Temp rising at idle

[Natev22]

Hello,

I would love to have some input on a problem I'm having. The 2f is getting pretty hot when I'm sitting still. It gets to just below the Red Mark on the gauge.

When I'm driving, the temp comes back down. My first thought was it's an airflow issue. I went ahead and ordered a new fan clutch and fan. My current fan clutch has the same resistance as the new clutch, so I think it's something else.

Then I noticed a small drop of coolant on the driveway. It seems to be coming from below the water pump. Dripping from the very front of the oil pan. But it doesn't seem to be coming from the water pump. There is also what seems to be coolant dripping from the drivers side bump stop. It must be splashing over there. I have topped it up but it's still getting hot. Could a small leak cause the truck to get hot? Just a lack of pressure?

Any suggestions? Thanks!

 

[Spike Strip]

Could be coming from the weep hole in the Water Pump ... Sometimes it trickles out and snakes its way along the block. Often hard to spot without a telescoping mirror. Have you put the new FC on yet?

 

[Natev22]

Nope I just put the old FC back on. I couldn't tell the difference between the two, so I used the old one. The fan seems to spin fine

 

[Spike Strip]

The FC 'locks' the fan at set temp so it pulls air thru the radiator, if it's spinning freely at idle, it's not pulling much air and temp increases. It's that characteristic 'roar' you might hear at idle when the FC is engaged. You can't test a FC just by feeling how the fan spins... If your FC is original, it prolly needs replacement. Same for WP.

Did you get the Aisin FC?

 

[Natev22]

No the old one had the same resistance as the new one and the fan spins great when the engine is running. It's really stiff when I spin the FC by hand

 

[OSS]

when the coolant is drained & refilled, the temperature gauge can show Too Hot at idle for up to two weeks until all the bubbles get worked out

 

[Natev22]

It cools down when I'm driving down the road but if I stop for now than a could minutes, it heats back up

 

[Seth S]

When was the last time you changed the thermostat?

 

[MrMcgoo]

I’m having the same issue and it has been awhile since fluid was changed. No leaks that I can find. Though it has been real hot here when driving but still running hotter than it should.

 

[BlackCat]

Can’t believe it hasn’t been said yet, but DO NOT trust your factory gauge. Sure, it’s probably vaguely accurate, but I’ve seen countless people chasing their “overheating” issues when, in fact, the truck wasn’t running that hot in the first place.

Same thing goes for me; I recently got my A/C fixed in my 83. Drove it home from work in 115 temps, and whaddya know, the gauge crept up to over half way with the A/C on. I panic a bit, then realize I tell people not to trust the gauge all the time. Using my IR gun, it’s running at 205. Point being, make sure it’s overheating before thinking and spending money on it overheating.

 

[Natev22]

I just had ac work done as well. I'll look into that. Where do you point the IR gun? Just measure the temp of the radiator?

 

[Seth S]

Point it at the radiator. The tstat housing. The head. The hoses. The water pump. Basically take a whole bunch of readings to get a feel for the actual temp

 

[Elbert]

when my truck was stock, you could place your hand in front of the condensor/radiator while engine running in hot ambient temps but engine at normal temp and you could feel air coming across the radiator, a/c on or a/c off. Truck sitting still. An old fan clutch needs to go.

ensure you know what the temp really is (comment above about the OEM gauge is true), also assume the coolant system is full and no air pockets.

if coolant is leaking from the weep hole on the water pump, you need a new water pump.

also assumption is that your other cooling components are in good shape, fan, fan shroud, radiator, thermostat and that you have nothing blocking the radiator. and that your belts are tight.

 

[Natev22]

I appreciate everyone's input. I discovered that the fluid on the bumpstop is actually power steering atf. It's leaking right at the steering gear shaft.

1 step forward, 6 steps back! Haha

Now I'm shopping for a rebuild service for the steering box. I don't have the time, energy, tools, know-how, or space to do it myself.

I guess I just hijacked my own thread. Is West Texas off road still rebuilding for a reasonable rate. It looks like Lares will do it for around $200.

 

[ROFF]

Is your AC operating when it does this? If its working when it previously didn't then the condenser will heat up the air before it passes over the radiator. Mine will go right to the red if I have the AC on at idle. If I pull the choke and bump the RPMs up to 1500 then the fan pulls enough air to keep the temp gauge mid range. What is your idle set at with AC off and AC on?

 

[Spike Strip]

Yes. WTOR is the place to send it.

 

[MrMcgoo]

I was driving today and the gauge would sit Hal way and then creep up to just below the red. When I returned home I shut it off and opened the hood. A few minutes later I used the temp gun and the reading on the rad was under 200 but the upper hose was reading about 213 and just for the heck of it put in on the block which was about 220. Today the outside temp was 108.

 

[Michael Hanson]

Hi, Put a piece of notebook paper in front of the radiator at idle, does it stay or fall down ? Mike

 

[FJ60Seth]

You could have air trapped in the coolant passages. Search for “burping”. If that doesn’t solve your overheating problem, take another look at the fan clutch. When your engine is hot & idling, take a rolled up piece of newspaper, like you’d smack a fly with, and feed it into the fan blades. The fan should chew up the newspaper before it stops & make you think “I wouldn’t want to put my hand in there”. If it doesn’t, swap your fan clutch with the new one. Where did you buy the new one from? How is branded? Where is it made?

 

[SteveH]

Point it at the radiator. The tstat housing. The head. The hoses. The water pump. Basically take a whole bunch of readings to get a feel for the actual temp

Be sure to turn off the engine first. My IR temp gun read 15 degrees high with the 'wind' due to the fan spinning. IR temp guns are sensitive to moving air!