Cooling problem

[Cyberbeer]

I'm starting to get a little frustrated with this truck. Two weeks ago I replaced a leaky heater core. Five days later the truck started to get hot but only after about 35-40 minutes of driving (speeds of 45-55mph), I never let it get upto the H, but it did get into the O. So i started hunting for leaks...found one on the overflow bottle, and the thermo housing was missing its gasket. Replaced the overflow and put a gasket on the housing yesterday.

Drove the truck to college today and it everything was fine until I hit that damn 40 min mark and it started to get hot again. So I pulled over checked the coolant level which turned out to be fine. So let it cool down from O to M and drove it the rest of the way. It hit the O again right before parking, so I decided to try an experiment and just sat there and let it idle for 10 minutes. By the end of that time the temp had stabilized right between the R and M.

So I am stuck, drive it longer then 30 mins it starts getting hot, stop and simply idle it begins to go down. The thermostat is only 3 weeks old, fresh coolant, new heater core, new hoses, new rad cap, new overflow bottle, and new thermo housing gasket. Any ideas?

 

[Wicked_Sludge]

worn water pump impeller or clogged radiator...id suspect the water pump first.

 

[Cyberbeer]

I would too, however the rad is the same one from the old motor that had a cracked head. Gonna flush it out 2morrow and see if that helps. Otherwise gonna have to drop 152 on a new rad.

 

[Wicked_Sludge]

before you buy a new radiator, check/replace your water pump. the pump is only $30 and theres a high probability that its the source of your problem.

 

[holyford86]

have you checked to see what the actual temperature is via mechanical gauge? 195-200* is where it should be when its fully warmed. Your gauge could just be messed up. Or the thermostat could be of too low of a rating or stuck open.

 

[Cyberbeer]

No I havent checked with a mechanical gauge, dont have one. The thermo is a 192 and is only 3 weeks old. As far as I know the water pump is only a year old..meh guess I will take it off and take a gander at it. Thanks for the tips will update in a few hours...hehe early riser

 

[Beastly88]

Holyford is right cause i can drive my truck over 40min and the gauge never leaves the c at the bottom ..

 

[cocoasranger]

The highest mine got in summer was to the N in NORMAL. Now that's just not normal. The stock temp gauge sucks almost as much as the stock oil gauge.

 

[Cyberbeer]

lol, atleast you have an oil gauge, all I got was an idiot light. Took of the WP and checked it over..its fine. Flushed the cooling system and it was gross...during flush found a leak in the rad, so had to replace it anyway.

Let you know if this fixed it soon as I drive it a bit.

 

[Cyberbeer]

Well found yet another problem today concerning my cooling system. Went out to inspect for leaks and the such. I was looking at the top of the motor on the passengers side and I find coolant under ontop of the intake manifold. There are crevices I guess where the plenum arms come down and mate to the manifold, and all 3 of the "crevices" are full of coolant. I checked the drivers side and saw none.

This is really starting to frustrate me. Does this sound like a leaky intake mani gasket, or cracked head or gasket.

EDIT: False alarm seems the heater hose was leaking a bit and the coolant ran along the valve cover to where I found it.

 

[Tedybear]

lol, atleast you have an oil gauge, all I got was an idiot light. Took of the WP and checked it over..its fine. Flushed the cooling system and it was gross...during flush found a leak in the rad, so had to replace it anyway.

Let you know if this fixed it soon as I drive it a bit.

Guess again LOL!!.

That gauge setup is as phony as it gets. Short history of ford and their oil pressure gauges: Ford used to run normal oil pressure gauges, but people got paranoid due to the natural fact that as the engine gets warmer? Oil thins out a bit and the pressure drops. combine that with in town driving? And the oil pressure will go low....drive it faster.....pressure goes up. Simple enough, but the average idiot thinks it's "just not right" and a lot of people complained.

So Ford uses a neat looking gauge, that reads mid-range about 90% of the time no matter what. Ours does kick up slightly when driving at higher speeds...but at a stop sign? it's still pegged dead center. I've got a SunTune oil pressure gauge "T" fitted into the system. So both gauges are functional. The mechanical gauge floats all over the place as expected while driving....The factory one? Doesn't budge below that middle mark. (even when the mechanical gauge floats around 15lbs of pressure at a stop light after driving 50 miles...The factory one? Still states the pressure is mid-range)

I did this "T-In" trick due to having the gauge bottom out a few times when the truck's idle kicked to low at a stop light. (it bottomed at 350rpm...barely enough to run) The factory gauge went totally to "zero"...but I was watching it on the mechanical gauge and figured out exactly the cause and effect.

S-