Engine Cooling - Worthwhile responses only please

[Chadnutz]

For about 3.5 years now my water gauge has been reading higher than it did when I first got the truck. Not only does it read higher, but it gets higher and lower with any change in conditions. It never used to move around, and all other cars I have driven in have guages that stay in one spot no matter what condition they are in.

I have 2 electric fans that blow a lot of air.
Thermostat - 195 deg (correct, new)
Radiator Cap = 13 psi (correct)
No leaks
Full of water
New sending unit
Slightly corroded wire connecting to sending unit very loosely.
Did not lower radiator when put on body lift which puts it 3" higher relative to the motor as was before. Did not notice chang in guage until 6 months after body lift.

Symptoms -
Runs "hotter" on the highway (higher RPMs)
Runs "hotter" on hot days
Passenger side fan blows barely warm air, drivers side blows hot air. Radiator possible clogged (~4 years old) Water comes in top of passenger side, leaves bottom of drivers side.

Please help. I have been dealing with this problem for 4 years now. No one has been able to diagnose it. I don't know if it is the gauge or if it is actually running warm. I put an aftermarket gauge in the upper radiator hose and it reads 230 to 240 which seems pretty hot, although water does not boil over into the reservoir at this "temp". The factory gauge reads close to the top of normal where is used to read about 1/3 of the way up from the bottom of normal.
Heater blows air over 200 degrees using turkey thermometer in the vent. Is this normal??

[robertf03]

i'd get the radiator checked out, you just rebuilt that engine right? the engine went out in my dad's land rover and it overheated like crazy with the new engine until we had the radiator rodded.

You've got that smitty built bumper on the front right? do you think it started overheating when you put that on? Sometimes blocking any part of the radiator even with a small bumper can cause it to over heat, but I'd check the radiator first.

[Krawler68]

prolly the radiator... has the truck overheated yet? have you had to actually stop the truck to get it to cool down? pull over or anything? I say put some tape over the gauge and drive it until steam comes out of the hood...

[StevenAg03]

it might have a lot to do with the body lift and not moving the radiator. when they put the body lift on my truck, instead of moving the radiator and fan shroud, they just cut the bottom part of the shroud off. since then it runs a little bit hotter. however mine still uses the motor driven fan and not an electric fan.

i would take it and have the radiator flushed if i was you

[Chadnutz]

I "flushed" the radiator once with some Prestone crap. It did not do anything. Upon checking again I found that both fans are blowing hot air. I have also put a water hose in the top and water came out the bottom just as fast as it had gone in. What is a good lifetime for a radiator?

[Chadnutz]

Doug, I'm not risking my aluminum head to see where the gauge is when the motor boils over. I have already changed head gasket twice. Once when I thought it was leaking but it was a hose way up under the intake manifold, and once because I didn't clean off the head surface enough or buy new "stretching" $10/each head bolts the first time around.

[robertf03]

i flushed the land rover with that same preston crap, tried water wetter, and got the flush kit where you cut a hose and hook up the garden hose

none of that helped at all, take it to a radiator shop and have it rodded

[Broncocustom]

Take it to Bryan Radiators. They do good work that will not cost you alot. They cleaned the broncos radiator and welded the entire top back on for $20.

[mark]

You can find out if the radiator is partially clogged by getting the truck good and hot. Then spray the front of the radiator with a hose. The sections of the radiator that work will evaporate the water quickly. The ones that are clogged will be much slower to evaporate the H2O. Either way, you'll know whats working.

When you spray the radiator, you should also see the engine temp come back down to the normal range if it is a radiator problem. Water cools more efficiently than air.

After that all that is left is the water pump.

BTW: One more stupid question. Are you sure that there is no air trapped in the system?

[Chadnutz]

In the several times that I have changed coolant I have let the motor run to operating temperature before putting the cap back on. It should have released all of the air. Is there any way I can check for air in the system?

[Chadnutz]

I also took it to some radiator shop near Bryan Drivetrain about a year ago to have the solder a hole shut in it. I don't remember if they flushed it or not, or if it is standard practice to flush any radiator they work on.

[mark]

Some cooling systems, especially one from the Japs and Brits have areas in which air can be trapped. If so, they will have a plug that can be removed so that all the air can be let out of the system. It is unlikely that this is the case after 3.5 years, but it is something to look for. Check your owners manual for details.

Soldering a hole shut does not require the shop to dip the radiator. In fact some of us can fix hole in a radiator with little more than some Radio Shack solder and a camp stove. If you didn't pay more than $50 bucks, it was not dipped.

-Mark

[Chadnutz]

My dad's friend (full time self employed mechanic) tested for combustion entering the coolant via a cracked head this weekend. You put this plastic thing over the fill spout on the radiator and pull air through this blue liquid from the radiator. If the blue liquid detects CO2 it turns yellow. Well, the thing was designed for a big cap and he was having trouble making a good seal. When he did the liquid started to turn green. Then the coolant expanded and got sucked up into the device. Anyway, the fact of the matter is that it was turning green which could indicate a cracked head.

As soon as I get my moms spare car back - the Cressida I used to have up here which needs a few minor repairs - I will pull the head off and take it to Vilas. I took it to Napa and had it "checked" once before and they said it was fine. This mechanic said they probably didn't check very hard for $25. The mechanics helper said his cousin or friend or someone welds cracks in heads. Mine is aluminum. No guarantees. It is possible? I know a full time fabricator on Riverside campus that owes me some time. If the head is cracked is it worth trying?

It would make sense that I have combustion since the heat goes up with RPMs, even as speed goes up and everything else has been checked.

[stinger7401]

it's very possible that a cracked head would cause this problem but before i pulled the first bolt i'd make 100% sure that it is a cracked head by doing another test except with a little more accuracy. Make sure that if you do pull the head have them magna flux it and check for interal cracks. To have this done it wil run more than just a 25$ visual inspection like napa would do. Also make sure that it is not the radiator. We have seen cars come into our shop (mainly fords though) that are 5-6 years old and are over heating due to leftover casting residue (sand) from the block. This happened on more than one occasion.

On a side note, for everyone, we recieved information about a month ago that it is now recomended that you put distilled water back in you engine instead of just hose water. They say that the calcuim, lime, etc will get into your cooling system and with many of the new aluminum heads and cast blocks the deposits cause bad corrosion between the two.

[BigRedFord04]

About a week ago i put a 4 core radiator on my truck...cost me $40 brand new w/ O'Reilly warranty . Now, even when i forget to turn the electric fans on it doesnt get hot ... only time it did before was in Llano in the sand, we'll see how it does next time.