4.2 TD GU running rough, white smoke

[RIZZO]

Hi hoping that there are a few mechanics on here that are able to tell me what exactly is going on with my project Gu ute. Purchased the truck in a as is condition. The truck does run but only up in the revs and very rough, and theres alot of white smoke when running. What does this white smoke mean, motor low on compression? running to lean?a mechanic said if its blowing white smoke he said theres fuel getting in, but i've never heard of white smoke. anything under 2500rpm it just dies ,any help would be greatly appreciated. have checked the injector pump and seems to be working fine right up to the injectors. so its from here on in I'd say

[nilwil]

Check the coolant system , you might have a cracked head because coolant makes white smoke . My 3ltr run like
a steam train when it had a cracked head . Do a pressure test on the coolant system Good luck

[Rhysta]

A mates car is doing a very very similar thing, and I think they are currently looking at injectors and compression and pump both seem fine, pump has just had a seal kit through it.

[tweak'e]

white smoke is often due to faulty IP ie incorrect injection timing. check for fuel line blockages including the little filter in the IP. if its sucking enough air into the fuel lines it can also do it. fit clear fuel hose on the IP outlet and look for bubbles. if the pump has been worked on it may be a tooth out on the timing chain or incorrectly timed.
otherwise lack of compression will also do it.

[Rhysta]

white smoke is often due to faulty IP ie incorrect injection timing. check for fuel line blockages including the little filter in the IP. if its sucking enough air into the fuel lines it can also do it. fit clear fuel hose on the IP outlet and look for bubbles. if the pump has been worked on it may be a tooth out on the timing chain or incorrectly timed.
otherwise lack of compression will also do it.

They dont have a timing chain, are cog driven.

Like he said do a compression test first.

[RIZZO]

thanks guys, yeah pump been tested, its fine, i dare say it will be a compression matter, which isn't good, will get a test done but i think i'm wastin my time, thanks for info everyone

[kbv8ute]

Hey mate had the same problem with a wagon I bought towed it home and got it running and was blowing huge amounts of white smoke. Went down the usual avenues new injectors, fuel filter etc. had 550 psi each cyl. Found the injector pump timing was to far retarded. Factory setting is .65 lift in the pump I think and was running alot less. Advanced timing up to .96 now smoke all gone!