heat issue

Joined
Apr 15, 2009
Messages
211
Likes
0
Points
16
#16
yes coolant is full and vehicle is stock engine wise and jd i would think 140 is good as well but it has a 195 t-stat and anyone else i talk to that has one of these trucks says their temp gauge runs about mid way with great heat i took pic after long road trip today of temp gauge and that seems to be the best it gets
 

Attachments

billr

wrench
Staff member
Joined
Mar 12, 2007
Messages
6,076
Likes
62
Points
48
#17
We are sure wandering in the weeds here! Stick a cheap cooking thermometer into the coolant and let's get past any wonderment about what the coolant temp is.
 
Joined
Mar 1, 2002
Messages
3,409
Likes
44
Points
48
Location
Kentucky
#19
Is the plan to "remove radiator cap, put thermometer into coolant"? Might be tough to get a good reading in cold weather with a radiator of this design. I think that truck uses a belt driven fan that pulls air thru the radiator, even if the fan clutch is "disengaged". So, I would expect a (hard to estimate) heat loss between coolant entry point and contact with the thermometer.
 
Last edited:
Joined
Apr 15, 2009
Messages
211
Likes
0
Points
16
#20
yes it is run off the water pump by the serpentine belt i have not been able to get a thermometer yet and in order to get what heat i get i have to keep the rpm's up luckily its a 5 spd manual so i can run in 4th where i normally would 5th but even still i can't run the heater fan on full orit cools offmain things i have even seen cause it are weak water pump and heater core truck is somewhat a work in progress as i think it sat for 3 or 4 years before i bought it
 
Joined
Mar 1, 2002
Messages
3,409
Likes
44
Points
48
Location
Kentucky
#21
Well, pinching off the upper hose would only require some very basic equipment. If you had two wooden sticks and some wire, it could be done. Putting cardboard on front of the radiator would be another diagnostic route, but pinching the hose would be more definite.
 

oddone1975

Sr. Member
Joined
Apr 15, 2009
Messages
211
Likes
0
Points
16
#22
I went and bought a meat thermometer today and checked coolant it's getting to 110°F by that at radiator then dropped to like 80° not sure what is going on if I have rpm around 2k it blows ok heat
 

oddone1975

Sr. Member
Joined
Apr 15, 2009
Messages
211
Likes
0
Points
16
#23
I did the 30sec at like 2k rpm and checked with thermometer and it got to almost 130° at radiator then dropped but both heater lines were rather warm not overly hot but above warm
 

oddone1975

Sr. Member
Joined
Apr 15, 2009
Messages
211
Likes
0
Points
16
#25
Yes I talked to my mechanic friend and he had a customer deal with same issue his was vaper lock
 

billr

wrench
Staff member
Joined
Mar 12, 2007
Messages
6,076
Likes
62
Points
48
#25
"Yes", the thermometer was immersed in the coolant; or "yes", I talked to my mechanic?

That "vapor lock" theory is full of, well... gas. There is always vapor in a cooling system. That's the whole point of pressure-caps on cooling systems, to raise the vapor pressure from the sea-level atmospheric 212F to something higher. Automotive coolant pumps are almost always down low enough that they are flooded with coolant as long as coolant level is anywhere near normal. I suspect your mechanic meant an "air lock" that can cause hot spots in the cooling system. But, that isn't your problem at all is it? You can't get it up to heat.

I still am convinced that the only way you can over-cool is a bad t-stat or plumbing that has, somehow, bypassed the t-stat. Every other kind of problem causes over-heating.
 

oddone1975

Sr. Member
Joined
Apr 15, 2009
Messages
211
Likes
0
Points
16
#26
Yes the thermometer was fully in the coolant. And nothing has been bypassed in the cooling system the thermostat is right in with the upper radiator hose
 
Joined
Mar 1, 2002
Messages
3,409
Likes
44
Points
48
Location
Kentucky
#27
I am going to have to recommend my previous suggestion. Pinch upper radiator hose and see how the heater works when the engine temp gauge reaches midpoint.
 

oddone1975

Sr. Member
Joined
Apr 15, 2009
Messages
211
Likes
0
Points
16
#28
I will see if I can get what is needed to do that too but my mechanic found this out that these engines tend to get a pocket of trapped air by the thermostat neck as he talked to someone who had same issue I have and was throwing part after part at it until supposedly another shop found the problem was trapped air and had to drain the cooling system,fill like half way,let it run a while then slowly add more coolant this is just what I heard the guy tell him and he said it solved the issue for him sounds strange to me as well as I always thought with normal radiator that has cap on it you just had to burp it a little as heat line comes directly off water pump. I did one thing tonight when I stopped to help someone broke down is I held it at like 1500 rpm (, estimate as I have no tach in this truck but yet and auto trans does) and it got nice and warm in truck but under normal circumstances it doesn't.
I'll see if I can find a couple small boards to go either side of upper hose and clamp it and see if it makes any difference
 

oddone1975

Sr. Member
Joined
Apr 15, 2009
Messages
211
Likes
0
Points
16
#29
Ok took today and swapped hoses at heater core to reverse flow through to possibly purge and minor blockage and stuff a large sheet of cardboard in front of radiator and at idle still get squat for heat if I bring rpm up around 3,000 it gets warmer coolant temp still not above 150° and gauge still not even close to mid way
 

Attachments

billr

wrench
Staff member
Joined
Mar 12, 2007
Messages
6,076
Likes
62
Points
48
#30
Are you accepting that the engine is not getting up to normal temp? With that condition the heater can never work properly and you are just wasting time fussing with it and its hoses. If you don't believe the temp is way low, say so and I will butt-out; any further discussion is a waste of my time.

If you do believe that engine temp is low, then put the clamp on the upper hose that Dan suggested. That will act as a manual t-stat and probably heat the engine up and confirm that this is simply a matter of a bad t-stat.