I need some verification with my diagnosis. I overhauled this A/C 7040, replaced crank,all bearings, Rings,( Pistons were good, They were replace 3yrs ago along with the sleeves) One connecting rod #4 cylinder, Timing idler gear bearings,( .010 lash on gears) and had the head gone through at machine shop.
My problem is that the engine is very hard to start, and has a sharp knock ( sounds like an injector.(I pulled all the rerbuilt injectors out and tested them, all are popping off at 3750 psi. and have a good spray pattern). This knock is most noticable off idle on accell, and is not as bad when warmed up. there is alot of smoke during starting(only will start with either at 3/4 throttle, and takes along time to get going, like timing is retarded) I am positive of cam timing and originally the pump timing ( by the book) was set to 16 deg BTDC.
I have increased timing to 20 deg BTDC and it helped a little but still smokes alot(Grayish white and a small puff of black on accell) Acelleration is not quick. The pump is a stanadyne and lookes fairly new. I feel my problem is with the injection pump. It did start better but smoked and had a rod knocking and #1&#2 piston rings stuck. Center head bolts were rusted( head was machined) new headbolts were installed.
Am I on the right track with the pump or should I be checking something else? I work on GM Diesels all day long, and this simple tractor is getting the better of me. Any help or suggestions would be appreciated. hal
My problem is that the engine is very hard to start, and has a sharp knock ( sounds like an injector.(I pulled all the rerbuilt injectors out and tested them, all are popping off at 3750 psi. and have a good spray pattern). This knock is most noticable off idle on accell, and is not as bad when warmed up. there is alot of smoke during starting(only will start with either at 3/4 throttle, and takes along time to get going, like timing is retarded) I am positive of cam timing and originally the pump timing ( by the book) was set to 16 deg BTDC.
I have increased timing to 20 deg BTDC and it helped a little but still smokes alot(Grayish white and a small puff of black on accell) Acelleration is not quick. The pump is a stanadyne and lookes fairly new. I feel my problem is with the injection pump. It did start better but smoked and had a rod knocking and #1&#2 piston rings stuck. Center head bolts were rusted( head was machined) new headbolts were installed.
Am I on the right track with the pump or should I be checking something else? I work on GM Diesels all day long, and this simple tractor is getting the better of me. Any help or suggestions would be appreciated. hal
