C engine lacks power

[Scott Todd]

Got a C where the engine has enough power to propel the tractor or run the mower deck but not both. I had it hauled to a repair shop but it seemed to work OK for them, and when they hauled it back it seemed to work OK for a day or two, but after sitting several days and attempting to use it again the problem was back. I lose nearly 200 RPM just engaging the mower deck.

I seem to remember an earlier thread about spark advance weights getting sticky but don't know how to get at them. Seems like the vibration and bumping around of being transported might have temporarily shaken them loose. Does that sound like a possibility? This is a pre-war C that's been modified to a coil type ignition system, but I doubt they used an AC distributor. Someone recognized the points as being IH brand when I replaced them a year ago so it wouldn't surprise me if that's also the brand of the distributor.

One other question- the engine tops out around 1400 RPM under no load and I think the manual said it's good to 1600. I've got the throttle rod set as far forward as it can go and manually moving the arm on the side of the carburetor I can get the needed extra speed. I just can't find any other adjustments to give me that extra 200 RPM for actual field work. Where would it/they be?

Scott Todd

 

[BushogPapa]

For now, I would not worry about that upper 200 RPM..

Do the Governors kick in and hold the RPM's when under load...until the engine cannot keep them up.??
If they do, they are working ok..

You do know that, in order for a governor to "work", it needs to "see the load", to react to it and that means it will allow a certain amount of drop in RPM, relative to the Load..
Hope you find the problem..it could be many things, right now..
Ron.

 

[teddy52food]

Put a new spring in the gov. for those extra RPM's.

 

[Dick L]

The advance weights under the points when froze/rusted it normally will not pull a load. Having a top RPM of 1400 would not normally be from the advance. If it was and you reached behind the carb and pushed the throttle rod to make it run faster it would not run faster. It would tend to die out. If it being out of adjustment would be causing the lower RPM then when you have the lever to wide open the pivot lever on the top of the governor would be as far as it could go. You can push the lever to wide open and see it you can move the lever on top of the governor farther. If you can"t you are out of adjustment. If you can you are most likely in need of a stronger spring on that lever.
All of this can be checked in a very few minutes.

 

[Scott Todd]

@Dick- yes, the lever atop the governor still has a small bit of travel left when the throttle rod is on full speed. I felt the governor pushing back when I pushed on it.

@Ron- Just driving the tractor around the RPMs seem fairly stable unless I hit a good incline. Not sure how I'd know how well the governor is acting beyond that.

 

[Dick L]

I would now find a timing light and check the timing.

To make power you need compression, Hot spark at the right/correct time and fuel. You need power ability from the above to cause the governor keep from dropping RPM's under load.

If you can make it run up to about 2000 RPM by hand at the carburetor then it most likely is not fuel. If you have good compression and a good spark it drops back to making sure the hot spark occurs at the correct time or a strong enough spring to over come the spinning governor weights.

You need the fire line in the inspection hole using a timing light when checking for the correct time. When timing by ear fails just go for the light. It don't lie.