• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

OK! so here's another 440 overheating issue.

L

Lenny Arsenault

Well-Known Member
Local time
12:47 AM
Joined
Oct 7, 2011
Messages
192
Reaction score
24
Location
Maine
I also have an overheating issue with my newly rebuilt 440 I took it for its first drive about 5 miles and by the time I got back home it was 230 to maybe 240 degrees. I'm not sure how many blades my fan has will have to check, no clutch, new mopar HP performance water pump, I did disconnect the heater coil, I have a fan shroud, 26" radiator stock, The motor ran fine at the machine shop on the dyno they made a dozen runs with no overheating problems. Not sure how hot the motor gets before a discharge off the Cooling overflow top of radiator to bottle but, I got up to 240 degress or so. I will be checking it out this weekend when I get back home. I thought I would pull the thermostat and see if in fact it works, maybe an air bubble, lower radiator hose see if has the built in spring, try running it without the thermostat to see if this will do anything. Thank
guys! I will let you know what I find. Lenny
 
Those are the big things, I would check lower hose, T stat, check that Radiator for cooling capabilities. My old 26 would hold temp good but after a new build, just seemed to lack the cooling capabilities. I wouldn't run it without a T stat long. My guess is your 26 " might be calcified and a cleaning, or a new alluminum one.

Mike
 
195 t stat is fine, i run one in my rebuilt 440. I drove it all around in 30 degree heat and it never went past 190. I think your problem may be timing related. Also combined with the fact that your engine is new. My 440 got real hot until I ran it a few times. It stopped over heating. If the timing is too retarded it gets hot.
 
Don't run without the thermostat. It is a required orfice that slow down the coolant flow so it has time to soak up the heat from the block. I know they sell restrictor plates that go in the water neck. also check that the fan has enough of the shroud sticking over it for proper airflow.
 
After checking what you already stated I'd suspect the radiator. I have an aluminum radiator with two 1" wide rows, will sit and run for ever at 165-180.
 
You said it ran fine on the dyno, so now that it is in the car, are you using the original in-dash temp gauge, or a high quality(accurate) aftermarket temp gauge. there is roughly 40 degrees difference between my original temp gauge and the autometer I installed.
 
not sure if this has been said, but make sure you have taken the cap off the radiator and let all the air escape on a fresh rebuild. When we first put our 440 together years ago, we didn't do this and couldn't believe it was running hot! Just something really simple that can be really confusing. I run a 160* thermostat as directed by the Direct Connection engine manual, and the car runs 165-180* while driving, may creep up to 190* if sitting in heavy traffic but cools down real good once the thermostat kicks open. but I am running an aftermarket aluminum universal radiator and a jaguar fan clutch and a good, universal fan for clearance. I don't run a fan shroud either.
 
Sweet5ltr said:
not sure if this has been said, but make sure you have taken the cap off the radiator and let all the air escape on a fresh rebuild. When we first put our 440 together years ago, we didn't do this and couldn't believe it was running hot! Just something really simple that can be really confusing. I run a 160* thermostat as directed by the Direct Connection engine manual, and the car runs 165-180* while driving, may creep up to 190* if sitting in heavy traffic but cools down real good once the thermostat kicks open. but I am running an aftermarket aluminum universal radiator and a jaguar fan clutch and a good, universal fan for clearance. I don't run a fan shroud either.
Click to expand...


X2 Bet the dyno shop had a large amount of air flow for those dozen runs. 180° stat for me and run that all day and 195-210 in stop and go. I also run a 1400 cfm pusher in front with a relay set to come on at 210°.
 
180 Superstat from Napa. Get and use a digital laser temp gun to be sure of actual temperature. Keep us posted.
 
Thanks everyone for all the information and suggestions I guess I will not be running without a thermostat as some of you have mentioned not to. Im not sure whats in it but, I will find out friday when I get into it. I have two temp gages working in the car autometer and the original one in dash unit they both showed very hot temperatures . I will giving a try at removing the radiator cap
like Sweet5ltr mentioned and working the bottom hose a little bit. Yes! maybe a new aluminum radiator is in order here also. The timing is set at 16 Inital and 35 advanced do you think this is to much? I had a friend set it for me. Oh! yes I will also post pictures of the new AAR hood scoop installed on the car man that thing looks fantastic.
 
