UnFreakinBelievable Overheating
6th Gear Member
Joined: May 2009
Posts: 5,232
From: PA
Are you sure you installed the head gaskets correctly with the word "Front" towards the front of the engine? It is a common mistake to install one of them backwards as alot of people want to have the printing on the gaskets the same, but doing it that way usually results in one gasket being installed backwards.
These gaskets are both installed correctly. Notice they both say "Front" on them, but the printing design is not the same between the two. Match the printing and one of them is backwards leading to rapid overheating:
These gaskets are both installed correctly. Notice they both say "Front" on them, but the printing design is not the same between the two. Match the printing and one of them is backwards leading to rapid overheating:
Thread Starter
2nd Gear Member
Joined: Aug 2009
Posts: 476
From: NH
Yep, I put the gaskets on correctly but I have new developments...
I parked on a hill, on ramps so the nose was up quite a bit. Got the same result. But know I know my pump is moving coolent, and my thermostat is working fine. It looks like the problem is in the radiator. I'm getting pressure on the top hose and very little on the lower.
I also have some words to eat so I'll man up.
The fan may not be kicking on when it should be. This may be to a steam pocket in the radiator not activating the probe area of the rad.
There I said it.
I shut it off hot and slowly let out the air pressure. The lower hose was chugging hard, making a nice banging noise and shaking with each slam. Once all the air pressure was out I removed the cap and the coolent level was at the top of the neck.
Then the weirdest thing happened.
I manualy turned on the fan and after 2 seconds the water level dropped in the radiator about 6 inches and gurgling could be heard.
I'm at a loss.
Tomorrow I will try just running it with the fan on 24x7 and see what she does.
Could it be possible that there was a large steam pocket trapped under the top level of coolent? Once the fins cooled down it collapsed and dropped the level?
I have NEVER ran into such a weird problem in my years.
I parked on a hill, on ramps so the nose was up quite a bit. Got the same result. But know I know my pump is moving coolent, and my thermostat is working fine. It looks like the problem is in the radiator. I'm getting pressure on the top hose and very little on the lower.
I also have some words to eat so I'll man up.
The fan may not be kicking on when it should be. This may be to a steam pocket in the radiator not activating the probe area of the rad.
There I said it.
I shut it off hot and slowly let out the air pressure. The lower hose was chugging hard, making a nice banging noise and shaking with each slam. Once all the air pressure was out I removed the cap and the coolent level was at the top of the neck.
Then the weirdest thing happened.
I manualy turned on the fan and after 2 seconds the water level dropped in the radiator about 6 inches and gurgling could be heard.
I'm at a loss.
Tomorrow I will try just running it with the fan on 24x7 and see what she does.
Could it be possible that there was a large steam pocket trapped under the top level of coolent? Once the fins cooled down it collapsed and dropped the level?
I have NEVER ran into such a weird problem in my years.
6th Gear Member
Joined: May 2009
Posts: 5,232
From: PA
How about relocating the temp probe to the lower end of the rad, say, near the suction hose?
Last edited by 2+2GT; May 4, 2010 at 09:29 PM.
6th Gear Member
Joined: Jan 2007
Posts: 5,469
From: AR
The first thing I want to say to EVERYONE is to NEVER turn off an overheating engine unless you have no choice or KNOW that there is no coolant circulation, (i.e. a broken water pump belt, no coolant in the engine).
Ideally a person will want to leave the engine running and slowly and carefully spray water from a garden hose ONTO the radiator until the top hose gets soft. This will cool off an engine QUICKLY but not TOO QUICKLY.
Turning off a smoking hot engine is the second worst thing a person can do, with the worst thing being to simply keep driving. When a hot engine is turned off it gets HOTTER.
The other thing I want to say is that I think the "temperature probes" sold with electric fans SUCK. If I have to run an electric fan I use a proper OEM style switch threaded into the manifold to activate the fan. I used one of those cheap *** probes once when I was a dumb kid, they are CHEESY and they just suck.
