So I've been trying to chase down an overheating gremlin since I've gotten my Ramcharger on the road. Looking for a little (read: lot) help now.

Here are the basic facts:


I've got a cheapo Equus electronic temperature gauge and am using their sensor.

It is in the 3/8" fitting closest to the water neck in the pump housing.

Thermostat is new (so therefor could be deficient)

I am using a Ford Taurus electric fan. It moves a lot of air, but is not appropriately sized for my 26" radiator. The shroud is about 5-6" too narrow from side to side, and roughly the same from top to bottom. That leaves a rather large area of the radiator unattended. I know this is an issue, but I can't judge just how much of an issue it is.

My timing is currently 14* initial, 40* total. I am not sure when it is all in at.

Upper and lower radiator hoses are new. Upper has a spring in it. Lower does not. At idle, with engine up to operating temp, hoses do not collapse with engine revved.

Carb is an edelbrock 1406 and IMS are set at exactly 1.5 turns out. Exhaust does not burn your eyes out or smell overtly like fuel, but it does have that tell-tale "carbed" smell.

I was doing some freeway driving tonight (65-70 mph) and the temp gauge just kept on climbing. I stopped driving right when it crested 215*. I'm fairly confident it would have continued to rise.

I pulled into the house and let the truck idle for ~15 minutes and it dropped, but never going below 200*

I do not hear any detonation at speed, but it's an open cabin in there without carpet or flooring, so a 440 in those conditions is pretty loud.

When I remove the radiator cap (new Stant 16PSI), I can clearly see fluid moving from the top inlet across, so there is some transfer happening.

Water pump "looked" fine, and is the solid cast edelbrock style.

I'm not sure if it matters, but my heater hose nipples are plugged. I do not have a loop between the two, they are just capped at their outputs.

After continuous driving, if I try and squeeze the upper radiator hose it feels pressurized. Very rigid and firm. If I lift the lever on the radiator cap, I hear a hissing sound coming out of the hose I've got attached to the nipple on the neck of the radiator that is just air. Then the top hose can be squeezed and manipulated.

Even though I've got a hose and hose clamp on the nipple in the middle of the radiator neck leading down near the steering box, there is still usually a small ring of fluid around the bottom of the neck. I'm not sure if this is a leak and not allowing the system to build pressure.

I ran the engine with straight hose water while I was doing some tuning and testing, maybe 2 months, before draining it and going with an appropriate coolant mix. Now, the coolant has a dark green/brownish tint to it, but no oil on the surface of the coolant in the tank.



I'm sorry that was long. I just try to put all the facts that I know out there so some of you felluhs can give me the best answer on where to go from here. I would greatly appreciate it. Thanks for your time

-Pat

You do need a spring in bottom rad hose.When the hose is being sucked close it is at higyway speeds.Which side of the rad do you have the fan mounted on?Fan doesn't matter at highway speed when does it come on what temp?Are you sure your gauge is reading correctly.

I would back the timing off to 34 and give it a shot. Especially if you are running 87 octane pump puke. Also, I'd ditch that little fan and get something that covers the radiator.

How's the radiator? Is it the correct radiator for the 440, and is it clean inside, or is there crud that might be restricting flow?

I had the same issues with my Cuda after rebuilding the 360 in it in 1995. The temp would slowly rise while cruising down the highway, and would level off and slowly drop at idle. I replaced the radiator with a new 2-core radiator, and that helped - I didn't have to pull over to let it cool anymore - but I was still on the ragged edge of overheating on the highway. About a year later, I had an accident that pushed the radiator into the fan, so I opted to upgrade to a 3-core radiator (and had it paid for by the other guys insurance), and I haven't had a cooling problem since.

By the way, I also have a Taurus fan - it seems like a good unit and moves a lot of air. With the 3-core radiator, though, it almost never comes on. I have it set to come on at about 200 - 205 degrees, and the only times it will come on is if I'm in stop and go traffic or idling for a while.

