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Turning up timing, dirty fuel, egt's.

I wonder what more I can add for cooling. I've even vented the hood, & put electric fans behind the coolers. I wonder how much heat I'd lose going to all flat black paint?
I'm not getting into internal coatings.
I could try finding space for the coolers not in front of the radiator.
 
Looks like low boost and low EGT's. How is the smoke if any? Sounds like you could retard the timing a little and see if it changes.

:facepalm: Electric fans are a restriction when the the engine fan winds up. (So are bug screens.) Look up windmilling on propeller aircraft: it causes enormous drag. A stopped or feathered propeller causes less drag. Electric fans are for toy cars and trucks. (Or somewhere the hell else out of the way of the clutch fan.) A mechanical fan that won't keep our diesel cool due to lack of pitch moves 10,000 CFM installed with radiator restrictions and hood closed. Cheap SOB I am I tried that fan on my 1993 for one trip: windows down heater on high climbing into Lake Havasu when it was 110 out, no AC... I had a better fan with more blade pitch on the next trip. The 1998 9-blade steel and Duramax fans move even more than 10,000 CFM! Electric fans are cheating SOB's rating them freestanding without radiators or any other restrictions and even then you are hard pressed to get 5000 CFM out of a pair. Electric fans simply don't suck or blow like a mechanical fan will.

The only other fan improvement is a 100% lockup type unit.

Electric fans have a slight edge at idle for AC. Even my Dodge would benefit from an electric fan for it's design flaw AC overpressure and system blowouts, however, I am at the limit of the cooling system via power adders and the LAST thing I need is an electric fan windmill restriction in the way.
 
Maybe post pics of the fan, radiator, shroud, Etc. Maybe we spot something off.
Remember these trucks had overheating issues when ran hard stock and you have upped the pump, turbo, etc. If you haven’t corrected the old school problems yet- it wont handle anything extra.

You mentioned it has the cooling add ons, but still we dont follow it all. The known basic things to do is NO electric fans, spin on waterpump, KD clutch, 15992650 fan, 4 core high flow radiator, proper spaced shroud, highest water ratio acceptable for your environment with 2 bottles of water wetter, dual stat crossover with the restrictor or the rare 96 single with block off, Ac Delco stat(s) 190 if ambient temp is not over 100, 180 if it is.

You mentioned painting flat black- as in your radiator is raw metal? Fix that asap- oxidation coats both aluminum and copper/brass and is a horrible conductor. Salty areas oxidize them so fast it’s amazing that anything works in 5 years.

What are you running as an innercooler?

Any chance of an iat gauge in the intake?

Best “fix” for temps wmi. The methonal works amazing, but just distilled water will drop temps greatly if the added Methonal is the issue.

Where the hell is east amazonian polar region? What temperatures, humidity, and altitude are you dealing with?

What method did you use to time it? 2 non- tool methods were givin. Imo buy the timing indicator and put it on. It will take some hours, but with it installed and a timing tool the issue is resolved perfectly- no more guessing.
 
This is going to sound like I'm a ass but I'm not tiring to be....

With all the different threads you have started about first one thing then another, you just don't want to accept the fact your motor is wore out... when you push a tired wore out motor it gets hot, kinda like us old folks, and we/it won't be able to do it for long and it won't get better...

If you keep expecting more than this motor can give you will be starting a thread about a blown motor before it's over...

Put another layer of paint on the radiator and slow the thermal exchange even more if you wish, give it more fuel and wonder why it's getting hotter, is the timing right, hell we can only guess, motor blowing smoke and fumes out the cdr, wonder why???
 
Fixed the CDR, have a new one and it's fine. Oil use is very good now. I've got the four core brass radiator, heavy duty fan with the spring mod, high cfm fan, radiator is black. I was talking about the oil pan, valve covers, intake, etc painted black to help. I do have wmi, but have yet to get it to work. Something in the switch wiring, that I'll sort out.
The East Amazonion polar region is 6 degrees of flatitude smorth of Nonsica.
I'm in the process of moving from NY to VA,, that's what all this is about, so I don't have a set address to post.
I don't have the dual t stat, and I'm thinking it's a non hockey puck type, 190 degree stat.
Since it's weeping at one of housing gaskets, now's the Time to remedy that. Water wetter is hens teeth around here, I'll have to order it. Is it safe in our blocks and cast aluminum? What amount of improvement will it make?
I'm not going to get a timing tool for it. The timing tab is gone and I'll just have to time it as best I can. I'll check it with the advance rod again.
I've got ok, not great, oil pressure with Mystic 15-50 oil in it. 8 psi idle, almost 40 psi hot at road speed. I'm ok with that.
I will pull those fans. It didn't get above 210 on 750 miles back, unloaded. Ran like a champ too, 18 psi boost, quick on the hills and the on ramps.
 
