quick overheat

[biginch=bigfun]

Freshly rebuilt 440 bored 30 over. In about ten minutes of run time at idle the car will climb past 220 degrees!

My set up:
1977 440 w/ fresh 452 heads, whiplash cam 9.5 to 1 cast pistons. Stant 160 therm., aluminum high flow water pump in a stock cast housing, Edelbrock preformer intake w/ a thermoquad 850. stock distributer hooked to a msd blaster coil & 6al. Cast iron factory "headers".
My radiator is a 26" Northern aluminum 3 core cross flow w/ no trans. cooler running through it. The fan is a Vergo electric (don't recall the cfm but it is the largest they sell), hooked to a toggle switch. I have run clutch fan but got the same results.

What i have observed:
new mechanical gauge rises fast & seems that it would continue to if i left it running.
with the cap off coolant is passing through the cores freely.
no hose colapse, top is aluminum & bottom has a spring.
it boils when shut off & the radiator will be low by a couple inches even though there is a recovery bottle.
my plugs look like brand new, no signs of lean conditions yet.
the car will start again while hot.

Another problem that arose that I'm not sure if its related is. First my amp gauge puked out, so I by passed it by moving the wire from the fuseable link side to the alternator post. Then the next day while i had the car running my bulk head had minor smoke! the alternater connection in the bulk head melted the plastic. I was planning to run a new wire from the alt. to the back of the gauge.

I'm sure I've missed pointing out something in my setup but my mind is a little fried after several days of this fun! So i figured i'd ask for help & a fresh set of ideas.

Thanks in advance to all the great peopl on this board!!!
Louis

 

[Sweet5ltr]

Freshly rebuilt 440 bored 30 over. In about ten minutes of run time at idle the car will climb past 220 degrees!

My set up:
1977 440 w/ fresh 452 heads, whiplash cam 9.5 to 1 cast pistons. Stant 160 therm., aluminum high flow water pump in a stock cast housing, Edelbrock preformer intake w/ a thermoquad 850. stock distributer hooked to a msd blaster coil & 6al. Cast iron factory "headers".
My radiator is a 26" Northern aluminum 3 core cross flow w/ no trans. cooler running through it. The fan is a Vergo electric (don't recall the cfm but it is the largest they sell), hooked to a toggle switch. I have run clutch fan but got the same results.

What i have observed:
new mechanical gauge rises fast & seems that it would continue to if i left it running.
with the cap off coolant is passing through the cores freely.
no hose colapse, top is aluminum & bottom has a spring.
it boils when shut off & the radiator will be low by a couple inches even though there is a recovery bottle.
my plugs look like brand new, no signs of lean conditions yet.
the car will start again while hot.

Another problem that arose that I'm not sure if its related is. First my amp gauge puked out, so I by passed it by moving the wire from the fuseable link side to the alternator post. Then the next day while i had the car running my bulk head had minor smoke! the alternater connection in the bulk head melted the plastic. I was planning to run a new wire from the alt. to the back of the gauge.

I'm sure I've missed pointing out something in my setup but my mind is a little fried after several days of this fun! So i figured i'd ask for help & a fresh set of ideas.

Thanks in advance to all the great peopl on this board!!!
Louis

I'd say, don't count your water pump out. I would install a factory heavy duty (a/c) unit and see the results. With an electric fan/mech. Combo you should be fine. If you're running one or the other, then that could be an issue. I run the same radiator (summit rebranded), 575HP setup, with a 160* thermostat and run 155-160 driving, 185 max at idle. I use the factory hd water pump on an aluminum housing with 14* initial timing. Factory mech fan/no clutch and electric pusher at idle.

 

[ChgrSteve67]

Few questions

1. Do you have a radiator shroud or did you have one when you fan the mech fan/clutch setup?

2. Does the car run hot when you are driving at freeway speeds?

If not does it start getting hot as soon as you slow down and/ or stop?