Third if the fan is not coming on then it is broken and needs to be fixed.
oh, and just for the sake of KNOWING, change the thermostat. This is cheap and easy and will all but eliminate this as a cause, probably wishful thinking.....
Ideally a person will want to leave the engine running and slowly and carefully spray water from a garden hose ONTO the radiator until the top hose gets soft. This will cool off an engine QUICKLY but not TOO QUICKLY.
Turning off a smoking hot engine is the second worst thing a person can do, with the worst thing being to simply keep driving. When a hot engine is turned off it gets HOTTER.
The other thing I want to say is that I think the "temperature probes" sold with electric fans SUCK. If I have to run an electric fan I use a proper OEM style switch threaded into the manifold to activate the fan. I used one of those cheap *** probes once when I was a dumb kid, they are CHEESY and they just suck.
Third if the fan is not coming on then it is broken and needs to be fixed.
oh, and just for the sake of KNOWING, change the thermostat. This is cheap and easy and will all but eliminate this as a cause, probably wishful thinking.....
Last edited by JMD; May 4, 2010 at 10:16 PM.
4th Gear Member
Joined: Jun 2006
Posts: 1,246
From: Upland, California
For starters an electrical fan temp switch is much better when installed on the manifold rather than the radiator. And also an override switch is a good idea to install for this reason of not kicking on.
6th Gear Member
Joined: May 2009
Posts: 5,232
From: PA
More wiring. Hmmm… How about an nice clutch fan?
5th Gear Member
Joined: Apr 2007
Posts: 2,100
From: Texas Hill Country
Let me just say, I LOVE my big block 19" flex fan.
It takes a big man to back pedal. It is a strange issue but I would concentrate on why the fan is not coming on when the temperature of the engine obviously requires it. Hopefully a bypass will fix your overheating, burping, and pressure issues, so you can then throw your E-fan away and go back to the old school mechanical fan
. Good luck and keep us updated so we can learn.
It takes a big man to back pedal. It is a strange issue but I would concentrate on why the fan is not coming on when the temperature of the engine obviously requires it. Hopefully a bypass will fix your overheating, burping, and pressure issues, so you can then throw your E-fan away and go back to the old school mechanical fan
. Good luck and keep us updated so we can learn.
Last edited by urban_cowboy; May 5, 2010 at 09:27 AM.
3rd Gear Member
Joined: Aug 2006
Posts: 886
From: North East Texas on the Red River
I preface what I am about to say by pointing out that I have only perused this thread without studying every word.
That said, as I went through the thread I kept looking at the engine picture (great looking engine by the way.) I can not see the corner of the head gasket at the front lower corner that you are supposed to see if the head gasket is on correctly.
My $0.02,
That said, as I went through the thread I kept looking at the engine picture (great looking engine by the way.) I can not see the corner of the head gasket at the front lower corner that you are supposed to see if the head gasket is on correctly.
My $0.02,
4th Gear Member
Joined: Mar 2009
Posts: 1,110
From: NJ
I stayed away after accusing the fan, but still like my choice of going back to the clutch fan. I don't like the radiator probe mount sensors either and mine is screwed into the manifold right behind the t-stat... that is "if" I wanted to use it again.
Thread Starter
2nd Gear Member
Joined: Aug 2009
Posts: 476
From: NH
MORE INFO:::::
Its not the fan, I just tested it (hard wired on all the time) The fan was doing its job keeping the radiator cool to the touch at operating temp.
NEW REVEALATION:::
Top radiator hose is warm while the lower is HOT....could I have put in the wrong waterpump? Are any pumps setup to turn the oppisite direction that bolt to a 289 front plate.
Is there anything else you guys can think of that would cause the heat to be building up in the lower hose???
This thing is whacked out.
Its not the fan, I just tested it (hard wired on all the time) The fan was doing its job keeping the radiator cool to the touch at operating temp.
NEW REVEALATION:::
Top radiator hose is warm while the lower is HOT....could I have put in the wrong waterpump? Are any pumps setup to turn the oppisite direction that bolt to a 289 front plate.
Is there anything else you guys can think of that would cause the heat to be building up in the lower hose???
This thing is whacked out.