thermostats

[heavyhaulerss]

what would happen if the thermostats were removed. i have a detroit engine & during the summer months the water temp gets too high too quick. & takes the fan longer to get temp back to normal. replaced thermostats. water pump o.k. new radiator, new hosese. e.t.c. when going up hill loaded, temp climbs really fast. not losing water. i remember removing my thermo's in my old 1970's cars & they ran a lot cooler during the summer & i would just put them back in before the winter. i dont know how a diesel engine would run without thermostats. i just know last year i had to run my fan a lot. & trying to figure something out that may help me before the hot days get here. the truck came with 190 thermo's i put in 180 thermo's wich helped a lot but it stays min 190 to 215. running 40,000lbs up slight hill i have to run fan. was thinking either remove thermo's or putting in 170 or 160 degree thermo's..?????? thanks

[Bandit102]

There's a small hose, maybe 3/8" dia. that comes off the thermostat housing and goes to the radiator tank. Pull it off the radiator, and run the rpm's up. Coolant should shoot out of it, I mean shoot out. If not, take the hose fitting out of the thermostat housing and dig the mud out of it.

[allan5oh]

I would fix the problem instead of putting a bandaid over it. Pulling the t-stat may not even help.

[Bandit102]

That's what I was getting at, Allan.

Even though my Detroit was consistantly blowing head gaskets, even with a blown head gasket, IT NEVER HEATED. Something is wrong somewhere and the bypass hose is the only thing I can think of.

[heavyhaulerss]

I would fix the problem instead of putting a bandaid over it. Pulling the t-stat may not even help.
_________________

i agree. i have spent money on process of elimination, because no one could tell me exactly what is causing temp to rise. so to fix.. i have to know what is wrong & even williams detroit cannot reach a conclusion. all say basically the same thing as when i 1st encountered this issue.. goes like this... sounds like thermostat. put in. still run too warm..next.. sounds like radiator. put one it.. still runs too warm.. next water pump.. put one on.. next... ya know that is about the right temp. i know my truck & what temp it has run for 8 years uphill down hill loaded/unloaded. & i know when it runs at a consistant higher temp than ever before. the last diognosis i heard was sys may need to be cleaned with cascade run thru sys to remove buildup that is too thin to see with the naked eye. lol. believe me i dont mind spending any amount of money to fix any problem. but i hate throwing good money after bad. i will look at hose coming off thermo housing as suggested.i do remember taking off & replacing all my hoses. will have another look. thanks for the help. if hose is clear.. i guess i'll have to try different temp thermos or remove them this summer. i am at a loss at to what to try next. add up the cost of all i've done plus the downtime & still have the problem?? sooo unless someone can give me advice that i have not already tried. i have no choice but to remedy this myself as foolish as it may sound.

[bob h]

what would happen if the thermostats were removed. i have a detroit engine & during the summer months the water temp gets too high too quick. & takes the fan longer to get temp back to normal. replaced thermostats. water pump o.k. new radiator, new hosese. e.t.c. when going up hill loaded, temp climbs really fast. not losing water. i remember removing my thermo's in my old 1970's cars & they ran a lot cooler during the summer & i would just put them back in before the winter. i dont know how a diesel engine would run without thermostats. i just know last year i had to run my fan a lot. & trying to figure something out that may help me before the hot days get here. the truck came with 190 thermo's i put in 180 thermo's wich helped a lot but it stays min 190 to 215. running 40,000lbs up slight hill i have to run fan. was thinking either remove thermo's or putting in 170 or 160 degree thermo's..?????? thanks

Do you have a pyrometer?

Ask a competent shop to connect to the ecm and check the injector calibration codes. If they are all set the same, you've found your problem.

If not, i might recommend pulling the fuel return restricted fitting to see if it's been tampered with.

Bob

[allan5oh]

What do calibration codes do exactly?

[Bandit102]

Yeah, Bob, could you elaborate some...This CAT I'm driving right now (I made a post about it under bad kitty cat) doesn't get hot, but you mentioned Pyro - this one will go to 1400 at around 1300rpm and is getting horrible fuel mileage. It has a recent turbo, new CAC and new hoses on it...

