12HT engine sensitive throttle Kangaroo hops on low RPM

Naveed Merchant
I think I originally suggested the new ball and arm extension.
You have to ask yourself why a mechanic can't recognize or find the ball in question and fit an old piece of carby arm, complete with ball, and attach the throttle cable to that.
It may not give you, (may not), full throttle but you will never need it anyway because unless you are going to try and drive at 160kmh then it won't matter.

The new Ball has to be further away from the OE throttle arm pivot.

Who ever suggested tightening the pinion bearings, I presume tighter than spec preload, is off their heads and don't know it will destroy the front pinion bearing an then the diff.

Don't believe what you read on the internet and therefore don't believe me either. You decide on that one.

The internals of the pump governor and fuel rack sliding resistance of 4oz is a techo thing to set and most don't know how.
Find a pump service centre for that.
Cheers
Ross M

I don't know exactly the cause of the problem but it is far from uncommon in larger diesels with a bit of age under them.

Its a problem progressing from idle to power....its called "hunting"

An old Mack tipper I was driving had a shocking case of it especially when hot comming off a high speed ( 80 pluss Kmh) run.

It was embarasing comming up the drive on the way back to the hard stand going Burp Burp, Burp, Burp.....it would even do it with the foot right off the throttle.

The boys in the workshop had it one weekend and when I got in it Monday morning, It went an extra 10Km an hour faster ( it would nearly do the speed limit on the freeway) and progressed from idle to power smoothly....what they did I have no idea, but it had nothing to do with the diffs or gearbox.

Some diesel pump adjustments is my guess.

cheers

I am today with mechanic and going through all the checklist suggested here in this post.

I just read an interesting post some years back suggesting to install a device thingy to dampen the lower swing of the throttle actuator arm. This is found in cars with petrol fuel injection.. they have a dampener device which has a spring plunger that travels slowly, as if in oil, and it slows the snap back of the throttle arm at the bottom of the swing.

Any idea which vehicle or engine model of this dampener work on 12HT? The picture of this is shown here http://forum.ih8mud.com/diesel-tech-24-volts-systems/232329-kangaroo-engine.html

Any idea where i can find compatible small "shock" absorber in the linkage system. So when I plant my foot down, the damper absorbs the punch and delivers a smooth accelerating vehicle. Also probably dampens offroad pedal wobble.