Stumper: cooling system problem
Thread Starter
|
Post Fiend
Joined: Mar 2002
Posts: 19,402
Likes: 38
From: Bonita Springs FL
Stumper: cooling system problem
This is a strange problem... the whole story:
When I bought my truck, the thermostat was stuck open. I bought a temp gauge for it, and the temp never got above 130 or 140. I put a new thermostat in it (the old one was really cruddy and broke in half when I tried to play with it) and it's been working fine ever since. 195 right on the nose the whole time.
Until last night. All of the sudden, the temp started to drop down. It wouldn't stay at 195 anymore. It never got much past 180. On the way to work this morning, it didn't go over 140. So I stopped at Napa and got a thermostat and gasket. I put it in tonight. The old one looked fine when I took it out. I took it for a drive and it still won't get past 140.
I'm pretty sure it's not the gauge, because I can get it to heat up by driving around in granny low. The loss of air flow is enough to get the temp up. As soon as I get it up to 30 or so, the temp drops back down.
Every other cooling system problem I know of causes a motor to overheat, not underheat.
Any ideas?
The truck is an '89 F-150 with a 300 and a T-18.
When I bought my truck, the thermostat was stuck open. I bought a temp gauge for it, and the temp never got above 130 or 140. I put a new thermostat in it (the old one was really cruddy and broke in half when I tried to play with it) and it's been working fine ever since. 195 right on the nose the whole time.
Until last night. All of the sudden, the temp started to drop down. It wouldn't stay at 195 anymore. It never got much past 180. On the way to work this morning, it didn't go over 140. So I stopped at Napa and got a thermostat and gasket. I put it in tonight. The old one looked fine when I took it out. I took it for a drive and it still won't get past 140.
I'm pretty sure it's not the gauge, because I can get it to heat up by driving around in granny low. The loss of air flow is enough to get the temp up. As soon as I get it up to 30 or so, the temp drops back down.
Every other cooling system problem I know of causes a motor to overheat, not underheat.
Any ideas?
The truck is an '89 F-150 with a 300 and a T-18.
Thread Starter
|
Post Fiend
Joined: Mar 2002
Posts: 19,402
Likes: 38
From: Bonita Springs FL
Well, I took it to a mechanic today. He has a laser thermometer, and he tested all the hoses and the thermostat housing. Everything checked out temp-wise, so it looks like the gauge is wrong. Cheap autozone craps bites me again.
Postmaster
Joined: Dec 2003
Posts: 2,659
Likes: 2
From: S/C Texas
Coulda just dropped a kitchen thermometer in the radiator.
Ofcourse you might drop it in the engine compartment, to never be seen again. No that it mattered, I was still trouble for using my wifes thermometer.
Yea, I too refuse to learn. I have gotten better.....no more electrical from AZ.
Ofcourse you might drop it in the engine compartment, to never be seen again. No that it mattered, I was still trouble for using my wifes thermometer.
Yea, I too refuse to learn. I have gotten better.....no more electrical from AZ.
Last edited by peppy; Aug 20, 2004 at 05:01 PM.
Thread Starter
|
Post Fiend
Joined: Mar 2002
Posts: 19,402
Likes: 38
From: Bonita Springs FL
I know - but I didn't have a thermometer to use. I'd really like to get a laser thermometer, but I think they're a little pricey. I don't need to know how hot various things in the engine compartment are *that* bad.
Senior User
Joined: Mar 2003
Posts: 259
Likes: 2
From: SOUTHERN NEW JERSEY
Trending Topics
Freshman User
Joined: May 2004
Posts: 26
Likes: 0
I use a candy thermometer. It reads to about 500 degrees fahrenheit. Just stick it in the filler hole on your radiator. You will not get into trouble with it because not many wives make homemade candy any more.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Junior User
Joined: Nov 2003
Posts: 54
Likes: 0
Originally Posted by peppy
Coulda just dropped a kitchen thermometer in the radiator.
Originally Posted by altonjh1
Just stick it in the filler hole on your radiator.
Thread Starter
|
Post Fiend
Joined: Mar 2002
Posts: 19,402
Likes: 38
From: Bonita Springs FL
You can buy a cap that has a release valve that will dump the pressure into the overflow reservoir, allowing you to open the radiator.
Candy thermometer - good idea. Sounds like something I need to buy.
Candy thermometer - good idea. Sounds like something I need to buy.
Thread
Thread Starter
Forum
Replies
Last Post