Cooling System Staying Pressurized
Thread Starter
|
New User
Joined: Sep 2019
Posts: 12
Likes: 0
Cooling System Staying Pressurized
I have a '93 F250 with the 460 and 5 speed manual. After sitting for weeks my cooling system stays pressurized; when I remove the radiator cap coolant splashes out everywhere. I think this started happening right after I got my new radiator. I tried putting a new radiator cap on there (13 psi) and the problem is persisting. I was thinking maybe the radiator cap has too much spring pressure or has the wrong dimensions so that it doesn't let the coolant flow back into the overflow tank, but I'm not very sure. Not sure if this would be relevant, but I do have a very slow coolant leak coming from the oil cooler. Whenever I come to check the coolant, the radiator is completely full and the overflow tank is empty.
What could be causing the coolant to stay pressurized over long periods of time?
Also, is the 13 psi cap the correct one for my truck?
What could be causing the coolant to stay pressurized over long periods of time?
Also, is the 13 psi cap the correct one for my truck?
Elder User
Joined: Dec 2016
Posts: 854
Likes: 39
From: Mid Missouri
13 pounds cap is correct.
I’ve never had a vehicle that maintained pressure after engine cooled down, much less weeks after shutting off.
I had an issue a while back on this truck where the coolant wasn’t overflowing back into the reservoir when cooling down. I replaced the overflow hose and haven’t had a problem since.
I’ve never had a vehicle that maintained pressure after engine cooled down, much less weeks after shutting off.
I had an issue a while back on this truck where the coolant wasn’t overflowing back into the reservoir when cooling down. I replaced the overflow hose and haven’t had a problem since.
Junior User
Joined: May 2009
Posts: 68
Likes: 0
From: Frederiksted, USVI
Those little hoses tend to flake off on the inside and clog themselves up, never enough pressure there to really clean them.. Also, the cap may be the correct PSI but if the neck section (springy part with rubber seal) is too long it won't open far enough to expose the hose port. My money is on the hose itself, though, as EllieMae suggests..
Trending Topics
Cargo Master
Joined: Jul 2009
Posts: 2,541
Likes: 54
From: Des Moines
I have a '93 F250 with the 460 and 5 speed manual. After sitting for weeks my cooling system stays pressurized; when I remove the radiator cap coolant splashes out everywhere. I think this started happening right after I got my new radiator. I tried putting a new radiator cap on there (13 psi) and the problem is persisting. I was thinking maybe the radiator cap has too much spring pressure or has the wrong dimensions so that it doesn't let the coolant flow back into the overflow tank, but I'm not very sure. Not sure if this would be relevant, but I do have a very slow coolant leak coming from the oil cooler. Whenever I come to check the coolant, the radiator is completely full and the overflow tank is empty.
What could be causing the coolant to stay pressurized over long periods of time?
Also, is the 13 psi cap the correct one for my truck?
What could be causing the coolant to stay pressurized over long periods of time?
Also, is the 13 psi cap the correct one for my truck?
I’m guessing there’s no overheating issues? Is there a clear difference in temp between the upper and lower radiator hoses when it’s up to temp?
1) I agree to check that the overflow hose is clear and allowing coolant flow; however, even if it is plugged, that wouldn’t prevent the cap from venting properly. The pressure has to go somewhere, so if the overflow hose is plugged and it doesn’t get blown off the fitting, it will find the path of least resistance, wherever that may be.
2) It’s possible the system is never exceeding 13 PSI to begin with. Try fixing the oil cooler leak and see if that causes normal venting and overflow.
3) Radiator caps are cheap and parts are known to be bad out of the box - a few dollars to get another new cap and see if that resolves it seems worth it.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Top 10 Ford Truck Tragedies
Joe Kucinski
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
Thread Starter
|
New User
Joined: Sep 2019
Posts: 12
Likes: 0
Ok, thanks for the suggestions. I'll replace the hose and cap and check the upper and lower hoses when hot. Maybe I should check the thermostat too. Also does anyone know where I can get a new oil cooler?
Thread
Thread Starter
Forum
Replies
Last Post
Noveske
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
1
Apr 1, 2010 08:34 PM
ASH
Cooling, Heating, Ventilation & A/C
5
Aug 6, 2003 07:41 AM