removing thermostats

He can pick up a few spray cans of "coil cleaner", about $6 a can last time I bought it, at any Lowes or Home Depot. Check with the employees walking around the store and ask if they have anything in spray can for HVAC unit on a home's AC condensors - that you wash out with a water hose - and they should know where it's at. Good practice to do this every couple or 3 months, more often if offroad or in dusty conditions.

 

Removing the thermostats removes the preasure in the block that circulates the coolant at a fast pace to force the coolant around the valves at a high flow rate,
That engine is engineered to run with 190 degree thermostats, period and have a fan out temp of up to 225 degrees.
A proper cooling system needs a coolant filter, a clean system, antifreeze to _45 degrees. I recommend power-cool, then take the truck to a power washer and spray the radiator straight threw, with the fan on and motor at 1500 RPM do the whole rad top to bottom with soap, 3 inch wide pattern. Rinse it, then stand back and watch the spray pattern, then put on the bug screen, do it again, many bug screens are plastic and really restrictive.

 

I'd be leary of power washing it - get too close or crazy and the fins will get bent. A water hose is more than enough pressure if he sprays some coil cleaner in it first.

 

Coolant entering block may not be above opening temp, coolant entering radiator may be well over it.
Oven cleaner and a garden hose works for cleaning.
Pressure washer most likely will close fins causing more problems.
A few drops of dish soap works as water wetter.
Just a few drops, like two or three.
We used this in race cars for many years.
Cheap way out that works
Most trouble come from cooling too fast after heating, 200 to 210 should just make it pull. The engine is designed to run at 190 so that is only a 10 or 20 degree rise.
Older one piece head engines would warp a head unless you kept it warm awhile after a good pull.
Good luck.

 

Has anyone tested the thermostats?
I have thrown a thermostat in a pot off water and then brought it to boil.
Use a temperature gauge to check.
Found it did open at the right temperature but it only opend halfway.

 

Cold/cool/below factory operating temp = maximum/moderate/above normal engine wear also.

One reason for the t-stat is to bring engine up to optimum operating range ASAP.

Removing a t-stat on any vehicle is not a recommended.

 

Bad idea to remove the thermostats. It has nothing to do with slowing the coolant in the block or radiator to pick up or dissipate more heat, that is simply not true. There is always coolant in the block and radiator, so there is always heat transfer, the speed of the coolant does not change the rate of transfer. If you double the speed of the coolant, it is true that it's in the block 1/2 the time and can only absorb about 1/2 the heat. What people who say this over look is that it's flowing through twice as often. Faster flowing coolant is actually better because it helps even out temps. If the coolant flows too slowly, combustion chamber temps go up and liner temps go down. Too fast wastes more power turning the pump than it helps so there is a practical limit.

With all that said, the key to the cooling system is pressure. When you pull the thermostats, you lose pressure in the block. Combustion chamber temps are very high, coolant does boil around them and this is normal. Steam bubbles are very small and normally get carried away by coolant flow and change back to liquid long before exiting the engine. This is call nucleate cooling, normal in most engines. Without sufficient pressure in the block, you lower the boiling temperature and steam bubble can become steam pockets and cause some bad situations. The thermostats act as a restriction to flow and the water pump builds additional pressure over cap pressure.

Water wetter does work, it is really nothing more than anti-foaming soap. It reduces surface tension of water and therefore reduces the size of steam bubbles. In my race car, I was able to run optimum timing without detonation after I added it. Before that, I had to run 2-3 degrees retarded before detonation started setting in. I use it in all my vehicles.

Everything that's been posted about engine wear is correct, too cool is bad for engine wear and fuel economy. I think you have another issue causing your issues. Make sure the radiator is clean and do a cooling system flush.

 

On my M11 I drilled 2 x 1/8 holes into the thermostat (holes 180 degrees apart) worked well here in oz. still allow engine to reach good operating temp in short timeframe. And running temps stayed within cummins specs.