coolant mix

[pjm8047]

I was wondering whats a good coolant mix ratio for my 71 rr 383?50/50 seems to boil over and spit out the radiator overflow hose and starts to run hot.its the original radiator. Thanks

 

[hemi#1]

I run a 50/50 mix and add a product called water wetter. 1 bottle. it is supposed to drop the overall temp by 20 deg. we use in our 29 ford pick up dragster. it does help.

 

[73runner]

I was wondering whats a good coolant mix ratio for my 71 rr 383?50/50 seems to boil over and spit out the radiator overflow hose and starts to run hot.its the original radiator. Thanks

50/50 should work fine with no problems. Sounds to me like you may need a new radiator cap, have a bad thermostat, bad lower hose spring, bad fan clutch or a plugged radiator. I would pressure test the cap and flow test the radiator first then work the system back though the "normal" service parts. If it's a true survivor, then you basically have a very old collection of parts any of which are now much older than the original manufacturer ever intended to have in service for so long. Seals go bad, rubber shrinks, glycol evaporates, greases break down, and internals rust. But don't fret too bad, survivor status still let's you do service parts without any loss in value.

I've got a survivor 73 Town and Country with 62,000 miles and have been chasing a rough idle problem since I got it. Turned out to be a burned valve. Killed me to break the heads off. And it kills me to break into anything that is original. But you gotta do what you gotta do to keep it running.... And safe!

If it's not the service parts then it must be the pump..... Or possibly worse... Head leak. Not likely but.... Hey .... Could be worse.

Good luck and keep us posted!

 

[Dennis H]

Green coolant only. 50-50. Check flow and ph. 2" from top no fuller. I too use Purple-Ice to reduce surface tension.

 

[pjm8047]

The radiator cap and thermostat are new.How can i test if the radiator or lower hose is bad?

 

[Xp29h]

Is this heating problem new or been happening for a while? I run 50/50 green coolant with my 383 and it's just fine. See if you can get a pressure tester to see if system is holding right. Then check flow as previously stated. Also, just because they're new doesn't mean they are working correctly. It's a reasonably cheap check to replace with a different style or model ( cap and thermo) I've seen junk right out of he box! Good advice above, think basic issues then work your way up. Good luck.

 

[pjm8047]

This problem started last year on really hot days. I replaced the thermostat and cap at the same time no improvements. I have been running dexcool in it for years .my father flushed the system out and put dexcool in it.Dont ask me why . It was way before my father gave the car to me.thanks of the ideas

 

[Dennis H]

Dexcool has a bad rep. Also use a laser temperature gun to be sure of actual temperature. 200 is not out of range at times and spitting happens when over filled.

 

[pjm8047]

ill top off the radiator but not too much.Is there any way I could test the temp sensor with a dmm?

 

[sleepar]

I would flush the system a few times and drain it from the block threaded plugs on both sides by the oil pan. Those plugs will give a good idea of how mutch crud has accumulated in the block... I have pulled an unbelievable amount of stuff like radiator sodder with wire brush pipe cleaners

 

[Dennis H]

I would flush the system a few times and drain it from the block threaded plugs on both sides by the oil pan. Those plugs will give a good idea of how mutch crud has accumulated in the block... I have pulled an unbelievable amount of stuff like radiator sodder with wire brush pipe cleaners

Not a bad idea. I was surprised when my speed shop (Dito's SSF) said he pulled those out during a routine flush and gave it a clean bill of health.

 

[73runner]

The radiator cap and thermostat are new.How can i test if the radiator or lower hose is bad?

Simple way to test both is to watch the lower hose as you rev the engine ( after it is warmed up, thermostat is open and the system has some pressure). If the lower radiator hose shrinks or collapses when you rev the engine, then the radiator may have a flow problem and the water pump is creating a low pressure vacuum as it pulls against the resistance in the radiator's ability to flow. This low pressure vacuum would then collapse the bottom hose.

In the old days they would put a spring in the lower hose to keep it from doing this under high revs with even a full flowing radiator. But if it's doing this at low revs, you need to pull the radiator out and have it flushed or re-cored.

New hose materials have made the springs obsolete. So don't worry if your replacement doesn't come with a spring.

 

[pjm8047]

So I did a complete coolant flush today and refilled the radiator with a 50/50 mix with a coolant additive as I was doing this I notice alot of lime deposits in the radiator.I drove the car on the highway and the temp gauge reached to first line on the hot side on the gauge.Ive never seen it go thas high.I think I need to invest in a new aluminum radiator.What do you guys think?

- - - Updated - - -

my lower hose has a spring

 

[Dennis H]

Check the temp with a laser gun to be sure. Copper radiator, shroud, clutch fan have never let me down. Ma knew. My pal with a killer 'Cuda said yesterday that he should have gone with the factory system instead of the fancy two-stage electrics etc.

 

[pjm8047]

I dont have a laser gun but i did put a thermometer in the radiators cooling fins and read 180F with engine off after a drive on the highway.