 

[Sweet5ltr]

Few questions

1. Do you have a radiator shroud or did you have one when you fan the mech fan/clutch setup?

2. Does the car run hot when you are driving at freeway speeds?

If not does it start getting hot as soon as you slow down and/ or stop?

Pictures would be a great help as well. Good point on number two, if he isn't overheating while driving; could be a blockage or airflow issue at idle.

 

[70rr-brian]

Sounds like you got a big air bubble in the system and it needs burped. Just let it run with cap off for a while....dont let it get too hot like 235ish until the coolant level drops. Run it at about 1500 to 2k rpms...or a fast idle.

Since its your mechanical gauge you are looking at and not the factory gauge then I would think your wiring problem (comes standard on 40 yr old mopars) is unrelated.

 

[racer9190]

yep...check the water pump... I've had two bad "new" water pumps in the last couple months...the pressed propeller backs off and meets the pump housing and the shaft spins inside the prop and the prop doesn't turn as fast as the shaft does anymore...will still circulate water but not fast enough...and eventually stops turningn it all together...also make sure you have burped all the air out...I have air-locked the cooling system before...especially with a thermostat in it... Also never run a wire direct from the alt to the gauge, if you do make sure you run a fusable link in line...it's a good way to burn your hot rod to the ground if you don't have a fusable link in the dash hot wire... I learned that lesson the hard way at a very early age...about 25 years ago.

 

[Sweet5ltr]

Me and my father air locked our engine when we initially put it in, we were dumbfounded for awhile until we figured it out! Can be a simple solution to what looks like a complicated problem.

 

[HEMI-ITIS]

My guess is a bad thermostat:icon_bounce::icon_bounce:

 

[ChgrSteve67]

Here is something else I ran into that drove me crazy. I'm throwing this out there the next time if you take your pump out.

There are two waterpumps. One for a AC car and one for a non AC car.
The cars run different size pullys and the water pump spins at two different speeds.

The pump on the right is for a AC car, has more impellers and are smaller in size, spins faster and moves less water. The one on the left is for a non ac car. spins slower, has fewer impellers but are larger to push more water.

What I ran into with these was a water cavitation problem inside the water pump and made my temp gauge read much higher than what it should.

Also if you don't have a infrared temp gun, get one.

Question: have you put a candy themometer in the radiator to see what the water temp of the water comming out of your thermostat is and compare that to the gauge reading. This will also help you test the thermostat to see at what temp it is opening and water starts flowing through the rad.

Start with the easy tests first and document the results before you start taking things apart.

 

[ChgrSteve67]

Can we get a picture of your radiator and fan setup?

 

[MarPar]

my guess would be there is an air bubble or a snot clogging something up somewheres... if the rads boils over, i would think that would mean that the rad fluid is not circulating at all.

edit: fresh 452 heads...could something have gotten into one of the water jackets? did all this start after putting the fresh heads on, or was it happening before??

 

[Revhendo]

Possibly a head gasket on upside down? (Don't know if it matters with BBs). I'm always suspicious of "High Flow" water pumps. They have caused me more trouble than I care to remember. Consider that the coolant has to hang around the hot parts long enough to actually collect the heat and carry it away.

Also, if you drill two 1/8th inch holes in your thermostat, it will help air escape when you are filling your system.

 

[HEMI-ITIS]

Also double check carb jetting & timing:blob1:

 

[biginch=bigfun]

