new here, have an '86 f-150 with a 300 in-line six and 4 speed manual tranny, here's my preblem. occasionally, especially when driving distances, the truck's temperature and oil pressure will both get extremely high. basically to the point of overheating. usually i think that it is just another thermostat sticking closed, but i think it does it even when i take the thermostat out. for about the past year i just go ahead and take it out come summertime. i know I'm not supposed to, but what other choice do I have, it will overheat and the oil pressure will go through the roof. any help would be greatly appreciated. almost forget, this is second motor for this truck, it has done it with both motors, and i think nearly all the emission equipment has been removed. thanks!!!!!!!!

 

Checked your fan clutch and had your radiator flow checked?

 

add an oil cooler or 2! or re-locate your filter. both should help! also try flushing the cooling system out....they sell kits for like 5 or 6 bucks.

-cutts-

 

Also, if it's overheating, your oil pressure should go *down*, not up.

 

Is the engine really getting overheated or is the voltage to your guages incorrect.
Remember, electrical gauges, especially old Ford, are not reliable indicators.
Replace the temp and oil pressure guages and get a better idea what is going on.

There is a voltage regulator in the instrument cluster that could be the problem.
Even after replacing that, I wouldn't trust the factory guages though.

After 18 years, you can't expect that those guages are still working accurately.

 

when i did the motor swap, i put on a new fan clutch and a new two tank radiator, and i have also put a new oil pressure sending unit on the motor. i think my next step is putting after market gauges on it. it also has a problem with dieseling. so who knows

 

I'm going to go out on a major limb here but after all that you mentioned dieseling, that changes the whole deal. I've had motors before that were just out of time enough to diesel but ran good that did run slightly hotter. With the dieseling thrown in, could it be a timing issue as well?

 

i haven't had the timing checked since it was adjusted with the motor swap. not sure where it is supposed to be set at? pretty sure i have a timing light somewhere, does anyone know where it is supposed to be set at?

 

Timing would make sense with the dieseling issue. I'd still do the after market guages if you haven't. Hate to rely on the old electrical system for accurate readings.
Make sure you follow the instructions for timing.
With the TFI / EEC-IV, you have to pull the jumper off of the spout connector to set base time. Some don't realize this. I'm not sure which system you have.

 

Imadore, not sure which system that I have either, it's just the carbuerated inline six cylinder with a 4 speed manual tranny. please elaborate.

 

I've heard about that spout before. what exctly is it?

 

Sorry guys I have to do this. I know where the spout is. I'm a little teapot short and stout, here is my handle and here's my spout. LOL. Forgive me.

 

My Camaro had that problem. I tried everything and abything. Finally got a wild notion, after years, to change the fan clutch AGAIN.

I'll be dammed it that didn't fix it.

 

Oops, hit the button too quick. The engine now runs 40 degrees cooler on the highway!