1HZ smoke (muppet) question (sorry!) (1 Viewer)

[bill91817]

quick smoke quesiton on my troopies (1997 HZJ75) ageing 1HZ

on a run donw a big hill - running against compression all the way donw at about 60kmh for about 4 minutes, get to the bottom and put the foot down - fair bit of white smoke out the exhaust for a good 15-20 seconds, also after being sat at the traffic lights for a while and then on take off a small puff of smoke (grey/white)
Wife was driving behind me up the hill the other day and said was blowing a bit of white/grey smoke (under load)
Assume that my valve seals are worn, we use a bit of oil but not much - could the smoke under load be underfueling?
She has done 360,000km and starts fine cold but after a long run turns over a lot before firing - assume this is because the oil is "thinner" when hot which means compressions must be down too?

 

[ozcrusier]

forum.ih8mud.com/threads/diesel-smoke-questions-read-this-first.273850/

 

[bill91817]

thanks mate

 

[roscoFJ73]

Running against the compression lowers the exhaust gas temperature and the white smoke is most likely a product of that(combustion that is too cool).It is mainly condensation. I can drop the coolant temperature from the cyl head from 90c to 50-60c in that amount of time coasting down a big hill in gear

The other problem of hard starts when warmed up is often a symptom of a worn injection pump. If it hasnt been rebuilt in 360000klms ,you have had a good run that has come to an end. Needs a bench test to confirm.
Another symptom of a worn fuel can be a loss of power at the top end when warm but ok when cooler.
This is the pump expanding , losing the fine tolerance and the ability to squeeze the fuel through the injectors.
When it cools and contracts ,it's ok.
The rest of the engine is probably fine , its just having a mid life crisis.

 

[bill91817]

Running against the compression lowers the exhaust gas temperature and the white smoke is most likely a product of that(combustion that is too cool).It is mainly condensation. I can drop the coolant temperature from the cyl head from 90c to 50-60c in that amount of time coasting down a big hill in gear

The other problem of hard starts when warmed up is often a symptom of a worn injection pump. If it hasnt been rebuilt in 360000klms ,you have had a good run that has come to an end. Needs a bench test to confirm.
Another symptom of a worn fuel can be a loss of power at the top end when warm but ok when cooler.
This is the pump expanding , losing the fine tolerance and the ability to squeeze the fuel through the injectors.
When it cools and contracts ,it's ok.
The rest of the engine is probably fine , its just having a mid life crisis.

thanks Rosco - i was going to flush the engine with CEM to see if that helped (suggest the rings etc have some build up) just had the injectors done and that made a bit of difference (to power) will look at a pump recon - presume that wont be cheap!
cheers
billy