803a won't hold frequency under load

[mijoe]

Good Evening All, I was working on a new-to-me 803, and I noticed the unit's engine speed varies with even a light load. The largest swing I saw was between 58.5hz and 61. The engine speed varies every 5 second or so, in a smooth, cyclical way. So far on this unit, I have changed the oil, coolant, well nut, fuel and filters. When this is going on, the temp and oil pressure look fine. Where should I look next?

 

[nextalcupfan]

How much load will the unit take before bogging?
And how much load is it under when this was happening?

 

[mijoe]

How much load will the unit take before bogging?
And how much load is it under when this was happening?

It started doing it when the engine was up to temp, at 75% indicated load. After that, when started and already warm, it would start to behave the same with as little as 20% load. When the machine is first started, it runs fine, even if it's already warm. As soon as load is applied, the engine speed starts hunting.

 

[Ray70]

If it's hunting up and down rather than just bogging down I would tend to suspect the governor droop is set too sensitive.
Check the TM, the drop screw ( allen head screw ) is located under the 3/8" pipe plug in the timing cover, just forward of the throttle lever. The TM explains how to adjust it.

 

[kloppk]

Ray70
That was my hunch too.

 

[mijoe]

...The TM explains how to adjust it.

This sounds like the likely culprit, and I found the governor adjustments, removal, installation on page 3-40, but I have not yet found a section about adjusting the droop. I'll keep looking for other manuals. Thanks for the pointer

 

[Guyfang]

You are probaly looking in the wrong TM. The Drop adjust procedure is in TM9-6115-642-24. PDF reader page # 209, Paragraph 4-7. You would think it would be in the TM9-2815-253-24. But for some reason its not.

 

[mijoe]

Thanks Guyfang, I was looking at the wrong TM indeed. I'll give this a shot.

 

[Light in the Dark]

A timely thread... got an 802 that's doing a bit of a frequency dance this morning. Thanks for the direct TM location info.

 

[mijoe]

A huge thanks to Ray70, kloppk and Guyfang! It is astounding what a 1/2 counter-clockwise turn can do. This machine runs like a top now, thanks to your assistance. Thanks again

 

[Guyfang]

You did the work partner. Sometimes we all need a pointer.