8V92TA Running Hot

[Truck Shop]

Ok-It's had stats, water pump, radiator core cleaned, fan hub rebuilt, belts, shrouds are in-place, nothing
obstructing air flow to radiator. Any extra crud should have been found in core if it came from block.
If it was that far out of tune it should be low on power and high fuel consumption, more than it would
consume normally. If it had psi above normal in the coolant system it should be pushing coolant past cap.

So tear down time.

 

[willie59]

I agree with truck shop, all the work/parts you've done and the overheating has been progressive over time, it's a good possibility crusty stuff is blocking coolant ports in the head and/or block restricting coolant flow. Now matter how good the pump is, rad, thermo's, if it can't flow it won't cool. Tear the heads off and get a look around in there.

 

[Huffa]

Coolant 50/50. Clean as a whistle inside waterpump

 

[willie59]

Coolant 50/50. Clean as a whistle inside waterpump

That doesn't necessarily mean the innards of the engine is clean as a whistle.

 

[Truck Shop]

Thank You Willie.

 

[Huffa]

Yip I hear you. So waste of time just cleaning the after cooler and a tune? That was my next move

 

[willie59]

Yip I hear you. So waste of time just cleaning the after cooler and a tune? That was my next move

I don't know about the after cooler to be certain, but logically if the after cooler were clogged it would restrict intake air flow which would decrease the air charge inside the combustion chambers which would typically produce black smoke because the air/fuel ratio is now out of whack. With enough reduction in air flow/air charge then the engine would suffer from power loss as well, it would run like crap. Whether or not it would cause overheating, don't know, but really doesn't make logical sense. That's just me thinking out loud.

 

[Coaldust]

Check the delta T across the radiator when She’s hot and bothered and the T-stat is open. Grab a infrared thermometer. 7-12 deg. F is normal. Greater than that = flow problem.
Less than that = capacity problem.

Doesn’t cost anything and takes the mystery away.

 

[mekanik]

Does this truck have shutters in front of the rad?

 

[1693TA]

I've seen a couple of V-92TA engines with much the same problem experienced in this thread. Both were clogged intercoolers under the blowers. Both engines had defective rubber elbows and joints on their respective air filter housing plumbing installations. One, (truck installation) had a small hole pierced in a rubber boot for ether injection to be covered by adhesive tape afterward, and the other, (standby engine generator) had deteriorated boots. Both engines had a "carpet" of muck on their respective coolers. Power was down and smoke was up as was operating temperature from the resulting over fueling. Neither engine was hurt and performance returned to normal after cleaning and routine maintenance adjustments.

 

[willie59]

Check the delta T across the radiator when She’s hot and bothered and the T-stat is open. Grab a infrared thermometer. 7-12 deg. F is normal. Greater than that = flow problem.
Less than that = capacity problem.

Doesn’t cost anything and takes the mystery away.

That's what we're looking for, techniques for narrowing down the issue of cause. Huf stated it was a progressing problem, not "always had this problem", meaning, it has progressively gotten worse, meaning, something has changed. Not a sudden change, as in something went south, but for sure something has changed or is in the process of change. This is an interesting problem, one I'm curious to follow to conclusion.

 

[Truck Shop]

After sleeping on it, one from the past.
Farmer brought a ten wheeler in with a smoking low power issue, not necessarily a heating issue.
After looking it over I noticed something rather odd, {this was a 855 Cummins}. I removed the
crossover from aftercooler to turbo used a scope to see, then called farmer. He and his son showed
up, I pointed to the aftercooler with a question, who's been greasing this truck? Son said I have.
The farmer had removed the ether start and plugged the the port with a zerk, two years before.

Now it smoked, was down on power some but really didn't cause a heating issue. Something that
happened over time.

 

[Huffa]

Thanks for everyone's input, it's much appreciated, some good ideas been thrown around

 

[Huffa]

Is there any way that I can flow test the cooling system if I installed some full flow thermostats?

 

[mekanik]

The aftercooler in that engine is tiny. I can't imagine how it could make any difference in power.
They were notorious getting plugged over time.

 

[1693TA]

The aftercooler in that engine is tiny. I can't imagine how it could make any difference in power.
They were notorious getting plugged over time.

When that core is plugged from foreign matter it precludes free flowing air much the same as a severely restricted filter. The two stroke engines require all the breathing air they can get and when it's restricted, power falls off quickly. Engine temperature elevates also as the intake air is not cooled unbalancing the fuel/air ratio and driving up engine heat as a result.

 

[Truck Shop]

One question the OP hasn't really answered, is it producing more smoke than it use to
and is it low on power.

 

[Coaldust]

Difficult to flow test, but you certainly can check pressures. But, similar and more useful data can be collected by checking water in, water out and water mix temps.

So many weird things can slow coolant flow. Like a deteriorating hose liner plugging the oil cooler inlet.

Another cheap trick is to spray the radiator with water to detect a cold spot.

If the coolant stays in the radiator too long, the temp difference between top tank and bottom tank will be significant. That indicates a flow problem.

Our industry has forgotten how useful a pyrometer can be. Exhaust temps can shed light on intake restriction or over-fueling issues in real time.

 

[Truck Shop]

That indicates a flow problem.

Or a radiator/cooling system that is flowing well and cooling.

 

[Truck Shop]

Like a deteriorating hose liner plugging the oil cooler inlet.

Or blue paper shop towels someone shoved in open hoses/ports while doing repairs
and forgot to remove them. Have found two 3406's that had plugged oil cooler
after water pump change.