129 low power at full throttle

[wh cc guy]

Make sure the exhaust system is not stopped up and is free flowing.

 

[Eric Wittersheim]

dkirk,
I took my tach off of my 1250 and the readings I'm getting seem to be way off, so I was going to try it again later.

 

[Eric Wittersheim]

wh cc guy,

I bought a new muffler, I could put the old one back on. It was a bit loud so I bought the new one hoping it would quiet it down a bit.

 

[Eric Wittersheim]

I have a head gasket on order, should be here tomorrow. But in the meantime I checked the head bolts and most were less than 30 psi. I tightened them up but didn't notice a change in power.

 

[Tc Crawford]

Not sure of the torque but 30 sounds about right for most small engine heads. Could be wrong. But it 21 foot pounds on a lot of them. 30 inch pounds would be low.

 

[HKCooper44]

30 ft. lbs. is the recommended head torque. Sounds like you might have a governor issue. I've had this problem several times in the past, and I did the following: Start the engine, open the throttle wide open. With your finger, move the governor arm forward (counter clockwise). Does the engine speed up, and actually over rev? If not, shut down the engine and be sure the governor spring is in the 3rd hole from the bottom. Loosen the governor arm on the shaft. With small vise grips, turn the government shaft counter clockwise until it stops. Move the governor arm counter clockwise until the throttle plate is wide open, then tighten the arm to the shaft. Start the engine and open the throttle fully? Is the throttle plate wide open? Does the engine now run at full speed? If not, you likely have a fuel feed problem.

 

[Eric Wittersheim]

HKCooper, yes the engine will over rev if I move the governor arm, I have not looked at the throttle plate. I'll take a look at that after work.

 

[lpalma]

Did you check the throttle stop on the governor spring lever? It is to adjust the high rpm , 3650 no load.

 

[Eric Wittersheim]

Yes, the throttle stop is not blocking the movement.

 

[HKCooper44]

It's tough troubleshooting something invisible, but if the governor is properly set, the throttle plate fully opens with the throttle control, and if the points are set right and you have a strong spark, there isn't much left to consider except insufficient fuel. When you load up the engine, has it backfired?

 

[lpalma]

So it goes up to 3600 rpm? A tach like this is what I use..

 

[Eric Wittersheim]

It's tough troubleshooting something invisible, but if the governor is properly set, the throttle plate fully opens with the throttle control, and if the points are set right and you have a strong spark, there isn't much left to consider except insufficient fuel. When you load up the engine, has it backfired?

No, it just bogs down. I looked and the throttle plate is fully open at full throttle. I got the RPM pretty close to 3600 at full throttle without a load but it still bogs. I received my head gasket today so tomorrow I plan on taking a look at the valves. If its the points I am at a loss on adjusting time anymore.

 

[HKCooper44]

No, it just bogs down. I looked and the throttle plate is fully open at full throttle. I got the RPM pretty close to 3600 at full throttle without a load but it still bogs. I received my head gasket today so tomorrow I plan on taking a look at the valves. If its the points I am at a loss on adjusting time anymore.

Still sounds like a fuel issue to me. Anyway, set your spark plug to .030", then adjust your points to .020, which is the only way to set timing. Be sure the negative side of the ignition coil is wired to the points, and give it another go.

 

[mgonitzke]

Still sounds like a fuel issue to me. Anyway, set your spark plug to .030", then adjust your points to .020, which is the only way to set timing. Be sure the negative side of the ignition coil is wired to the points, and give it another go.

He said in a previous post that pulling the choke when it bogs down doesn't help at all, so it is likely not a fuel issue, unless perhaps the gas has gone bad, but usually that causes hard starting.

Plug gap is 0.035" for breaker point ignition per the Kohler owner's manual.

I'll say it again, 0.020" point gap is a starting point. It should get the tractor to run, but it likely does not correspond to proper timing. I had one engine that had to have the points set at 0.008" to get them to break at 20°BTDC.

No, it just bogs down. I looked and the throttle plate is fully open at full throttle. I got the RPM pretty close to 3600 at full throttle without a load but it still bogs. I received my head gasket today so tomorrow I plan on taking a look at the valves. If its the points I am at a loss on adjusting time anymore.

Does the governor linkage look like this, i.e. is the spring in this set of holes?

You are either going to need to figure out how to get the points set correctly or find someone who can. Further troubleshooting is going to be futile if it is not known the timing is correct, as in my experience with these engines, timing is the #1 cause of this issue. Get the timing marks cleaned up and easily visible and use the directions I posted earlier. An analog meter will work better than a digital one since it will react faster to the points opening.

I'll also ask again, have you checked the valve lash?

 

[Eric Wittersheim]

Looks like I had a bad gasket. What's the best way to clean up this mess?

 

[Eric Wittersheim]

I sent that photo and another to a friend of mine that is a small engine mechanic, he said that the cylinder wall is toast. Can these things be bored out with a bigger piston?

 

[mgonitzke]

Yes, 0.010", 0.020", and 0.030" oversize pistons are available. That one is severely eroded. Engine was likely run lean for a long time.

 

[Eric Wittersheim]

Thanks mgonitzke, it never ran right from when I bought it and knew it was running lean so I bought a new Carb, condensor, and points. But I guess I was too late.

 

[HKCooper44]

Still sounds like a fuel issue to me. Anyway, set your spark plug to .030", then adjust your points to .020, which is the only way to set timing. Be sure the negative side of the ignition coil is wired to the points, and give it another go.

Thanks mgonitzke, it never ran right from when I bought it and knew it was running lean so I bought a new Carb, condensor, and points. But I guess I was too late.

I wish I was there to help you, but obviously I'm not. I ran into an issue like this on an abused 1964 Cub Cadet 100. Text me at [email protected].

 

[jack casey]

And replace the gasket which cud be 50+ years old.

Reading these 2 pages of posts finds great mechanics. I'm just a good mechanic. There are no options, the engine has to come out to repair damage....expensive. Looking at this makes me think....scrap. Why not replace it with a rebuilt higher horsepower K engine; as my father would say 'you'll be happier with it in the long run.'
The K241, 301, 321 and 341 are interchangeable, I believe.
Cheers, Jack