1hz + turbo 110km/h with aircon

[Simozed]

hi everyone, i have a 94 hzj75 ute denco turbo with boost compensator and its getting hot when doing over 100 with aircon on ( usually just on hot days). so far ive replaced most of the cooling system fan clutch , rad hoses, flushed rad, Thermo stat (76 deg) , new belts the fan clutch failed a while ago so i replaced alot of things while i was there. this fixed it for the most part but its still getting warm. i was thinking of turning down the fuel slightly as at 110 with ac on it sits about 7-8psi and 450 deg give or take a little depending on head wind , grade of road ect.

im not sure its a cooling system issue as such , perhaps just a little too much fuel im unsure.

should i

a. pull rad out and get the thing cored and cleaned and replace water pump .? ( i think the rad is in good condition, i think also the water pump was replaced about 25k ago )
b. turn the fuel down slightly and see if it affects the coolant temps

with option B should i adjust the boost compensator as to not add as much fuel under boost, or adjust the main screw. i havent played with the compensator yet so dont know alot about how to adjust it.

a note. i recently went for a trip to the beach and it went flawlessly, Accept....... on the way there on the flat road with ac on about 30+deg day doing 105-110 it started climbing to about 2/3 on the stock gauge i had to back off to 100 and baby it (just very light on the throttle ) to keep it cool. it was weird caus theres some big hills on the way and it never got hot on the hills at all, and i sat on 110 nearly the whole way back and it never got hot ( was dusk/evening so about 24 deg ambient)

 

[roscoFJ73]

Maybe the best thing would be to add a an aftermarket temp guage so you know exactly how hot it is. 2/3 on the stock guage is not in the red so technically its not over heating.
Even on my non turboed 1HZ with a good cooling system,coming down from up north on flat roads I can make it move to 2/3 up the gauge if I push it on warm days.

If t only takes a few degrees lower ambient temps and all the problems go away,Im even more inclined to think you don't have much of a problem.

On the subject of radiators,the 78/79 series with the 1HD FTE have a slightly higher volume radiator Ive heard. But the downside is they are plastic and aluminium.

 

[Simozed]

Installed this this arvo and took it for a spin, got to 93 deg and the stock gauge was just past half way. 110-120 with ac on mild head wind and about 27 deg day. It takes about 10mins or so then the temp starts climbing slowly at that speed. I am thinking about intercooling I think this will help a lot.

 

[Dougal]

Where is your EGT probe that reads 450C? I'm guessing post turbo.

The only solutions to lean out your engine and get more cooling air through it would be an intercooler (difficult in the 70 series I imagine) or a turbo with a tighter turbine housing to produce more boost.

 

[Simozed]

Where is your EGT probe that reads 450C? I'm guessing post turbo.

The only solutions to lean out your engine and get more cooling air through it would be an intercooler (difficult in the 70 series I imagine) or a turbo with a tighter turbine housing to produce more boost.[/QUOTE

Yeah post turbo readings , I'm going to back the fuel off slightly today it is running heavy on fuel I can push it to 550 up hills rather easily and if I didn't back off the pyro would keep climbing, I'm still not sure wether it's best to adjust the boost compensator or just the main screw ?

 

[Dougal]

The only fuel adjustment that will help it heating at 110km/h is to reduce fuel until you can't do 110km/h.

I would move the pyro probe to pre-turbo. Then see what the real temps are and look at increasing boost. If the turbo won't increase boost then you'll need a better, more responsive one or an intercooler.

 

[Tapage]

wonder if when coasting and water temp needle on stock gauge ( as said here install and trustable aftermarket one ) start climbing you were in 5th .? so downshifting to keep the same speed ( going up in the rpm range ) help with the temps ..?

 

[chappohj47]

Hi mate I have a hzj80 with 1hz turbo and aircon mine sits at 68 all day long doing 100kms only half way on standard gauge