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Hot truck, why, high boost, bad IAT, cooling issue???

Have you changed your coolant sensors? They could be getting flakey.

With the new motor install I have an Autometer temp gauge that is switchable between oil temp and coolant temp. Mounted sender in port located rear PS head. Also have ScanGauge installed.

There is about a Autometer runs about 10deg cooler than OEM dash gauge. ScanGauge temp runs about 10deg cooler than Autometer.

Oil temp is running about 30deg cooler than H2O temp.
 
TCC lock mod may help by not putting piping hot tranny fluid through your radiator? I'v heard it helps poeple towing, but me being obd2 its just another mod i'm jealous of... I'd love to be able to lock mine at will.
 
Kenny. I recently(within the past month or so) had ~7-8K behind my truck(dual axle car trailer and 86 f-150), and ECT's never went above 195*F. Boost was 14 psi, EGTs at 900-950* pre-turbo or so. That's up a really steep hill(not sure of grade but its ~1.5 miles long).

My truck doesn't have A/C, so no condenser. That may be your issue. My truck has the HO Wp and dual stats stock(and the pump was a week old when this tow occurred). Short of that your truck's got almost the same mods as mine, except i've got a GM-5 and you've got the FTB mod. I'd say try your A/C idea. The condenser may be your issue.
 
Acesneights1 said:
Well it's an easy enough experiment to pull it out.
Click to expand...

Might as well clean the piss out of it while its out too...

Kenny, Have you checked your A/f mix? perhaps your have way too much green for fear of freezing?

Can't hurt to test it and toss in 2 bottles of watter wetter...
 
LOL, the seasons are coming full circle once again...

Snow melted
Warm weather here
baseball begins
Basketball playoffs

Kenny's thread about one of his 6.5's overheating while pulling a camper...
 
Yeah well, I thought I solved it by selling the camper. It has 2 bottles of waterwetter and coolant mix is perfect. I tossed the dexcool and am running lifetime. The problem has never been solved.
 
I'm sorry if its been asked before, but at what temp does your fan kick in, and does it stay on when you need it most?

I know its the Heath super duty, but doesn't mean its working proper.
 
Man, oh man, Kenny... you didn't do the TCC lock Mod, did you? Grrr....

I pull 9800# high-front 5er with my truck,Buddy, and I have a GM4. And AC. And a single Thermostat. And a Turbomaster, pushing 12-14 psi.

Cooling in a 94 or 95 is a matter of doing a lot of things - they each contribute a little.

1st - clean rads. REALLY clean - I know you got a new one, Kenny, I remember that. Is it a 4-core factory one, or one of the 2-or-3-core remans? Clean rads, clean coolers, take 'em right out and soak and wash until they are spotless.

2nd - Heath SD Fan clutch - kicks in a little earlier, transfers engine torque to fan a whole lot better. When that baby engages, the temps come down. Mine kicks in just under 100*C. Video here

3rd - Genuine ACDelco thermostat (for single Tstat systems). Don't even THINK about using anything else. Yes, I know the Stants are $22 cheaper. How much is your engine worth?

4th - TCC Lock mod. When you are pulling, if you can lock that Torque Converter, you will dramatically reduce the heat generated in your transmission - which ends up being dumped into yur Rad, which ends up drastically reducing your cooling efficiency. 3 wires, 1 switch... priceless.

5th - finding the sweet spot. Every truck has that 'sweet spot', the combination of speed, tow weight, gear, wind, all that stuff... where she pulls hard and cool. Go faster than that, you overheat because you start to generate too much EGT. Go slower, you overheat because you start to lug and generate more tranny heat. Find the sweet spot. You may find that 60 mph in 3rd (locked) is better than 60 mph in 4th... and when it runs cool, you will use less fuel.

Wind resistance is a factor in the speed thing, if your front is high like mine. When you hit the wind, not only is the surface area an issue, but the drag is a function of the SQUARE of your velocity, so even 5mph could be a big difference. Find the sweet spot.
 
