P 6 Perkins run-away

Ian Beale

Member
Originally posted on the MH forum but suggested to post here also

A friend has a Sunshine Massey Harris 744 which he hasn't used for about 3 years. On starting recently it hit high revs - full throttle or run-away. (I wasn't there - I'm the one who reads YT)

Seems it has a Perkins P6 engine.

First guess would be a stuck rack.

Suggestions for fixing please and I'll relay
 
On inline pumps only takes one stuck plunger to stick the rack. Remove the pump side cover, and crank engine with all six lines loose at the injectors so it won't start. Now see if all the plungers are going down when they should while cranking the engine. If you are lucky, there will be only one or two stuck upward. With the tappet down, CAREFULLY see if you can tap down any sticking plungers with a thin screwdriver, they all need to go up-down with the camshaft. Once all are moving OK, rack should move freely too. If so tighten the line nuts and start engine. If rack is still sticky, pump may need to come apart for a complete cleaning
 
Hi Dieseltech

Thanks very much. I've relayed this.

It is a "single duty tractor" - drives his post hole digger. His last big project was about 3 years ago.

Ian
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top