Radiator Cap?
Thread Starter
|
Senior User
Joined: Dec 2013
Posts: 136
Likes: 0
Radiator Cap?
Okay so here's a question that arose to me out of the blue since I'm having trouble with leaking radiators including my brand new one. I feel kinda dumb asking this but it sorta seems logical to me... I've seen a lot about how a bad radiator cap can cause problems with lack of pressure and lead to overheating but I haven't seen much of anything the other way. The only thing I realized I didn't do when I replaced my radiator was change the cap. If my cap is bad or corroded and stuck solid in the closed position, could this cause it to not allow pressure to bleed off and that's why the seams are blowing out of my radiators? If I build up heat and pressure gets too high for the radiator, but can't bleed off because the cap is bad it might be leading to the pressure taking the easiest route, being out the seams of my rad. tanks right?
1983 F-250 XLT reg cab custom steel flatbed, custom steel front bumper w/ warn winch, 33" BFG all terrains, 7.3L IDI, tuned injection pump, 2.5" duals to single 4" exhaust, gauge pods, C-6 auto with shift kit. p.s... yes it was converted from a 6.9L.
1983 F-250 XLT reg cab custom steel flatbed, custom steel front bumper w/ warn winch, 33" BFG all terrains, 7.3L IDI, tuned injection pump, 2.5" duals to single 4" exhaust, gauge pods, C-6 auto with shift kit. p.s... yes it was converted from a 6.9L.
Thread Starter
|
Senior User
Joined: Dec 2013
Posts: 136
Likes: 0
Well I got in touch with the company about the warranty on my brand new failure of a radiator and I've got a new replacement on the way. I ordered a new cap to go with it too. I was just looking for some opinions or experiences with whether it was possible or if my mind was deceiving me.
Tuned
Joined: Jul 2012
Posts: 426
Likes: 0
From: Topeka,Ks.
Usually what happens is they won't hold pressure. It is possible that the vent is plugged up. But there only suppose to vent in case of a overheat. Is your vehicle overheating? Or are your radiators just failing?
Thread Starter
|
Senior User
Joined: Dec 2013
Posts: 136
Likes: 0
No I'm not overheating at all. I have an electronic water temp gauge and the max temp I hit is about 205... And that's a new sender right in the block at the hottest point. Is that high? I've lost 2 radiators now and both have blown out in the same spot at the top seam in the front of the tank the whole way along the top of the radiator. The cap has a 13 psi rating right so doesn't that mean if the internal Pressure reaches that it will vent off to the overflow tank and out? I'm thinking toward this because I had my old radiator patched once, I drained the top tank, dried it all, sanded and cleaned the crap out of it, had it all sealed up and ran it for a day and it blew out again. I feel like I'm building too much pressure and it's blowing through the seams since that's the easiest and most weak point.
1983 F-250 XLT reg cab custom steel flatbed, custom steel front bumper w/ warn winch, 33" BFG all terrains, 7.3L IDI, tuned injection pump, 2.5" duals to single 4" exhaust, gauge pods, C-6 auto with shift kit. p.s... yes it was converted from a 6.9L.
1983 F-250 XLT reg cab custom steel flatbed, custom steel front bumper w/ warn winch, 33" BFG all terrains, 7.3L IDI, tuned injection pump, 2.5" duals to single 4" exhaust, gauge pods, C-6 auto with shift kit. p.s... yes it was converted from a 6.9L.
Tuned
Joined: Jul 2012
Posts: 426
Likes: 0
From: Topeka,Ks.
205 doesn't seem to high. These radiators you're getting are they, brass, aluminum, or aluminum with plastic tanks? I would think it would take quite a bit of pressure to blow a tank. Have you check your hoses when it's hot? Check them with it running. They should be under pressure but it will be pretty easy to feel if they have so much pressure as to damage something. If that's the case you may have a head gasket leak.
Thread Starter
|
Senior User
Joined: Dec 2013
Posts: 136
Likes: 0
The radiator that I bought is a copper core with brass tanks. I can't say I've paid a lot of note to the hoses now that you mention it, but wouldn't I be experiencing other issues if it was a head gasket? I've got full power and all the torque it ever had and the only leakage from anywhere is the seam that blew out.
Trending Topics
Junior User
Joined: Jan 2014
Posts: 73
Likes: 0
From: norway
What kind of coolant have you been using and the water that you have mixed with coolant is it clean ?? There should not be more than 12-16 psi depending on what kind of brand the radiator cap is i think. . Maby you should get a cheap coolant pressure tester and see what kind of pressure you have on the system, at least you would know if you have a broken gasket or blockage of some sort
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
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
Junior User
Joined: Jan 2014
Posts: 73
Likes: 0
From: norway
Oki, just wondered, but to your other question when the coolant reaches the set temperature of the thermostat and the pressure of the radiator cap it should just let the exess coolant/steam through to the coolant reservoar, atleast that's what it does on my 93 7.3idi and i only have that OE "stupid" temperature gauge in the dashboard
Thread Starter
|
Senior User
Joined: Dec 2013
Posts: 136
Likes: 0
That's my only other real thing to go on is that the coolant level in my overflow reservoir hasn't changed at all. It doesn't go up or down at all like it should through hot and cold cycles. Hasn't changed a 1/4" since I replaced the radiator even after all the leakage.
Postmaster
Joined: Dec 2011
Posts: 3,860
Likes: 7
Rad cap is just a few dollars from Napa; just drop one in. No risk, really.
As far as your rad goes, You can either keep replacing it, or find one that's good aside from your leak and see about fixing it.
Shouldn't be a problem to just clean and solder it all up with some plumbing solder, being brass and all.
As far as I can tell, there aren't a lot of quality replacement radiators out there; so finding one with a known failure and toughening up that point seems like a decent option.
As far as your rad goes, You can either keep replacing it, or find one that's good aside from your leak and see about fixing it.
Shouldn't be a problem to just clean and solder it all up with some plumbing solder, being brass and all.
As far as I can tell, there aren't a lot of quality replacement radiators out there; so finding one with a known failure and toughening up that point seems like a decent option.
Thread
Thread Starter
Forum
Replies
Last Post
MagKarl
1994.5 - 1997 7.3L Power Stroke Diesel
1
Feb 13, 2008 11:05 AM
wannabronco
1973 - 1979 F-100 & Larger F-Series Trucks
13
Dec 11, 2004 03:47 PM