Top mount I/C with the PR45 scoop...Now that's what I'm talkin about...
http://www.up22.com/scoopw3.htm#PR-45
That'll get rid of some heat old school.
:)
The only thing I need to check is the rad but I know when I put them side by side they were exact of course what i didn't think of is wouldn't it be a bitch(btw you just made me think of it) if and this is a huge what if the rad was replaced by PO with el cheapo rad and then when I bought my new aftermarket one it looked the same as el cheapo because now that you are saying that I am pretty sure this rad was 3 core but I'm so bent right now thinking on it I'm walking outside to look. BTW would ya help a feller out witht at TCC mod link again. I will do it this time or face the cat of nine.
 
Can't tell. forgot no cap on the rad. Like I said before the problem was somewhat licked until I put the TM on. maybe the boost she a little too much. I hate to cut it back though. SOP meter a 9.
 
Like I have said before though my 2000 is actually worse and I pulled everything outta that one too and cleaned it. I'm just a jinx.
 
Is that airbox cut open mod an open filter right next to the turbo? or did you cut open the fenderwall? Have you ever upgraded that airbox to 97+ type?
 
Based on my snapshot it looks like high IATs are defintely part of my problem, now the solution is a tossup between a topmount I/C and a hood scoop or the ATT. I'm really not into a hanging I/C. Ideally if time were on my side I really want to ditch the A/C condsor uner the truck with elec fan and then mount an I/C in it's place. Now that would be the bomb..
 
Electric fan would make it worse, IMO those don't pull near the air the mechanical fan does, with a good fan clutch. I called a couple of electric fan vendors once, they did not recommend them for the Diesel.

Ken I'm still scratching my head for yours, you should not need that much boost, and temps should not be that high,.
 
Yeah I'm scratching too but I'm Irish so it's never simple. It's always someting no one has ever seen before...:)
The electric fan I mentioned would be for the remote mounted a/c condensor not the engine rad. I have set up a few a/c systems on heavy equipment/trucks that way and it was fine but I agree electric cooling fan on the rad would actually make it worse on the highway because it can actually block air at highway speed, in other words the fan isn't allowing the air through as fast as it would go naturally. They only really work at low speeds. My problem is at high speeds.
I really can't do anything until I pick the camper up hopefully next week. Then I will try a few different things starting with reoving the a/c compressor. I'm going to look at the turbo today as it has oil around it so tha desicion may make itself. I got get a new IP too. Ughhh where does it end. If my pickup needed all this stuff it would be on ebay right now but I really do love my 2 door. It's actually no longer cost effective to keep this truck, it hasn't been for awhile. It's a labor of love now.
 
Acesneights1 said:
Yeah I'm scratching too but I'm Irish so it's never simple. It's always someting no one has ever seen before...:)
The electric fan I mentioned would be for the remote mounted a/c condensor not the engine rad. I have set up a few a/c systems on heavy equipment/trucks that way and it was fine but I agree electric cooling fan on the rad would actually make it worse on the highway because it can actually block air at highway speed, in other words the fan isn't allowing the air through as fast as it would go naturally. They only really work at low speeds. My problem is at high speeds.
I really can't do anything until I pick the camper up hopefully next week. Then I will try a few different things starting with reoving the a/c compressor. I'm going to look at the turbo today as it has oil around it so tha desicion may make itself. I got get a new IP too. Ughhh where does it end. If my pickup needed all this stuff it would be on ebay right now but I really do love my 2 door. It's actually no longer cost effective to keep this truck, it hasn't been for awhile. It's a labor of love now.
Click to expand...

Aces -


As Buddy said before, running 14.4PSI of boost (as shown in your snapshot) is waaaaaayyyyy too much boost for a GM-4 turbo. Drop it back to 9 PSI sustained via scan tool and watch what happens. As he also alluded, your 14.4 PSI of boost on the GM-4 equates to roughly the same level of temperature rise as a "normal" turbo at 22PSI. With the GM-4 at 14.4 PSI, you are probably pushing 35 to 38 PSI of turbine drive pressure...:eek::eek:

This would also explain why everything was "cool" until the T/M...

Something to ponder...

Regards,
 
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