub7172]

Thanks J! I would try to help anyone out here! That is amazing how much these engines can withstand abuse!

[jsoluna]

I assume that tab is supposed to remain stationary. It's fixed in place on my original engine by comparison.

[johncub7172]

Originally Posted by jsoluna

I assume that tab is supposed to remain stationary. It's fixed in place on my original engine by comparison.

Would you mind if I posted a link to my k301 I had started for you? Maybe the group would like to see and hear it! Anyhow, off the shelf from sitting at least a decade or more, the k301 fired right up with out problem.

Perhaps, you could have tried to start the k301 before you tore it down to determine engine operation conditions? I think I had the engine in, running, and back out with in an hour.

I know the ACR is a very simple device used to relieve compression slightly upon start up, and thus the weight swings out once started, relieving the tab that actuates the valve on start up. I'm not sure on tolerances to be checked to determine proper functions.

I would not let a broken skirt on my replacement scare you. If its the better of the two, use it! I'm going to lean on my block having the better cylinder measurement, but hey!

Keep up the progress!