Help with timing.

[jeffscub]

Originally Posted by Matt G.

ccr147-

There is no 'ST' or 'DC' marks...there will be a 'T' for top dead center, and 'S' or 'SP' for spark point. You use the 'S' or 'SP' mark to time the engine.

Here's another thing...if you are using a cheap digital multimeter, the meter's sample rate is extremely low, so you'll need to turn the flywheel VERY slowly or you'll miss the mark and have it timed wrong. The older analog types actually work better, as the needle fluctuates almost immediately.

jeffscub-

'dial industry'...you mean 'dial indicator'? If you set them as they were starting to close, with a dial indicator, and the engine runs, there is something really messed up with your engine. That doesn't make any sense at all. The points will create a spark when they open, not close.

yes, i meant to write dial indicator, (i have a new phone). the points were gapped at the point where the rod was at the fartherest distance out of the motor. sorry for the typo. and i should have read my notes better before opening my mouth about where i gapped the points. i apologize. jeff

[jsoluna]

I assumed it was a timing mark I wasn't familiar with, but the original post made sense - a mark for the timing, a mark for TDC.

I wonder...what is commonly wrong in these engines that is causing this discrepancy? Maybe it is that push rod, I'll look into that as well.

And maybe an analog voltmeter works better, but I've not had a problem getting the points to open dead on with the S mark using my decent DVOM. My engine just doesn't want it set there. I hear knocking, see excess exhaust fumes and know it isn't right, no matter what it "should" be. I'm happy, Cub's happy. It's not that I doubt that Matt's method is correct, I just know that in my particular application it doesn't fly.

Valve adjustment did fix the slight miss after warmup, though - I should note that. Intake was too tight by several thousandths, exhaust was too tight by just a hair. Feels like all I do is fix previous owner's "fixes"....

So yeah, I'd check valve clearances too - after breaking in the engine it'd be a good idea anyway.

[ccr147]

So I pulled the motor and checked the keyway and the valves. Key was fine, the intake valve was about .002 to tight. Still didn't fix the issue. The flywheel definatly has a dc mark and an st which could be sp its a little worn. Anyways it'll only run on the dc mark. It runs better but not perfect. So it still drops in rpm and stalls if u put a load on the engine and hunts when u try to rev it back up so I thought ill reset the governor. Loosened the bolt start to turn the shaft and snap! I could hear something fall down to the oil pan. Not good.

Is this going to be a big pain to replace the gear and cross shaft?

Curt

[_DX3_]

Originally Posted by ccr147

So I pulled the motor and checked the keyway and the valves. Key was fine, the intake valve was about .002 to tight. Still didn't fix the issue. The flywheel definatly has a dc mark and an st which could be sp its a little worn. Anyways it'll only run on the dc mark. It runs better but not perfect. So it still drops in rpm and stalls if u put a load on the engine and hunts when u try to rev it back up so I thought ill reset the governor. Loosened the bolt start to turn the shaft and snap! I could hear something fall down to the oil pan. Not good.

Is this going to be a big pain to replace the gear and cross shaft?

Curt

Sounds like the cross shaft tab broke off. Better that it did this now then when the motor was running and break the rod.

The Cross Shaft and governor gear are the "first" things to be put into a motor and the last things to come out due to their location. It's not a really bad job to break the engine down to get to them tho. If you get in that far, I would replace the governor gear, and put a new cross shaft and cross shaft bushing back in.

Download the Kohler service manual located in the Tractor Technical library. It will show you how to disassemble the motor and the governor gear location.

Here is a pic of my 12hp motor with the new gear installed.

[Rhoderman]

Ouch. I'm got a K301 sitting in the shed with that very problem (cross shaft tab). Since that was the first part I put in when I rebuilt my current K301, I figured it would just become a "buildable block". The rest is in really good shape I think.

On the timing issue, I have a set of points that just won't work with my engine. I think they might be Chevy points. They just won't open far enough IIRC. Bought from someone I will never buy parts from again.

[ccr147]

Yeah this really ticked me off, I don't even have 30 hours on the engine yet. Hopefully she'll come apart and go back together again quickly. I'd like to get it done this weekend, but we'll see. I wish I had the time to engineer an electronic adjustable rev limiter for the engine. I really like the pointslayer electronic ignition module I put on it sure would be nice to expand upon that.