New radiator now an over pressurized system

[mooseracing]

I'm digging for ideas here.

I've had a leak at the top of my radiator for ever, today it decides to finish itself off. I'm sure I got it a little too warm. So I pick up a replacement from NAPA and R&R. I've bled the system by cracking the hoses and getting air but I've repeated the cycle way too many times in my mind. The hoses are all getting rock hard and I think the tstat is opening once and awhile since I get heat. If I start it up while it is pressurized it vents out the radiator cap and overflow tank. I've let it run for alittle bit again and hoping as it cools off it can work some out. I also have it parked on an incline.

I see no coolant in the oil or vice versa. Exhaust is clear. But I just and not getting why it is so pressurized.

'94 non turbo.

 

[The Warden]

Have you replaced the thermostat, and did you buy and test a new pressure cap when you replaced the radiator?

Also, just a thought...have you tried running it with the pressure cap removed, to see whether you're getting air bubbles or if the coolant pushes itself out of the radiator?

 

[whiteboyslo]

OE radiator cap is 13psi, which should get the hoses pretty firm once heated up.

Not sure I'm following how you're bleeding the system, but anytime I've had to drain the radiator, I always use the following sequence to re-fill/bleed the system:

1. Fill radiator, at least until coolant covers the top of the core assembly (as viewed inside the cap opening)
2. Fire it up with the cap off and let it come up to temp. This can take a while
3. Once the truck gets hot enough that the thermostat opens and the coolant starts to drain from the radiator, keep filling. DON'T top it off because the system will be burping itself and it'll just make a mess
4. Once all the coolant bubbles have died down, top it off, throw on the cap, and shut it down
5. Let it cool all the way down, then pop off the cap. The system shouldn't be under pressure at this point, but I've found this to not always be the case. To minimize the mess made by opening a pressurized system, I use the rad caps that have the relief valve in them.
6. Top off the rad, then top off the overflow
7. Throw the cap back on

Mike

 

[mooseracing]

1. Fill radiator, at least until coolant covers the top of the core assembly (as viewed inside the cap opening)
2. Fire it up with the cap off and let it come up to temp. This can take a while
3. Once the truck gets hot enough that the thermostat opens and the coolant starts to drain from the radiator, keep filling. DON'T top it off because the system will be burping itself and it'll just make a mess


Mike

Pretty much how I do it, then this one continued to be hard so I cracked some heater lines as AllData says crack the one coming off the pump until it has coolant coming out. I've tried others for kicks but nothing is helping.

I've swapped caps with other Fords I have and it isn't helping. The system is pressurizing instantly. If I try to fill the rad above the cores it spits out that coolant. The first time we filled it up we were getting heat, now I am not getting any even though the engine temp shows high when I take it for a drive, the air is cold. Where is the best place that I have a better chance at a stocked T-stat? IH?

I don't drive this truck in the snow, so if I can't get parts within the next day or two to get me another week or so of driving, I am probably going to park it till spring.

 

[PackRat239]

Sounds like a head gasket to me.

 

[whiteboyslo]

Pretty much how I do it, then this one continued to be hard so I cracked some heater lines as AllData says crack the one coming off the pump until it has coolant coming out. I've tried others for kicks but nothing is helping.

I've swapped caps with other Fords I have and it isn't helping. The system is pressurizing instantly. If I try to fill the rad above the cores it spits out that coolant. The first time we filled it up we were getting heat, now I am not getting any even though the engine temp shows high when I take it for a drive, the air is cold. Where is the best place that I have a better chance at a stocked T-stat? IH?

I don't drive this truck in the snow, so if I can't get parts within the next day or two to get me another week or so of driving, I am probably going to park it till spring.

So, if you start the truck with the engine COMPLETELY cold (cap on), you're saying the top hose instantly gets hard?

Yeah, sadly that sounds like head gasket or MAYBE a thermostat stuck open.

Mike

 

[icanfixall]

You made a comment that the oem radiater had a leak and you may have gotten it too hot. So exactlyy what are you telling us. You ran the engine a long time with no or very little coolant in the engine??/ If so then you may have ruined a head gasket. Now this pressurizing instantly. Not really possible but your thinking it is. so do this. Loosen the cap but don't remove it. This will allow the coolant to pass into the recovery tank but not spill out of the cap. See how that works. I'm guessing your running the factory dash gauge too. You may want to change the thermostat. Use only the factory thermostat that opens at 192 degrees. Many others will fit our engines but they can't pass enough coolant to keep things cool. You posted you had a leak so maybe your stat is the wrong on causing a high pressure build up.

 

[mooseracing]

So after this headache I was under the gun to get a backup car going. Which needed a water pump, then needed a power steering pump, then had fun at the secretary of state. Now that I have a breather and think I have something to drive, anything recommended while the head is off? I need to pick up a pressure tester to figure out which side has the issue. But I was thinking at 210,000 I would throw in new valve seals, valve job, oil cooler re-ring (if drivers side head), new heater hoses it has needed, and new tstat.

Anything else worth messing with on a stock NA. I'm going for longevity here.