tried everything, still overheating.

[Pallo_r]

Have checked for insufficient coolant in the system. Have changed water pump and drive belt. Changed old radiator for a new radiator. Changed faulty thermostat many times. Checked for broken or cracked fan blades. Had radiator cap checked for maintaining proper pressure. Discovered cracked heads, rebuilt. Lost heater core while back, bypassed. Flushed system after rebuild. So very lost, and have put a lot of money in a 500 dollar truck.

This is a 2.9 engine in an 88 Ford Ranger, 2WD. I have two questions, could bypassed heater core be the cause of overheating? or how about a faulty Catalytic converter, as it didn't pass smog here in California?

 

[Tedybear]

Does the truck overheat when going down the highway, or when in town at slow speeds or stop and go traffic?

S-

 

[RonD]

Cat converter....no, it wouldn't cause engine over heating

By-passed heater core....no, as long as it is by-passed and not blocked off, i.e. the two heater hoses are connected together not just plugged.

What's the current status of the temp?
Does it run warm or overheat to HOT on the gauge?

Does the overflow tank fill up and overflow or constantly bubble, even before engine gets warmed up?

On a cold engine you can remove rad cap and put a latex glove over the cap opening, use a rubber band to hold it on the opening, or use a balloon on the cap opening.
Remove overflow hose, and plug that opening, vacuum cap or short hose with bolt in it, works fine.

Remove coil wire, so engine won't start.
Turn over engine and watch the glove, if it moves/inflates then you still have a head gasket leak.

 

[Pallo_r]

overheats while sitting (15 mins), while driving on even surface, going up hill, going down hill. frusterated

 

[Tedybear]

overheats while sitting (15 mins), while driving on even surface, going up hill, going down hill. frusterated

Let me put this another way.

When you are going down the highway at 50-60 MPH. Does the truck over heat then? Or does it stay within range.

One overlooked problem that does happen (and I'm known for pulling the oddball problems out of my hat) Is the fan clutch that these engines used. If the clutch isn't doing it's job? Then at low speeds (in town and stop/go driving) you will see a marked increase in engine temp. Where as going down the highway? You have a lot of "Ram Air" blowing through the rad.

Everything that Ron stated? Is quite possible! But when I see a lot of overheating threads? I rarely see the clutch on the fan mentioned as a possible issue.

S-

 

[aspevacek]

The question still has not been answered if the thing is pissing fluid out when it over heats or if the OP is going off a high gauge reading to say it is over heating?

Also I see no mention of the Fan Clutch being replaced

Anther question is how bad did it fail on the emissions test? Where the numbers border line or what? Show us the numbers from the failure. It could be something as simple as a tune up keeping you from passing.

 

[Finnigan]

I have an 86 2.3. I don't know if you have the same radiator I do but I believe I have found a problem on mine werer if I turn the radiator cap closed as far as it can go the arrow on the cap for the overflow hose does NOT actually line up with the hose. I have found my truck with an empty overflow and the radiator low on coolant. I believe (not 100% positive) that if the arrow is not lined up with the hose it does not function properly. If I turn my cap loose to where the arrow lines up it is in the position just before I would have to push down on it and turn to take it off. With the arrow lined up it does not seem to loose coolant.

Also, did you replace your hoses when you changed the radiator. Old hoses can suck closed and inhibit coolant flow.

Also, is your oil low? Do you have sufficient oil pressure?

 

[naford]

Not to thread jack. Could you take a box fan and tyrap it to the front of the truck so it bows air through the radiator. Would it be enough air to keep it cool? Obviously you would have to be stationary.

 

[GentleRF]

Thinking outside the box for a moment, what about the radiator pressure cap? I seem to recall a case of a Falcon overheating in much the same way. Owner of said vehicle went to the parts house and the grizzled looking parts guy gave him a 15 lb cap to replace the 13 lb original Ford one. Never had a case of overheating again.

Lowering the pressure, as one poster suggested, is not a sure way to reduce overheating. There's a reason Ford put the stops on the radiator cap mount point.

Rick in East Bremerton

 

[Finnigan]

Lowering the pressure, as one poster suggested, is not a sure way to reduce overheating. There's a reason Ford put the stops on the radiator cap mount point.

Rick in East Bremerton

I'm not sure if this was in reference to my post, but I'm not suggesting he doesn't use the stops. In fact I WANT him to use the stops.

Let me put it this way. If I tighten my cap all the way to the right the vent arrow does not line up with the vent tube. It coes past it. If I then turn my cap the the left to rest against the stops the arrow lines up with the vent. From here, to remove it, I would then have to push down to clear the stops.

Basically I'm saying make the arrow line up with the tube. Even if you can turn it farther to the right, don't.

 

[GentleRF]

I hear what you are saying about the arrow but have not ever followed that advice due to the aspect of not seeing any arrow based opening or obstruction on any of the radiator caps I have ever bought. Stant and AC Delco are two of the major brands. Balkamp is another brand. Have you seen such an instruction? I'd like to know since it would show I've been doing it wrong for decades.

Rick in East Bremerton,
Under the hoods of vehicles since 1963

 

[Finnigan]

I only see the instruction written on the cap itself. "align arrow with vent tube" or some such without actually looking at it. I'm in the same boat you are. I've been tightening it right down for a couple decades. This time, it seems, if I do tighten it right down the overflow system does not function properly and I end up with an empty overflow and a short radiator. If I line the arrow up with the tube I don't seem to loose any coolant.

 

[4.0B2]

to the OP..
pressure check your system again.
check your radiator cap again.
if you're system is not pressurized, it'll over head.
replace your fan clutch. not just check the fan.
make sure you have 50/50 antifreeze/water (or close to it).
make sure you bypassed the heater core NOT by just blocking off the hoses.
what thermostat are you using? don't NOT use a thermostat b/c then the water flows to quick and doesn't have time to cool down in the radiator (in some cases).


if it's heating up when idling, I would say waterpump, fan clutch, or thermostat is bad. Start with the fan clutch since the others have been replaced.

 

[killj0y]

Yea if its overheating 15 min into idling sounds like a bad pump or fan. I would go with the fan. He could try pouring room temp water over the rad when it is getting too hot to see if the rad is working and water is flowing. Aside from that if he went through the trouble of doing everything he says he did, I would just do the fan clutch or at least check it out and get a new rad cap. He hasn't mentioned any coolant loss so I wonder if he isn't losing coolant somewhere...