Inline 6 questions
Thread Starter
|
Junior User
Joined: Mar 2004
Posts: 54
Likes: 0
From: Farmington, Iowa
Inline 6 questions
I have heard that a 4.9 liter Inline 6 in a cool running engine. I cant seem to get any heat out of my engine. The guage is always on the "c". So I was wondering what I can do to make it run a little warmer? or if there is anything TO DO? I have a 1989 Ford F-150 4.9 2WD XLT Lariet All help is appriciated! 
Senior User
Joined: Mar 2004
Posts: 425
Likes: 0
From: Roanoke
Check to be sure it has a thermostat in it and check to be sure that it is the correct temperature rating. also if you have a clutch fan make sure that the fan turns freely when the engine is off and cool. You also might change the sending unit, it may not be reading correctly. Hope this helps.
Posting Guru
Joined: Sep 2002
Posts: 2,420
Likes: 3
From: Langhorne, PA
If the heater barely works and warms up just enuf to keep you alive on a 12 degree F morning then it is working OK 
My truck pulled that stunt when it was around 40,000 miles. I went all winter freezing my butt off. Changed the thermostat flushed the cooling system and refilled with new fluid and all was OK.
My truck pulled that stunt when it was around 40,000 miles. I went all winter freezing my butt off. Changed the thermostat flushed the cooling system and refilled with new fluid and all was OK.
Post Fiend
Joined: Mar 2002
Posts: 19,402
Likes: 38
From: Bonita Springs FL
Actually, the 300 has a higher tendency to overheat that the V8's do. The coolant has to flow around 6 cylinders in a 300, and only around 4 in a V8. So they don't keep cool as easily.
If the gauge is always on C, the sender is probably bad. Even with no thermostat, it should move a little. Make sure you replace the thermostat with a 195 degree one.
Does the heater work?
If the gauge is always on C, the sender is probably bad. Even with no thermostat, it should move a little. Make sure you replace the thermostat with a 195 degree one.
Does the heater work?
Thread Starter
|
Junior User
Joined: Mar 2004
Posts: 54
Likes: 0
From: Farmington, Iowa
yes the heater does work but it is like 924X2150 was saying in his post it barley keeps me warm. I have checked the anti-freeze level and it is always full. I will check to see if the thermostat is in there and/or put a 195 degree one in. I was also thinking about flushing the cooling system or do you think that is nessesary. Where is the sending unit located at?
Thanks for all the help I have already got and please send more!
Thanks for all the help I have already got and please send more!
Post Fiend
Joined: Mar 2002
Posts: 19,402
Likes: 38
From: Bonita Springs FL
The cooling system should be flushed every 30,000 miles. If you just got it, chances are the previous owner never had it done, and you should think about doing it.
The sending unit for the gauge is on the passenger side on the rear of the block, just under the exhaust manifold. Easy to get to, right? I usually drop the starter, but I've heard of other people getting to it from the side.
The sending unit for the gauge is on the passenger side on the rear of the block, just under the exhaust manifold. Easy to get to, right? I usually drop the starter, but I've heard of other people getting to it from the side.
Mountain Pass
Joined: Jul 2004
Posts: 245
Likes: 41
9 times out of 10 it's the thermo. this was the case on my 300 as well. watch out for the water outlet.. they like to crack when you put them back on.
Trending Topics
Cargo Master
Joined: Sep 2004
Posts: 2,688
Likes: 6
If there's not enought heat it's probably the tstat. Even if there's one in there that doesn't mean it's working. They'll fail and stay open and you never get enough heat. Toss that and put in a new one. They're only $5. My truck keeps me toasty warm no matter what the temp is outside. I flushed mine this past summer. The overflow tank was so rust coated that you couldn't see the green of the coolant. It was dark. There was an inch of rust powder on the bottom. I took out the overflow tank and blasted it clean with the hose. Then I flushed the system. It took forever to get it to where rust wouldn't come out. Then guess what. Water pump starts leaking. I guess all that rust buildup was keeping the water pump sealed. Replaced that next and now all is well. But I ain't kidding. My coolant was the color of rust. It wasn't green. This was at 140K mi. I bet the coolant had never been changed. It was probably original.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
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
Ford Super Duty: 5 Things Owners LOVE, 5 Things They LOATHE!
Joe Kucinski
Every 2026 Ford Truck Engine RANKED from WORST to FIRST!
Michael S. Palmer
The Best F-150 Deal of Every Trim Level (XL through Raptor)
Joe Kucinski
Posting Guru
Joined: Sep 2002
Posts: 2,420
Likes: 3
From: Langhorne, PA
Speaking of cracking things....I had a leak from the upper hose at the radiator inlet. Since it was a new hose I kept tightening the clamp thinking the assy. will settle and seal sooner or later. After a week of leaking I finally took the hose off the upper port of the radiator and found the plastic inlet had cracked close to the side tank assy. I am thinking I leaned on it one too many times or overtorqued that clamp.
Moral of the story;be careful the sidetanks are plastic!
I wouldn't touch the coolant sensor, my truck was on "C" the first winter after I bought it, (November 95) I changed the thermostat later and it was OK after that. If you are cold in the cab, and the guage reads zero, then all clues point to an overcooled engine due to a stuck-opem tstat.
Moral of the story;be careful the sidetanks are plastic!
I wouldn't touch the coolant sensor, my truck was on "C" the first winter after I bought it, (November 95) I changed the thermostat later and it was OK after that. If you are cold in the cab, and the guage reads zero, then all clues point to an overcooled engine due to a stuck-opem tstat.
Elder User
Joined: Dec 2004
Posts: 742
Likes: 2
From: Eastern Iowa
With mine,when it gets really cold the truck will not warm up enough to pump out heat. I put a piece of cardboard between the radiator and the AC condenser and the problem was immediately solved. I was reminded of this midwinter fix yesterday when it got really warm for the first time, and the temp rose 3/4 of the way across. I pulled over and took out the cardboard........all is well!
