73 f100 302 3 on the tree 2wd.

since i've had it it had a leak in front of the radiator....i took it out and soldered it and put it back in....i noticed that the truck was running too warm...between M and P on the stock gauge....and when i turned it off the water sounded like it was boiling. i then had the radiator cap basically give out and blow a butt load of water everywhere....i changed the cap and had it running again....this time when i turned it off another joint right above the solder i did blew out...completely blew out this time since it looked like an old solder....well i fixed that re soldered both of the holes and had no problems....but this time i took out the T-stat too....it seemed to help it run cooler...but still when i turned it off i could still hear the bubbling....today i was out just running around the neighborhood to see how she ran and when i got back home i heard it bubbling...as i walked away it popped the upper radiator hose...blew it in half where the clamp was....my question is why am i having these troubles? what's causing the bubble and the over heating....with no T-stat and the water pump working i'm not getting why it's messed up.....any input...

if it matters any the heater core is bypassed..since the core leaked from previous owner...thanks guys...

 

I love it when you fix something, and it causes the next weakest link to break. I would get a thermostat on that thing in the near future. It's not good to run without them. Did the new cap have a PSI rating of about 13? Fan working properly?

 

I would be looking for a crack block or head or a bad head gasket.

 

the cap has a rating of 16 lbs i'm pretty sure...and i took it off of a working radiator and stuff....

i know all about the head gasket thoughts and i did alot of research on it....i have had bad heads/gaskets before and usually resulting in water in the oil or in the cylinder...neither of those according to the plugs...they look okay..used but okay....and there is no water in the oil...and i'm getting good clean air out the exhaust no steam...the next was to check for bubbles in the radiator...i tried that too..had the girlfriend put it in 1st and kinda let out the clutch and put a load on it...but it didn't change anything...no bubbles coming out of the radiator...also i noticed that the lower tank was cooler than the top like it should be....it's got me stumped...i'm going to redo the head gaskets and get all new cooling stuff but it's not in the budget just yet...still trying to get the gaskets in line for the heads and things of that nature then i'll do a new water pump and t-stat and i'm supposed to be getting a new used but good radiator...


any other ideas?

 

You need to get a rad psi checker on it and pump it up to see if it leaks off.

 

i know the radiator isn't the best shape but it's not leaking anymore and i would noticed it with it having the pressure to blow the weak spot out of my radiator hose...it would have pushed water or steam out somewhere...even where i soldered it it is sealed good...it seems to me that it's building pressure somewhere and it should be able to release but what i'm not getting is why i hear bubbling when i turn the engine off.

 

Since you have no thermostat installed, when the engine is running can you see good water flow with the radiator cap off?

 

yes the water is flowing well...atleast until it blew the radiator hose.

 

no t-stat can cause problems just as bad as a bad t-stat. you to do a couple of tests. first off, as mentioned already, do a pressure check on the cooling system. if the system cannot hold pressure, it will overheat. if the radiator, hoses, heater core , and everything is absolutely 100% sealed and it wont hold pressure, chances are you have either a bad head gasket or a cracked head/ block.

the next test to check for a failing head gasket is to use a combustion leak checker. autozone and napa both sell these. they use a blue fluid to check for combustion gasses in the cooling system and when present, the fluid turns yellow.

try a proper t-stat and cap first.

 

You can have a cracked cylinder wall. It would not contaminate the cooling system or oil. But would build pressure in the cooling system causing things to blow out. Head Gasket bad in the right place can do this also. Just because nothing is contaminated don't mean ya may not have a break.

 

so whenever i get the money for the gasket set is there anyway to check the cylinder walls when i get the head off of should i just try to find a new engine? none of this was going on until after i put the engine back in after a clutch job...before the guys burned the clutch out it ran fine and they where driving it daily. i even drove it once befor that and it was fine....i didn't find the leaking radiator until i started it up to move it into the garage and when i looked at the gauge it was running warm...when i tuned it off i had a spray stream from the front of the radiator.

 

Like was said before. Rent or borrow the pump to pressurize the cooling system and do a leak down test to see if there is a crack or something before ya tear it down. Trouble shoot the problem than know how bad it is and what it will take to fix.

 

My 79 F150 boils coolant over into the overflow when I first turn it off b/c of the extra heat build up when engine isn't running.
Runs 190 degrees all day long, normal driving or hot doggin the living crap out of it. Turn it off and it goes up to about 215 for 10 minutes or so then starts going back down. I'm not running the correct cap though, I think mine is only 7 psi.

Surprised nobody has said anything about a leaking intake gasket since 302s have water circulating through the front of the intake.

 

ill say it again. only in bold this time.

 

If your talking to me I know what you already said. I was just bringing up that it could be the intake gasket leaking.