[heavyhaulerss]

Do you have a pyrometer?

Ask a competent shop to connect to the ecm and check the injector calibration codes. If they are all set the same, you've found your problem.

If not, i might recommend pulling the fuel return restricted fitting to see if it's been tampered with.

i have no pyro meter. however i am schedualing a day to have injectors put in since they have over 1.1 mil miles on them. with the exception of one that i had put in a year or so ago. also as others here... the injection calibration codes means what & how does the codes affect the temp ?? thank you.

[bob h]

What do calibration codes do exactly?

...an electronic fine tuning of the EUIs

[allan5oh]

Injector timing?

[pdm]

Its not timing, its fuel delivery. it fine tunes very small differences in fuel delivered by the injector. Over thousands of injector strokes they won't all deliver exactly the same amount of fuel. The trim codes help adjust for that. The ecm will fire the injector slightly longer or shorter to compensate. Hope this helps, i'm not the best at explaining things sometimes.

[heavyhaulerss]

all new injectors installed. still water temp running higher than normal. shop mgr said could be air to air prob, but did not elaborate??? other than trying a new water pump. i'm out of idea's. last water pump put on 2 years ago. new rad, recent, all new hoses,thermos e.t.c. what should i look for on my air to air. also had air coller leak tested. it's o.k.

[Part Time Dweller]

shop mgr said could be air to air prob, but did not elaborate???

That would be the charge air cooler he is referring to. This is up in front of the radiator, it cools the air that comes out of the turbo before it goes into the intake.

If it, or any of the piping have a leak, then the air going into the engine isn't getting cooled enough and will make the engine run hot. You will especially notice this on a grade. If you had a pyrometer, you would be able to tell if this is the problem,as your exhaust and coolant temp will rise together more than they should.

The best thing to do is have the charge air cooler and the plumbing pressure tested. With a million+ miles on the truck, it is quite possible that this could be the problem.

[heavyhaulerss]

yes that is when it gets hot quick. going up a grade. i have no pyrometer though. will have it checkedd out thank you

[heavyhaulerss]

is there a way for me to check my self for leaks? when i had new rad put in, the air cooler was checked & found no leaks. so i guess it will have to be elswhere in the sys. most shops around here want you to make an appoint & then keep your truck for a couple day's.

[Part Time Dweller]

If you think the cooler is good, then check all the rubber connecting tubes and clamps on the system. There should be 3-4" piping that comes out of the turbo, to one side of the cooler, then out the other side to the intake on the engine. Look for loose clamps and bad connectors..

As far as the cooler itself, you would need to disconnect it then block off one end and pressurize the other. DO NOT put more than 10- 15 lbs of pressure in it. If you can figure a way to do this, then spray around the cooler with soapy water and look for bubbles. If you take it to a shop, they have two caps they clamp on, one is sealed, the other has an air fitting with a gauge and a shutoff so they can put air in it and see how much pressure it is loosing and how long it takes.

[duck]

Do you have any logged ECM codes? You could have a crap sensor telling the ECM it is much warmer than it is actually. ECM then kicks on the fan and the gauge reads what the crap sensor is reading with actual temp low. Also make sure all the road debris and crap is steamed out of the ATA and rad. I don't mean blown out with a hose but remove the ATA and use hot pressurized water - you would be amazed at the amount of crud inbetween the fins after winter.

[pdm]

Do you do oil samples? If not it would be a good idea to take one....

[heavyhaulerss]

[quote]Do you do oil samples? If not it would be a good idea to take one...


what can this have to do with temp ? I was also thinking about the air to air... if there is a leak in the air to air wouldnt there be a noticable decrease in power? I replaced the 2 air to air hoses just this wknd because they were on truck since I bought it. I remember a clamp breaking one time years ago on a air to air hose going to the turbo side & it lost over 60 % of it's power. I also thought about putting on new water pump. though i'm not sure if it would help. it does not leak. wondering if something else could fail on water pump to cause temp to rise. if i am idleing temp will go from 170 to 195 in less than 5 min. no water loss.. water pump has approx 300.000 mi on it. the 170 thermo's help a lot, but it's not what should be in there.