D2 governor and pony issues Please read

So how tough can this be.
Obviously the governor ratchet ring is worn and won't hold position. It is possible to rotate the ring to a less worn position but you need to do away with the dowels. The pawl teeth still have to be good enough to hold. I've delt with this issue by a combination of rotating the ring and changing out the linkage pins for bolts to where you can adjust the joint friction to help take some of the load off the worn parts.

That pony sounds like it is worn to the point where you are oil fouling the plugs. If they are Champion plugs get rid of them.
Did you do the side to side plug change to see if the problem follows the plug as was previously suggested?

now Im a bit backwards but before I would go spending big heaps of coin I would check the following

1 check the plugs take them out and have a look are the two totaly different is one covered in oil just before you start it ( this will tell if it is fouling up the plug )

2 do a compression test to see what is wrong it might just need a valve grind you wont no until you have done a compression test !!!!!!

3 always check all cylinders so check both first with a compression tester record the readings then squirt a whole heap of oil in thru both spark plug holes and recheck this will tell you two things which cylinder is down if any and what is wrong with the one that is down
if the compression rises a whole heap after you squirt the oil in you then no it needs a valve grind

please forgive me if I appear rude Im not trying to be Im just trying to explain what I think needs to be done so please dont take any of this the wrong way and if you have already done these things disregard my waffle

let us no what you find as in compression it might help to get peoples grey matter ticking over

good luck

Paul

Thanks Paul and OM,

I always check the obvious possibilities before asking for help. But I have not done a compression check, because I'm not sure there is enough compression to register on a gauge in either cylinder.

"So how tough can this be?
Obviously the governor ratchet ring is worn and won't hold position." Actually, NO, the ratchet ring is not looking bad and some places look like new, but the mechanism won't hold in the like-new places either.

This is not a condition that a parts replacer is going to be able to diagnose. It will take a little engineering background with old Cat experience. Sure, a person could just replace one part after another until the problem goes away, but there is a physical reason why the forces are overpowering the ratchet.

This is WORTH PONDERING: When the engine is Not running and the mechanism is in fast idle position, the slightest bump of the lever will dump it way down to near the idle position. This, obviously, IS NOT a force coming from the flyweights in the governor because we are talking about an engine at rest. Some spring tension is wrong. There are adjustments, but probably a mechanic is not going to have specs at his fingertips. I need a former Cat engineer or a commando.

I'm not interested in restoring this machine either mechanically or cosmetically. I just want TO USE it.

I do thank you guys for trying to help someone who probably seems determined to reject all advice... But the fact is, I HAVE looked into the obvious things.

I rarely come looking for help with easy things.

When the engine is not running the only source of spring return would be from the shut off spring. Look into the over center function that activates the spring.

Just because you get bit by the spark plug wire/terminal doesn't mean it is firing in the hole.

If everything is a good as you seem to think it is it would function fine so obviously there is a problem with your diagnostic logic.

"If everything is a good as you seem to think it is it would function fine so obviously there is a problem with your diagnostic logic."

Or, there is information missing. That's where all these exchanges break down. If those of us seeking help had all the information, we wouldn't be seeking help.

By the way, the reason my diesel was losing power and quitting turned out to be a lobe of cork/neoprene gasket material that had swelled into the path of the fuel pressure regulator valve--a bit of information that was missing from a long drawn-out wild goose chase trying to fix things that certainly COULD have been the problem, but turned out to not be.

Sometimes, what we don't know is pretty hard to diagnose, even when our diagnostic approach is sound.

Checking the pressure regulator valve on the transfer pump was/is one of the first things that was recommended to check. Substituting a questionable gasket replacement is a self inflicted cause.

I haven't seen a whole lot of different compression test rigs, but every one I have seen has a gauge that starts at 0, so no matter how bad the reading is, you should be able to check it. It's entirely possible that a cylinder picks up compression with a little heat and some oil splashed into the bottom of the cylinder or on the valve guides etc. You may be able to tell some difference just holding your thumb over each plug hole while cranking the pony over or rolling the flywheel by hand to feel it come up on compression on each one. Doesn't take a lot of accuracy if the problem is bad enough.

however, start with the easy stuff, plugs, wires, mag points gap etc. If you get to the cylinders, valves and pistons, remember, the head gaskets on the pony are not expensive and are even usually reusable, so it's pretty easy to pop them off and take a look inside after draining the cooling system.

Hi Jim,
have encountered the above linkage rod from the operators hand lever to the bell crank levers under the hood being bent and dragging on the hole thru the firewall. This bends the rod and puts a springing force into it that did tend to overcome the ratchet and force the linkage back to the Low Idle position.
This was most evident on units I found with the bell crank reversed to the designed orientation--check your parts book for the orientation of the long leg going to the pump control--short leg going back to the operator compartment control lever.

The pony comp test will tell us a lot. You may have a sticky valve and guide, weak valve spring, etc.
A failed top cover gasket at the inlet port will cause a weak mixture to one Cyl.

Others have covered the ignition system by inspecting the mag cap for sticking brushes, carbon tracking, rotor button for the same, wires for being full metal core wires-- e.g.-- copper or stainless steel wires not carbon--that the insulation is not breaking down.
Todays spark plugs do not have the ceramic glaze on the centre electrode and can absorb moisture, oil, carbon etc and then short out. It takes a much stronger spark to fire a plug under compression pressure and a plug that shows a good spark in the air can breakdown under pressure in the cylinder. Try some new or other known quantity clean used plugs.
Do not sand blast old plugs as you may remove the ceramic glaze and suffer these problems.
I usually clean plugs by spraying with parts cleaner, shaking dry and gently heating them over the gas stove flame to dry them off--used to 2 or 3 times carefully wash with gas and set fire to them with a match back in 3/4 Midget Speedway days.

Here, Downunder in Australia, as in the States, we now have ethanol additives in the lower grades of gas and it causes lots of problems in older engine carbies and ignition systems via the residual moisture.
I always use and recommend ethanol free Premium gas--yes it is dearer but less problematic. Premium also seems to store longer in sealed cans and still be useable.
Cheers,
Eddie B.