4020 runs rough

[binki88]

i replaced injector pump now it runs rough. starts right up but wont bring rpm up right away and on the way up she gets rough like its suckin air or outa time. im sure theres no air left in it shouldnt have a timining problem put pump in after brought the motor to top dead center. just woundering if anyone has any ideas?

 

[LarrySTN]

You didn't say, was the pump rebuilt or new. The pump has slots, at the base, how how did you time the pump on the base? It sounds like the pump is retarded ( pump needs loosened and rotated) or the injection advance is not working, or the pump wasn't properly rebuilt and possibly has a bad delivery valve or the rebuilder installed the cam backwards. This all providing the engine had no other issues prior to the removal of the pump.

 

[David G]

The pump will only fit one way without forcing it. There is an offset slot in the oil pump drive that takes the male from the bottom of the injector pump.

New pump ????, please let us know what that means.

 

[LarrySTN]

Yes the pump shaft is offset, but there are slots where the nuts and washer hold the pump to the block. The pump can be rotated at the slots several degrees. The flywheel needs to be turned to TDC and the timing cover removed from the side of the pump and the pump rotated untill the two marks inside the pump aligned. If there is only one mark visable the flywheel needs to be turned one complete revolution then procede with pump timing. This has been covered many times on this forum.

 

[binki88]

the pump is a rebuild. tractor ran fine before i think it is the timing. any way to set it or just loosen the nuts a turn till smoothes out?? thanks!

 

[msb]

Blow out the ful return line.Probably about plugged with bits of plastic from the disintrigated elastic govenor ring.

 

[David G]

Timing is real simple.

Take the timing cover off the side of the pump and the flywheel cover. You can rotate the engine (in the normal direction) with a screwdriver on the ring gear. The TDC timing marks on the flywheel and the two marks on the pump should line up at the same time.

 

[binki88]

thanks guys gonna try and blow the return line out ill let u no if it works! thanks again!