My Hzj79 (1HZ) starts and idles perfect but runs ruff and blows somewhite/blue smoke when the rpm picks up. The plunger lift on the injection pump was at .80mm and I had it reset to spec at GCL fuel systems in Calgary to 1.20mm. It solved the problem temporarily and was running perfect. After about an hour of run time the problem started up again. It gets gradually worse until there is hardly any power. White smoke at high rpm again and little power. Still starts and idles perfect. Resetting the the plunger lift fixed the problem but what could be causing it to go out? Any ideas?
Injection pump timing 1HZ
- Thread starter sitkocreek
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White smoke and lack of power, have you changed both fuel filters,mine did the same and found fuel filter blocked
- Thread starter
- #3
All new filters. I'm thinking it is a fuel feed problem and just need to figure out where the problem is. But what I cant figure is why the pump timing would go out again. Would a fuel feed problem cause this??
The fuel feed on these pump as much as 4 times what the engine can consume,it would have to be a really old pump to have a worn out fuel feed.
The fuel feed on Denso pumps is much more efficient than north american style pick up trucks which do have fuel feed problems occasionally
You could rig up a gravity feed with a can of clean diesel direct to the pump to satisfy yourself it is getting enough fuel.
I cant see why the plunger lift would change after it was set. The original setting of .8 may represent the wear inside the cam plate(Im guessing)
The tolerance of the plunger inside the injector head is very fine and when they warm up,they lose the abilty to compress the fuel enough to open the injectors properly.
You could also have weak injector springs which allow the injector to open early
I had a look at GCLs website and would have thought them professional enough to sort it out.
How many K's on your pump and injectors ?
Did you know their is a filter inside the injector pump under the fuel cutoff solenoid?.
The onley other thing that i have seen affect the timing is the idler gear in the frount timing cover, it runs on a sharft and when it wears it retardes the timing.If the vacume pump is taken out you can see the gear has aney play.
The onley other thing that i have seen affect the timing is the idler gear in the frount timing cover, it runs on a sharft and when it wears it retardes the timing.If the vacume pump is taken out you can see the gear has aney play.
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i had delivery problems when my pickup screen in the tank clogged.
