1978 Ford Van overheating

NORTHSTAR

MEMBER
1978 FORD E-SERIES VAN

I have a 1978 Ford, E-150, v6 ; mileage 177000
Has been well taken care, original paint, almost in mint.
That I got from the original owner, 7 months ago.
I toke the van on a roadtrip(800 miles), got to my destination, everything was fine. Gave an oil change (10w40) before coming home. About 550 miles in to the trip home, as I was entering the mtns.(Going up). The engine gauge started going up and the oil presure gauge went up also(that day was really hot). So, I stop for 45 minutes for a brake. Started the van up again and drive a mile till both gauge where in the dangerous level. Stayed over-night for things to cool off, checked all fuilds in the morning, all were full and after starting, gauges were good. Finished the trip home with a few extra stops when the gauges would go past the norm.
I have driven it a little here, and the engine and oil gauges will go up for a few minutes and then go back to the normal spot.
I found out that the original owner switched from 10w40 to 15-40 five year ago(15,000 miles ago).
Could this just be because of a different oil, and why would the oil presure go up if the engine gets hot. Shouldn't the oil presure go down when the engine gets hot.
2 rows in the radiator.
vacuum is at 18in. At idle.
Thank you for your time.

2 Replies

HIPPO800

MEMBER
29 POSTS

I'm not an expert but I do have a Ford van.
How many rows in the radiator?
If temps are a problem try adding an aftermarket oil cooler.
Are the valves adjusted too tight?
Vacuum should be @ 21in. At idle.
How about installing a temp sensor on the radiator.
How do you know the guages are accurate?
A 10W30 full synthetic should be all you need in the 6, unless you are racing at 100 mph, and even then 10W30 is satisfactory.
If there are no blockages in the cooling/heater components, perhaps a stuck thermostat is indicated, but this would be a steamy situation.
If the engine is mechanically healthy, then go to extra cooling, with a 3 or 4 row rad.
Valve preload should be in the low thousandths.
Anyway, overheating is unusual indeed.
Will the 1985 pedestal rocker head fit on the 77 4.9 block.
I am not aware that a 77 Ford van had a v6.
Hmmn.