Over cooling

[Decker]

I've got an issue with my 94 Ranger 2.3 5spd. The truck never heats up according to the gauge (I know, it's inacurate). I went so far as to remove the clutch fan last night and ran it for 20 mins before it registered 1/3 up the gauge and had pressure and heat in both hoses. I stopped after that as I didn't want to overheat it.

I have read lots of threads here, but most indicate they do not get heat out of the heater, and I do. I've also read where it could be air in the cooling system, so I popped the cap to the first click and drove for 5 miles to burp it, that did not help.

I'm at a loss as to the problem with this truck. I want to get it running out of closed loop mode so I can get better economy.

Symptoms:
Heat out of heater
No pressure in cooling system
Top radiator hose warm, but not HOT
Bottom radiator hose cool, but not cold
Cap removed after parking, I am able to stick my finger in the coolant. I'd say it's no more then 120 degrees most of the time.

Parts replaced due to failure or routine maintenance:

Plugs
Wires
Coolant
Air Filter
O2 Sensor (stock replacement)
Radiator cap (13 lb stock type, twice)
Thermostat (Failsafe brand, 192* stock temp)
Water temp sensor (the one in the heater hose)
Water temp switch (the one in the block below the oil pressure sensor)
EGR gasket (jacktard P.O. used a Dr. Pepper can as a block off, which blew through 1/2 of it)
Exhaust system from header back (No cat(its on order) -> flowmaster 40 -> nutin. 2" pipe)

Cleaned as part of routine maintenance:

Fuel system - 1 can of Seafoam in the tank
Cooling system - Backflushed with at home kit
Throttle body - cleaned with TB cleaner & towel
MAF - Disassembled and cleaned with MAF cleaner

Any ideas are helpful

 

[jason_mcallister]

I also have the 94 2.3, 5-speed. It is cold blooded due to the oversized radiator. I removed the belt driven fan a few years back and as a daily driver from Olympia to Fort Lewis, it has never overheated on me. The only thing I would worry about is being stuck in one of those famous I-5 traffic jams in the middle of July. If you live in a cold climate, just remove the fan, you'll be fine I'm sure.

 

[Moreflying]

The thermostat regulates the operating temp. You may have a thermostat stuck in the open position or a thermostat that is 180 or lower to open. 195 is oem temp. Looks like you have that correct

 

[rcwc28]

I also have the 94 2.3, 5-speed. It is cold blooded due to the oversized radiator. I removed the belt driven fan a few years back and as a daily driver from Olympia to Fort Lewis, it has never overheated on me. The only thing I would worry about is being stuck in one of those famous I-5 traffic jams in the middle of July. If you live in a cold climate, just remove the fan, you'll be fine I'm sure.

hey try putting a peaice of card board in front of the radiator but NOT over the whole thing just enough to restrict the air flow they do it with semi truck why not a ranger ive donr it in my bronc 2 when i had it

 

[7.5L_STX]

hey try putting a peaice of card board in front of the radiator but NOT over the whole thing just enough to restrict the air flow they do it with semi truck why not a ranger ive donr it in my bronc 2 when i had it

i do that every winter. helps tremendously when your freezing your balls off in the morning.

 

[Earl43P]

I also have the 94 2.3, 5-speed. It is cold blooded due to the oversized radiator. I removed the belt driven fan a few years back and as a daily driver from Olympia to Fort Lewis, it has never overheated on me. The only thing I would worry about is being stuck in one of those famous I-5 traffic jams in the middle of July. If you live in a cold climate, just remove the fan, you'll be fine I'm sure.

I have a coworker who also runs no fan in the NC winter and this is his second 2.3 truck that he's done that with. I'm glad to hear you report a similar "solution". He occasionally has to regulate temp with the heater fan at stop lights after a highway run. He puts the fan back on in the Spring.

With that said, I picked up a 2000 2.5 5 speed from another coworker a couple weeks ago. Being anal, I have the ScangageII hooked up and watch the coolant temp (my fan is intact and its thermoclutch engages for a very short period at cold start, even in this heat - you can hear the brief roar/subside).

I believe it has an aftermarket 193 degree thermostat installed (per the PO). It consistently indicates just shy of 1/2 of the factory gage deflection and the Scangage reports that temp as 181-185. Even after a high speed highway run (I'm talking 70-75mph) and coming to a complete stop with the air conditioning on, it has never climbed over 185 that I have seen.

Mine goes into closed loop somewhere in the 130's. I'll try to watch it more closely.

I suggest the OP replace the ECTS (Computer's 2 wire coolant temp sender) and ANOTHER thermostat if it isn't getting into Closed Loop. How do you even KNOW that on an OBD1?

I intend to put another 193 -195 T-stat in this truck before next winter.
I've considered blocking off part of the radiator to see if the increased coolant temp will net me better MPG. My 4 mile commute doesn't really lend itself to that, but I did just take it 200 miles away last weekend and only got 22 mpg. But I did put 235/65-16" tires on it to replace the 215-75-15s that the PO had (door sticker listed 225-70-15), so they are wider and heavier. I had an empty set of better looking rims on hand so I went for the wider tread.

 

[v8318cid]

I don't know what year it changed, but the 2.3 litre in the early 90's had a cast iron thermostat housing that would rust over time. It had a habit of doing one of two things. First, the surface where the thermostat (and ring gasket) sits builds up rust/debris causing the thermostat to not seat properly, and thus, not seal properly. This makes it run as though there is no thermostat. The other problem comes from the top of the housing rusting and eventually flaking off. The flakes build up in the cooling system and will eventually stop up the works. Mine accumulated in the heater core and caused a false low temp condition because one(?) of the temp sensors was in the heater lines and couldn't get a correct reading due to lack of coolant flow.

 

[Decker]

Earl43P I guess I don't KNOW its going closed loop, only guessing because of the raw fuel smell coming from the exhaust. Its smelling like my 96 bronco did when it was running too rich due to faulty o2 sensors. I will be pulling the tstat out again this weekend I guess.

 

[chillymorn]

well what did you get figured out? I'm having the same problem.