Everyone's timing setup will be slightly different based on their engine combination. 16 advanced may be just right, i adjust mine until it pings and is hard to start when hot. then I back it off until it runs perfect. Too advanced timing could also be a cause of running hot.
 
I want to know what kind of fan is on it. If it's one of those flex fans, it's no good. I'm using an aftermarket 7 blade stainless fan with a 26" 69 RR radiator, and have no issues here in florida.
 
Furyus I believe I have either a 5 or 6 blade fan so looks like I should invest in maybe a 7 blade fan. I used this fan with no shroud and the original water pump on a basicly stock 413 it ran around 160/170 degrees all the time. So what I have here is a new motor,
bored .030" over, added a shroud and changed the water pump with an aluminum HP Edelbrock did not change the original pumpo housing. I am tempted to try and installing a new 7 blade fan with the original water pump back on if I can't find the smoking gun.
What do you think my next move should be? Thanks again for all the responces here.
 
I may have found the trouble a rooky mistake! here I was sure the radiator was clean. It was anything but that when I took off thr radiator cap and looked in I saw what looks like bugs and some sort of white soot. I am going up tom the garage to start taking things apart and see what else may be wrong. thanks Lenny
 
Sorry to divert, but I want to flush my cooling system with an aggressive flush. Local shops won't do it because they don't want to risk mixing red with my green coolant in the machine. What is the best way to renew green coolant in the driveway?

It's about 5 years old, but looks good and the test strips read ok.
 
I'm gonna go simple here. Alot of folks overlook the basics. Have you "pressure-tested" your radiator cap? As coolant heats-up, pressure increases. Yeah, we all know that. BUT, a weak cap can allow a significant amount of coolant to flow to the overflow container. From a quart, to nearly half-a-gallon! Not to mention the lack of pressure lowering the boiling point. Now your cooling system is low on fluid. When you shut her down, the reservoir is drawn back into the system, making you think all is well because you waited till it was not hot to open the cap and check the fluid level. My 97 Ram truck did this in the driveway. After 10 mins of idling, the fluid would start boiling furiously into the overflow. And the temp needle got twitchy. Using a radiator pressure tester with a cap-adaptor, I found my old cap was popping-off at about 13 psi. I replaced it with a new NAPA cap, tested it before installation (solid at 16psi), and have had no troubles since. I'm not saying this is your problem, but check the cheap and easy **** first.
 
That sounds interesting Scotts74birds, maybe I sould invest in a new radiator cap. How did you pressure test your new cap to verify set pressure? When my car overheated it never dumped any coolant to the overflow tank, could the cap be stuck or did the pressure never get that high? I also checked out the fan it is a 6 blade 16" dia. I also found no thermastat in the waterpump machine shop never installed one for some reason. It looks as though a mouse found himself a home inside my radiator over the winter I see seeds and cotton material inside so I am maybe its time for an aluminum radiator but, what one I don't want to spend a weeks pay on one.
 
Lenny, You might try taking your radiator to a local radiator shop and having it boiled clean and pressure tested. Usually a lot cheaper than a new one. Good luck.
 
You must log in or register to reply here.

Similar threads

joew94th
Overheating problem! Help!
2
Replies
38
Views
3K
Darter6
Darter6
W
68 GTX 440 puking AF
Replies
10
Views
709
Jerry Hall
Jerry Hall
jteck10
Fan+shroud part numbers for 26" radiator
2
Replies
27
Views
2K
68 Sport Satellite
68 Sport Satellite
H
OEM fan shroud 68’ Coronet RT
2
Replies
22
Views
1K
Heat-Med
H
Butch Harley
69 roadrunner overheating questions
2
Replies
38
Views
3K
Butch Harley
Butch Harley
Auto Transport Service
Back
Top