white smoke and missing--help!!!

[Gyrfalcon]

I am having problems with my 1990 SAfari 4.2 liter. It starts perfectly and idles like a dream. When I am on the highway and try and pass somebody it starts to miss and blow white smoke! The smoke starts about 1800 RPMS. I have changed the fuel filter, checked for a cracked head gasket or head;( took the waterpump belt off and ran the vehicle to check for bubbles in the coolant) checked the fuel tank and fuel line; had the injectors taken out and rebuilt. By passed the hand primer in case it was leaking( air). I started putting an additive in the diesel. Could it be the injection pump timing??? I am getting frustrated. Any or all help is appreciated!!! : I am not much of a mechanic but I sure love my truck!

[nastytroll]

could be ring bypass or a bent rod will do the same thing, may also be oil being sucked from engine if the crank case breather is not working

[xenith]

the injector pump has a built in lift pump as these wear they can starve the motor of fuel at high loads maybe that is the prob i fitted an electric just after the tank on to mine from a holden rodeo wired to ING switch. Oh and make shore iu put a carby type fuel filter before it .

[Dzltec]

It sounds like a fuel restriction or sucking air. Plumb up an external fuel source to you pump, ie 4litre container, put the return hose in it as well. Go for a drive, if its fixed you know you have a fuel supply problem, if not you have a pump problem.


Andy

[canuck]

the injector pump has a built in lift pump as these wear they can starve the motor of fuel at high loads maybe that is the prob i fitted an electric just after the tank on to mine from a holden rodeo wired to ING switch. Oh and make shore iu put a carby type fuel filter before it .

Jim, this could be the ticket. You can always check this by detaching the in side hose from the fuel filter and seeing if the lift pump is bringing up enough fuel. Or you could just go ahead install an inline electric pump. You should be able to get a 24V inline pump from a Cat dealer or a Marine engine parts place. If you ran compressed air back to the tank, then that might have further damaged the lift pump. I will check my manual today and see if I can find what the pressure the lift pump is suppose to deliver. Then you can have your mechanic hook up a gauge.

John

[Gruntahunta]

"White" smoke. Is it an auto??? I remember some holden auto's had a vacuum operated diaphram between the auto and the intake that would perish and suck up auto tranny fluid under high revs. They would blow gobs of "White" smoke and run like a dog.
I may be way off the mark here but it's worth the suggestion!

Cheers............................Pete!

[Dzltec]

Yep you are of the mark, no manifold vacuum in a diesel. The use a tps switch to determine load with an auto trans.

White smoke can also be lack of internal pressure in the fuel pump, causing advance to drop off.


Andy

[BrettInUte]

last time I had that issue - I had a partial blockage in the fuel line - would run fine until the revs got up there - then white smoke and missing everywhere...