06 fuso fe over heating

[boostin]

I did some testing on my 07 FE yesterday. Temps were in the mid 90's *F, the air conditioning was on full blast. Flat highway, no traffic to speak of, top speed of 78 MPH. Temp gauge went all the way through the red zone and hit the line on the other side within a few mins of getting on the freeway.

Slowed down to 60-65 mph and within 2-3 seconds, the temp gauge was below the half way mark. I cannot imagine the engine coolant shedding or dumping that much heat in that amount of time, so I am doing some trouble shooting to determine what may be the culprit. If the thermostat were sticking, the temps would not come back down under half mark. Same for obstruction in or on radiator, etc.

Dealer says EGR plate style cooler, faulty gauge or new radiator are his top three choices for fault.

We don't have physical vehicle inspections where the truck is registered and there are no emissions inspecitions for diesel trucks, so if there is a safe way to do it, I am keen to rip the whole damn thing off and toss it in the scrap bin.

Some one please try and follow me and see if this makes sense cause it is 3am my time.


Where is the temp sensor for the coolant gauge on the dash?

Is it possibly right beside the rad cap?

What is prob the biggest restriction with the whole engine that makes the most amount of heat?

Sure seems like the micro turbo.

Where does the coolant from the super heated turbo return to?

Could it be plumbed directly into the rad cap housing where the sensor is?

Maybe the engine is not getting super hot just the gauge thinks it is cause of the placement of it to relation to the turbo coolant return.

Could explain why the coolant seems to drop so fast when you let off.

 

[pugslyyy]

Disabling any part of the emission systems is illegal, so who would do that?

But... speaking hypothetically, should the flow of exhaust gas to the EGR find that it's been blocked, by lets say a blanking plate in between the crossover pipe and the manifold, you won't be seeing any extra illumination on the dash and your engine will be happier than it was previously.

Good to know, thanks.

 

[westyss]

Disabling any part of the emission systems is illegal, so who would do that?

But... speaking hypothetically, should the flow of exhaust gas to the EGR find that it's been blocked, by lets say a blanking plate in between the crossover pipe and the manifold, you won't be seeing any extra illumination on the dash and your engine will be happier than it was previously.

Oh! Ahem.....right...................now I remember you were only thinking about it.

 

[kerry]

Are you sure your fan clutch is working correctly? Symptoms are consistent with a fan clutch not-engaging when it should.

 

[DzlToy]

On my truck, the fan comes on almost immediately and runs the whole time the truck is running. A mate of mine said I should try to stop it or slow it down somehow and see if the fluid coupling is really engaging how it is supposed to. Maybe its not turning fast enough, but I am not willing to do that, in case it is working correctly.

On my 4Runner, I replaced one years ago and it was very obvious that it had failed. Not sure if this is the case with an FE clutch or not.

I will be using the truck this week and will try to get the truck hot and quickly look under the truck to see if the fan is turning, but with the temp dropping from red zone to under half way mark in literally a few seconds, I imagine this is going to be tough to do.

 

[kerry]

The fact that the fan is turning isn't an indication that the clutch is working. It will always turn even if the clutch has failed. It's hard to determine if the clutch is working or not. After the engine has started and run a few minutes but is not yet hot, shut it off and spin the fan by hand to see how hard it is to turn. Should turn fairly easily. Do the same thing when the engine is overheated. If the clutch is working it should be much harder to turn.

I was able to diagnose a bad fan clutch once by climbing a long steep hill. Engine was very warm but not overheated as I was driving about 55 mph. Pulled in behind a big truck which cut off the air flow and temp immediately spiked so I knew the fan wasn't pulling air thru the radiator.

Also just last week I was having some temperature problems with my 9 GMC 6.5 diesel. Upon inspection I discovered someone had installed the fan blade backwards on to the clutch.

 

[kerry]

By the way, under the right conditions I can tell my fan clutch is operating by watching the temp gauge. When I was driving across I-80 in Nebraska in my GMC last week when it was about 95 degrees and road was dead flat, temps would slowly climb from 190 to 204 or 5 when the clutch would engage and temp would drop to about 180 when it would kick out and temp would slowly climb again to 204 or 5 when the cycle would repeat.

 

[boostin]

Some one please try and follow me and see if this makes sense cause it is 3am my time.


Where is the temp sensor for the coolant gauge on the dash?

Is it possibly right beside the rad cap?

What is prob the biggest restriction with the whole engine that makes the most amount of heat?

Sure seems like the micro turbo.

Where does the coolant from the super heated turbo return to?

Could it be plumbed directly into the rad cap housing where the sensor is?

Maybe the engine is not getting super hot just the gauge thinks it is cause of the placement of it to relation to the turbo coolant return.

Could explain why the coolant seems to drop so fast when you let off.

No one thinks this is valid?

 

[DzlToy]

I have no answers to your questions, sire.

I did turn my fan last week when the truck was off and not overheating and it was "relatively" easy to turn. I should be able to check it this week and will be with the truck for a few days if I need to look for sensors or wires, take pics, etc

 

[kerry]

Some one please try and follow me and see if this makes sense cause it is 3am my time.


Where is the temp sensor for the coolant gauge on the dash?

Is it possibly right beside the rad cap?

What is prob the biggest restriction with the whole engine that makes the most amount of heat?

Sure seems like the micro turbo.

Where does the coolant from the super heated turbo return to?

Could it be plumbed directly into the rad cap housing where the sensor is?

Maybe the engine is not getting super hot just the gauge thinks it is cause of the placement of it to relation to the turbo coolant return.

Could explain why the coolant seems to drop so fast when you let off.

The turbo is cooled on this model?? Never heard of that.

 

[kerry]

Another thing which could be causing overheating is a dirty air filter since it makes the engine run rich increasing the EGT's and driving coolant temperatures up. A pyrometer would confirm whether this is the problem.

 

[pugslyyy]

The turbo is cooled on this model?? Never heard of that.

I think there is an air-to-air intercooler, and of course oil for lubrication.

 

[boostin]

Yes the turbo has oil and engine coolant going through it

 

[kerry]

Then high EGT's would drive the coolant temperatures up even more quickly.

 

[pugslyyy]

Yes the turbo has oil and engine coolant going through it

Pretty sure mine doesn't, but could be wrong.