Stupid Radiator Q
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New User
Joined: Oct 2002
Posts: 24
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From: Fort Collins USA
Stupid Radiator Q
I think I already know the answer, but I want to ask anyways.
My truck has never overheated, and the temp gauge rarely climbs out of the C, but last night, I checked under the hood and saw the the radiator reservior is empty. I think I can see a line on it for the min and max, but I don't see anything in there?!?!
Oh yeah, F250, 1989. Should I just flush the system and fill it again? I figure it might need it anyways since I don't know the history of the truck. Or should I just leave it since it ain't overheating?!?! Or should I just fill the reservior?
My truck has never overheated, and the temp gauge rarely climbs out of the C, but last night, I checked under the hood and saw the the radiator reservior is empty. I think I can see a line on it for the min and max, but I don't see anything in there?!?!
Oh yeah, F250, 1989. Should I just flush the system and fill it again? I figure it might need it anyways since I don't know the history of the truck. Or should I just leave it since it ain't overheating?!?! Or should I just fill the reservior?
Posting Guru
Joined: Sep 2002
Posts: 2,420
Likes: 3
From: Langhorne, PA
Stupid Radiator Q
Ford must have done something wrong when they designed the cooling system for the 80's and 90's trucks.I have the same problem,and posted a couple of questions like yours.But my point is that, a lot of guys are complaining about mysterious coolant loss in these threads.Some answers say it is normal for a slow loss of fluid over time. I would just keep an eye on how much coolant you lose or replace and write it down in a log.
Senior User
Joined: Jan 2002
Posts: 185
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From: Central Florida, USA
Stupid Radiator Q
I think the plastic resevoir on this era truck is just something attached to the windshield washer fluid container. Mine, on my '92 F-150, is ofter dry but the cooling system is fine and the radiator is full. When I used to let the quick-lube folks change my oil they would bring me a sample of water from the resevoir (when it had any in it) and try to sell me a flush. Ha! They never actually looked at the cooling system which was clean and recently flushed. Have a look in the radiator itself before thinking you have a problem. If you do not see signs of leaking around the engine compartment, your cooling system is topped off and your temperature is not out of the range you normally see I'll bet everything is fine.
Junior User
Joined: Dec 2001
Posts: 50
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Stupid Radiator Q
The radiator expansion tank on my '92 F150 I-6 is also often dry. I have to top it up every two months or so.
The interesting thing about it is that it is not a sealed system... IOW, on other cars, the expansion tank is pressurized with a big pressure cap on top. On the F150, it is a simple, unpressurized cap that must leak out moisture. The radiator is fine... topped up to the top, and even when pulling a trailer, the temp gauge never goes above 1/4.
As other posters have said, just top it up and check it every so often.
The interesting thing about it is that it is not a sealed system... IOW, on other cars, the expansion tank is pressurized with a big pressure cap on top. On the F150, it is a simple, unpressurized cap that must leak out moisture. The radiator is fine... topped up to the top, and even when pulling a trailer, the temp gauge never goes above 1/4.
As other posters have said, just top it up and check it every so often.
Postmaster
Joined: Mar 2001
Posts: 4,968
Likes: 3
From: So Cal
Stupid Radiator Q
Yeah, just top it off and check on it every few days for awhile. If it is just normal fluid loss, you will need to top it up a couple times until all the bubbles are out of the system. If you have a leak, it will need topping up frequently. I would estimate normal is to lose maybe 1 quart every couple oil changes or so. Losing a quart every few hundred miles would indicate a problem.
Up until maybe the mid 90s most cooling systems had an open overflow/fluid reservoir and a pressure sealed radiator. Now many cars had sealed systems with the overflow tank pressure sealed and sometimes no radiator cap on the radiator. I have noted and so have some websites, that the newer plastica pressure caps seem to be more prone to plugging up and leaking than the older raditor caps. Might be worthwhile to check. Even the old metal caps would wear out and cause "unexplained" fluid loss.
My 94 F250 does occasionally need a top up but usually not much and only infrequently.
Good Luck,
Jim Henderson
Up until maybe the mid 90s most cooling systems had an open overflow/fluid reservoir and a pressure sealed radiator. Now many cars had sealed systems with the overflow tank pressure sealed and sometimes no radiator cap on the radiator. I have noted and so have some websites, that the newer plastica pressure caps seem to be more prone to plugging up and leaking than the older raditor caps. Might be worthwhile to check. Even the old metal caps would wear out and cause "unexplained" fluid loss.
My 94 F250 does occasionally need a top up but usually not much and only infrequently.
Good Luck,
Jim Henderson
5th Wheeling
Joined: Mar 2002
Posts: 48
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From: O'Fallon United States
Stupid Radiator Q
I have a 95 F-150 with a 5.8. I get the same "unexplained loss of fluid from the resevoir", although my seems more prone in the winter time. One thing I have noted is that when the temperatures get colder, the plactic endcaps on my radiator will seep coolant where they are crimped onto the core. I talked to a guy at one of the local Ford dealerships. He said this was normal as the radiator gets older.
Senior User
Joined: Jan 2001
Posts: 416
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Stupid Radiator Q
There could als be a slight los through the seal on the water pump shaft, these leaks go un noticed until the seal really starts to fain and a puddle appears under the truck when parked.
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Elder User
Joined: Aug 2000
Posts: 763
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From: home
Stupid Radiator Q
Had the same problem on my 92 v/8 F 150. Replaced all the hoses & still no fix. Put a peace of paper towel in the water pump weep holes and ran the truck on a trip. Checked the paper towels in the weep holes the next morning & they were discolored. A leaking water pump! Replaced it and one year of driving and no fluid added. I also have a 4.0 Aerostar & 89 Bronco II that I rarely have to add coolant to the overflow tank. I even have a 74 Ford Maverick with 154 K miles with a home made overflow tank & original radiator ( never pulled) that I rarely have to add water. I would check all the hose connections and look underneath them with a light for water spots, discoloration etc.
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New User
Joined: Oct 2002
Posts: 12
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From: Red Deer
Stupid Radiator Q
You know I too have an 89 f-150 with a coolant resevoir that is always empty. I dot know why but if I fill it up it just drais away somewhere. I think ford must have had extra in stock and needed somewhere to put them.