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Your not an ass, I know I've posted a lot. The idea of making 6, 1500 mile round trips, half of those 9000 miles pulling heavy, sometimes very heavy loads up those I-81 hills has me very determined to get it as right as I can, with what money, time, and tools I have, without a shop to work in.
Oh, I have worn the cam bearings. The rest of the motor is good. I had it out, checked and changed the mains and rod bearings. They were good, and I was stupid enough to think the cam bearings would be too. It has ARP studs in the top and bottom ends. Cylinders looked perfect, hone marks and all. Valves were good, and new stem seals were put in. New timing gears and chain too. New oil pump just recently.
It's a fairly low mileage, maybe 80k's or so,
optimizer block.
 
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I still dont get- do you have spin on waterpump or 4 bolt waterpump? That really is a big deal. Pm on its way about the spin on pricing...

Then set timing as close as possible, and call it good I suppose. I get you have to draw the $ line somewhere.

Put a want to buy add on here for someone with the other thermostat crossover, and give a shot at 180 stat(s). If you do the duals make sure to have the restrictor in the recycle circuit, I forget what Leroy calls it but he makes a nice one. A pipe sleeve and a tig welder could save a couple dollars I guess.

You have wmi but not working yet!!??!! Oh my,
get the wmi working asap. Buying the kit or pieces to build your own was already done as the hard $ part, so yup- focus on that as soon as you do the retarder arm timing check. Maybe compare to the method WW mentioned and see if one does better than the other.

I cant remember the temp difference the watter wetter made in trucks, it’s been too long. I remember being impressed by it enough that I never ran another 6.5 (or anything else that fights heat) without it. It is not a magic bullet for everything- nothing is - it is all puzzle pieces to work together.

There is another thing you can try too, at least it can help during the move. A hummer guy, Eric, took a windshield washer resivour w/pump and reused the windshield squirters to spray the outside of his radiator. He said it made a good noticeable difference.

Pickups have a little issue with heat, hummers are worse because of the corvette like radiator angle & hood/ windshield aerodynamics and gearing that freeway driving keeps that tach in the 2800- 3,000 range. Many Hummer owers just live at 55 mph and never venture past it or tow heavy because of it. So dont feel alone in your quest.

No way would I go through stripping the paint off valve covers and oil pan to give the thin black paint job that in theory helps a Micro percentage point. If you have them off already for some other repair and want to feel better about it ok. Otherwise No. Absolutely do not add a second layer of paint to change color, that will defeat the purpose. We did the comparitive testing in the fleet and the difference was not noticeable in oil or coolant temps at all except just adding layers. Then we saw a 1* increase in oil temp. We never did actual coatings- back then that was not an option.

If you were using the actual thermal exchaning coating inside and out (notice it is not paint) then ok, that would make an actual difference and dissasembly could be justified, Maybe.
 
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Loaded is where the ECT's get you. What are you hauling BTW?

I am not a fan of modding the fan spring that others have had success with. With cooling being the difference between making the trip and blowing the engine all to scrap metal I go all out and it's worked for me. The Kennedy Diesel fan clutch is a known known and comes on for sure at a useful setpoint. It doesn't come on too early and shuts off when it should: something difficult to do by bending the fan spring. I attempted this mod exactly once on something else, the fan never shut off, and I warrantied the fan clutch.

When you are loaded towing you enter a hill, or grade out here that goes for miles, at WOT everything is "off" for cooling. First the thermostat has to open up from the WOT ECT rise. Then the radiator warms up. The ECT now will run away uncontrolled. Next the spring in the obsolete thermal fan has to heat up. Then the working fluid in the fan has to move and kick the fan in FINALLY. The delay at WOT for all these s l o w obsolete things to happen results in high runaway ECT's.

The way to shortcut this and keep ECT under 210 is to pop the thermostat sooner and kick the fan in at a lower temp. You still have a BTU limit of the system with the fan going flat out, but, getting the fan going before the ECT goes over 210 is the trick. Other extreme solutions are out there.

I have run a worn out engine as shown in the carnage thread although it had good oil pressure. Didn't help anything but it stayed under control with ECT. Thus I still think the extra fuel above what a normal turned up DB2 can provide is what's running things hot.

I have run water wetter since 2011 and only blown cheap heater cores. IMO nothing to do with water wetter. Stuff has to be put in every year as it wears out.
 
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