Bronco Forum - Full Size Ford Bronco Forum banner

1 - 10 of 10 Posts

·
Registered
Joined
·
37 Posts
Discussion Starter #1
My '88 4.9 5 speed 4x4 f150 is starting to overheat..it does it when cruising at slow speed (like on any trail) and when sitting idling..I don't seem to be loosing fluid at all..I've been checking it every few days when its cold and its at the same level.

It runs in the middle of the gauge when cruising at higher speeds like 40+. Also..if its starting to overheat and I give it the mustard through a few gears it will cool down and run at the right temp.
I will be grateful if its not the headgasket..i hope it isn't.

Thermostat?
Water pump?
Electric fan swap?
 

·
fishin' without dad
Joined
·
1,069 Posts
It sounds like the fan clutch is shot. Not engaging when it should and when you speed up you are forcing more air in order to cool things a bit.


my $.02
 

·
Registered
Joined
·
2,785 Posts
I'd park the thing till I fixed the problem. I saved warping a head by using the heater, but I blew the head gaskets when I had a car overheating.
 

·
OUT OF BUSINESS / M.I.A
Joined
·
4,659 Posts
And spend an hour of your life and $21.00 and install a REAL temp gauge. The one you're looking at on the dash is as about as useful as a fricken football bat..........
 

·
Registered
Joined
·
37 Posts
Discussion Starter #5
It sounds like the fan clutch is shot. Not engaging when it should and when you speed up you are forcing more air in order to cool things a bit.


my $.02
Yeah..now that you say that I just kinda realized the fan doesn't really make that loud WHURRR sound if i hit it in neutral..Might be time to do an electric fan swap.

And yeah..I don't really let it get over 3/4 hot..I will shut the motor off for alittle while. Its really only noticable when i'm driving around town through traffic for awhile when its hot outside..or cruising on a trail when its hot..I want to get this fixed as soon as possible but its not a problem usually on the roads I drive on.
 

·
Registered
Joined
·
37 Posts
Discussion Starter #6
And spend an hour of your life and $21.00 and install a REAL temp gauge. The one you're looking at on the dash is as about as useful as a fricken football bat..........
Hmn..never thought of that..The gas gauge and the oil pressure gauge don't really work and my oil pressure gauge shows bottomed out low, and the Engine light is on. But my aftermarket oil pressure gauge reads right where it should be..around 40psi when running. Might have to check that out.
 

·
fishin' without dad
Joined
·
1,069 Posts
I am getting ready to install mechanical oil pressure, "water" temp, and tranny temp(along with a remote tranny filter).


The only thing holding me back is money. Oh yeah....and time.
 

·
Kitteh Commandaar!
Joined
·
4,194 Posts
Check the fan clutch. You should be able to turn it by hand when it's cool, but it will have some resistance, but not to much. After a drive at lower speeds, stop the truck and check the fan again. It should be much more resistant to turn when it's warmed up (clutch locks up when hot). IF it feels very similar, then the clutch is probably toast. Average 70 bucks to replace...

Mine failed in locked up mode...sounded like a little airplane going down the road.

As for the gauges in those years, maybe even still now, they where still basically idiot lights...useless.

KC
 

·
Registered
Joined
·
37 Posts
Discussion Starter #9
Well..confirmed today that the fan clutch is shot..no difference from when I checked it when it was stone cold this morning and when I checked 4 hours later after driving around.

Also..I drained a few quarts of coolant out of the radiator today and replaced it with 100% water..the fluid antifreeze mix that was in the radiator was really thick..i'm begining to think that whoever filled this thing up last time used 100% antifreeze and not a 50/50..water obviously cools much better because I drove all around today, let it sit and idle and cruised around trails and it didn't ONCE get over the 1/2 way mark..I guess maybe I should test the coolant with one of those things.

Oh yeah..and sense the fan clutch is bad i'm gonna start gathering parts for an e-fan swap.
 

·
Registered
Joined
·
2,785 Posts
I guess maybe I should test the coolant with one of those things.
I would be inclined to myself, if you don't know whats in your system. I actually dumped the normal fluids out, and changed them when I bought mine, aside from powersteering fluid and brake fluid etc...
 
1 - 10 of 10 Posts
Top