I will try to address everything put up thus far. I am try'n to get my phone & pc to cooperate to add pics of everything anyone wants.
this is a freshly rebuilt engine but I had the same problem with the 383 also. I have only ran the car in the driveway & garage so far, so I don't know if it will run cooler down the road yet. I do not have a shroud on . just an electric fan mounted to the rad. with previous engine I tried a new factory clutch fan...
I examined the pump prior to install & found no signs of contact w/ the housing. I had been using a 180 thermostat & just put in a 160 that I drilled a 1/8th hole in. I filled the cooling system through the opening where the thermostat sits till no more would fit, then the rest through the radiator. I then let the car sit untouched for 3 day with the cap off. when i started the car i could see coolant rushing through the cores into the tank. the coolant level dropped & i topped it off. it burped a few times before i capped it. I do have a recovery tank attached to receive coolant.
I did have the radiator flushed, boiled & tested. the block & heads were tanked & blown out.
I distinctly remember putting the head gaskets on so you could read "TOP" stamped in to the center ears on both banks.
I had someone suggest the problem might be the head gasket water ports are too small & pinching off the flow?! I never knew there were different head gaskets for different years. Anyone have insight to this? The long block is 1977...
I did test my radiator cap tonite & found it pops a lil early (15 instead of 16 psi) & once it pops open it will not reset & hold pressure until it is removed, then reseated?!

I have a fuseable link coming from off the starter relay to the gauge & hte other wire is now attached to the same post to bypass the gauge. Since the bulkhead connection failed I was either going to jun a wire through the bulkhead w/ no breakable connection or just run a wire from the alternater to the battery.

Everyone's input is GREATLY apperciated! hopefully my reply makes reasonable sense. I will get pics post asap!
Thanks,
Louis

 

[Revhendo]

Same problem with the previous engine? Were any parts transferred over from the old bullet to the new one? If that answer is "no", then I am gonna have to say the problem is in front of the bolts holding the fan pulley on.

 

[67 coronet]

if it is overheating that fast,then i would look into timming and or bad stat.could be an air flow issue,but that would have to be one piss poor electric fan.when you say it did the same thing with other motor,could you elaborate on that.did it overheet all the time or just at idle or when going down the road?

 

[ChgrSteve67]

My money is on a air flow problem.
A trip down the freeway or spray the radiator with water will help confirm it.

You could also get some house fans or a blower and direct more air at the radiator and see if the temp comes down (or doesn't go as high since your not on the road yet). The dyno shops use the big commercial fans or blowers.

I had a 16 inch 2500 cfm electric fan on my 26 inch radiator and had the same problem.
I could run down the freeway between 180 and 190 and as soon as I slowed down or stopped it would go up to 220 in nothing flat.

As for the Atl gauge, its the #1 source of car fires. By pass it and install a voltage gauge. Its also better for determining electrical issues anyways.

I took both of my dash power feeds out of the bulk head connector and ran a 10 gauge wire with a disconnect through the firewall. I also ran a 10 gauge wire from my alternator to the positive lead on my starter relay so the alt will charge the battery directly instead of charging it through the dash harness. By passing the alt gauge and not running the power feeds through tthe bulkhead connector is really important if you have upgraded the stock alt to a high output alt. I think my stock alt gauge was only rated for something like 40 amps and the square back alts are around 65 amps. I run a powermaster 75 amp alt now so the electrical modifications are a must.

Hope this helps but always consider the source.

-Steve

 

[ChgrSteve67]

Here is a article on Allpar that might help you out.

Its not exactly what I did but its close and they stay with the stock alt gauge.
They also show the power lead locations that go through the bulk head.
http://www.allpar.com/history/mopar/electrical.html

 

[biginch=bigfun]

the parts used on both engines:
carb
exhaust manifolds
water pump & housing, lower rad. hose
radiator (was boiled & flushed), cap
electric fan.

I do run a 24" squirl cage fan in front of the car like they do on the dyno.

My 383 would stay at thermostat temp on the move but as soon as you stopped the temp would climb.

Revhendo, thanks for say'n in front of the pulley bolts...I've been waiting for the"loose nut behind the wheel" comments! lol It isn't lost on me that I am one of the carry-over parts that might be the problem. Having to ask for help online after exhausting all that I can think of is a knock to my pride... but I'm at a loss.

 

[biginch=bigfun]

try'n to loload a couple pics