Cat 12 Grader main engine throttle minor issue

Good evening Russel and welcome to the board....

I'll try to get some pics of the lever and post them. Also will look at the parts book and maybe be able to help in some way.

Thomas

Hi, Russelln.
Welkum too ther 4rum. Yes, I suspect that you are on the right track as regards your throttle lever mechanism. The button on top controlled a pawl which engaged a ratchet on the underside of an arc that ran through the pawl.

[attachment=18613]DSCN0493.jpg[/attachment][attachment=18614]DSCN0490.jpg[/attachment]

These two photos are of the throttle mechanism on a Cat 22 crawler but many of the early Cat machines had a similar arrangement, including the early Cat graders.

Your grader should had oughta have a foot accelerator too, just outboard of the brake pedal. It is a good idea to get used to using this when operating instead of the hand throttle because it gives you much more control over your machine.

Here is a thread with a link in to an earlier ar-tickle that might be of some help to you with regard to your grader controls.

http://www.acmoc.org/bb/showthread.php?18595-Common-Machinery-Maintenance

The ar-tickle lists some adjustments that can be made to various parts of your grader controls to take some of the wear out of the equation and make them easier to use.

Hope this helps.

I agree with deas. If your decelerator is working correctly you only need the throttle to stay at wide open. You adjust engine speed with decelerator. Take it slow and you will get the job done. Those control levers need a quick pull or push. You can not feather them like hydraulic controls.

[attachment=18615]DSCN0178.jpg[/attachment]Thanks Guys,

The Decelerator is working correctly. It was one of the first things I discovered when I stepped on it by accident, but my issue is that with the bolt and spring setup my dad had on there I can keep the throttle full open, it vibrates it’s way back to half throttle without stepping on the decelerator.

I’m bound and determined to fix this thing and make it right.

I have already done my repairs on the pony engine, which amounted to cleaning out the gas tank and installing a basic carb kit and a new fuel shutoff valve and hoses. I also had to replace a couple of hydraulic hoses from the spooler valve to the tank. I have hydraulic Steering and a mold board which I think is the correct term that makes the blade move side to side. Everything else is gear driven.

I should mention, that YES, I changed all fluids both Gas and Diesel, I do shut the pony off by cutting fuel and not the switch. The Pony runs flawlessly and always starts within 15 seconds now where it was starving for fuel before.

I should of mentioned, that I do have the ratchet assembly as well. My setup looks like the button broke or came off and some and all the inners flew out leaving me with a floating throttle system.

Foothills of the Sierra?

Daron

Hi, Russelln and Daron.
Now I'm scratching my head. Yes, there is a DE-celerator there but it is under your heel when you are sitting in the seat. Why would you want to use that, as awkward as that would be? It was mostly only for shutting the engine down - stomp on it and you turned of the fuel to the engine.

What I was talking about was using the AC-celerator which is on the FRONT end of that same arm on the rocker pivot under the floor. This gives you WY more control over your machine than either working with the throttle wide open or trying to use that little DE-celerator pedal under your heel.

Just my 0.02.

Deas the 8T series only has a decelerator. There is no accelerator.

Deas the 8T series only has a decelerator. There is no accelerator.

Foothills of the Sierra?

Daron