(1) partly restricted stat not opening all the way (toss it for (1) day & check it at highway speed again). (2) inadequate radiator

1 180 Napa super stat
2 factory thermal clutch fan-Ma Mopar knew
3 factory shroud (mega parts $95)
4 royal purple
5 4 row core
6 laser digital for REAL temp

could be timeing and a lean carb

i like to use a vac gauge along with a timeing light

write down your seting and try it a few times at diff setings,adjust curb idle and A/F screws to get highest idle

i know where to set the SB for cheap gas and where to set it for 92 gas and 1/4 mile blast and no pinging



on the rad replacement,have yours flow tested at a red shop,put a recover tank on it and make sure you have the correct cap for a recover system

I like the 3/4 ton HD cooling 3 core rads in all my trucks,tey are taller and thicker

find a 7 bade fan(got mine from a 76 amc hornet) and get a new NAPA HD cooling thermo clutch with the correct fan shroud

you need the spring in the lower hose,you cant see it some time reving it up,but going down the road at sustained rpms it can slowly colapes

with a recov sytem it will push water out of the rad as it expands and suck it back in when it cools down

add a loop on the heater nipples with a flush tee and back flush it add distilled water and water wetter

good luck

My radiator is a new unit I bought from O'Reilly. P/N 433889. A 3 core radiator.

I guess the easiest thing to do today is pull the thermostat out and drive it around for a bit. If I see the temp start climbing again, I'll know I need to look elsewhere, even though I'll still replace it with a new t'stat.

did you flush the block with the core plugs out?

maybe airflow with the fan set up,i would run a stock thermo clutch 7 blade fan stock shroud

is it a stock BB rad?...heavy duty cooling

I know for my 85 SB I swaped in a 86 3/4 ton SB HD rad and shroud thats taller and thicker 3-4 core

i will be getting another for my 440 also

use candy thermo in the top of rad after its warmed up good and check water temps

does it puke water? on shut down

my 440 ran warm when i first got it running,me setting timeing by ear had it way advanced and carb was lean

got it dialed back and the carb adjusted some and idle down to 650-750 rpms

temp is steady at stat 180*

IMO,I would go as much stock set up as I could and ditch an elect fan for cooling

If it was too lean the engine would rattle, especially when the temp got up around 200. Same goes for timing if it was too advanced. The fact it began to cool down when it was idling seems to indicate its a cooling system problem. Since you are not getting a rattle, i'd for sure check the temp gauge. Yes a a pot of boiling water and a meat thermometer can be used but it will be a hassle with an electric gauge and sending unit. I'd try and find a mechanical gauge and use that to check the system. At hwy speeds the fan should have no effect on the temp rising, however, it could if it is actually preventing enough air to pass the system. Its cooloing at idle in the driveway so the fan is working~~~~somewhat. One thing the pot of boiling water can be used for is to check the thermostat. The fact it cooled down to only 200 at idle makes that suspect. First check the actual temp, if the gauge is accurate then second pull the thermostat and check that, if ok then try and verify that nothing is preventing air flow over the radiator. Good luck.

ive been in the radiator repair buissness for over 30 yrs,as i recall the 889 radiator is a 18x26 core ,there used to be a larger radiator available for the bigger engines,it was around a 21x24 core as i recall,at least 3 rows,4 is better,

You need to recurve the distributor. 40 total is too much. An 8 to 1 motor has no quench. 34 would be good, might could run 36.

I ran my car at 38 total and I never heard it ping. Just didn't run as smooth as at 34. Tried 36 and wasn't much different than 38. More than likely it had some silent knock at the higher settings. Back to 34 and it is smooth once again.

3 core might not be doing the job.

Running it on straight water may have started a rust fest in there.

Decided to try and eliminate some of the questionable variables.

Went to the local parts store and picked up a mechanical temp gauge. Brought it home, put it in a pot of boiling water along with one my digital thermometers and it was dead nuts on.

Took it and installed it in the other vacant 3/8 port on the pump housing next to the electric temp sending unit. Went for a quick jaunt down the road. As predicted, electric gauge got up to 210* but mechanical only hit 195. Pulled into the driveway and was able to relieve system pressure and take off radiator cap. Put my thermometer in there about an inch under the coolant level and it read 195*. I'm running a milodon 160* thermostat.

I'm going to try backing down the timing a bit more. At idle, with vacuum unplugged from the dist, I'm getting 12*. I plug in the vacuum line and it jumps to probably 20*. I have my idle set at roughly 800.

Thanks for all the help so far, folks.

Are you running ported or manifold vac?

Sounds like you aren't on the idle circuit if it is on the ported.