By-passing the Heater Core

[Moparman01]

Still fighting a nagging over heating issue in my 69 Charger, 440/727, and thru proccess of elimination i want to try by-passing the heater core, worth a shot anyways. Just to make sure, it's as simple as just looping a piece of hose over the 2 ports off the water pump, correct? I don't want to screw it up any more so i figured i'd ask first.

For the record, i have a re-cored 3 core 26 inch Chyrsler radiator, new Mancini water pump and housing, large 6 blade fan and a shroud, tried 3 or 4 different t-stats (160* and 180*) with curently a 160* t-stat., a couple different rad. caps, 2 different after market temp guages plus the stock guage, and i've played with the timing both ways, more retarded more advanced, still over-heats, and finally the engine was in a friends of mine's car before i installed it into mine and it did not over heat! I'm baffled, gonna try the by-passing thing now, see what happens...thanks for the help.

[terrible one]

Yeah that will work just fine.

If you wanted a cleaner solution, I just went and got some allen headed plugs from the fastener store to thread in place of the heater hose nipples. $3 or so and looks a lot better to me.

[ODZKing]

Yeah that will work just fine.

If you wanted a cleaner solution, I just went and got some allen headed plugs from the fastener store to thread in place of the heater hose nipples. $3 or so and looks a lot better to me.

T-O, can you snap a couple pics of that sometime and post them?   

[62 Max]

By-passing the heater core won't solve your problem.

[russg]

By-passing the heater core won't solve your problem.

agree.. the heater can actually be used to help with cooling down the engine if you crank it

[alcusswhen]

Still fighting a nagging over heating issue in my 69 Charger, 440/727, and thru proccess of elimination i want to try by-passing the heater core, worth a shot anyways. Just to make sure, it's as simple as just looping a piece of hose over the 2 ports off the water pump, correct? I don't want to screw it up any more so i figured i'd ask first.

For the record, i have a re-cored 3 core 26 inch Chyrsler radiator, new Mancini water pump and housing, large 6 blade fan and a shroud, tried 3 or 4 different t-stats (160* and 180*) with curently a 160* t-stat., a couple different rad. caps, 2 different after market temp guages plus the stock guage, and i've played with the timing both ways, more retarded more advanced, still over-heats, and finally the engine was in a friends of mine's car before i installed it into mine and it did not over heat! I'm baffled, gonna try the by-passing thing now, see what happens...thanks for the help.

I don't see anywhere that you did a pressure test on the cooling system. You may have something as a header bolt seeping, you can eliminate everything and find the problem with three simple tests. Remove the cap and start the engine when the T stat opens look for bubbles, if you have bubbles you have a head gasket problem. Let it cool off and pressure test heater hooked up, if it losses pressure by pass the heater and test again, if pressure holds replace core if it don't keep the pressure on until you find the leak.

[Moparman01]

Still fighting a nagging over heating issue in my 69 Charger, 440/727, and thru proccess of elimination i want to try by-passing the heater core, worth a shot anyways. Just to make sure, it's as simple as just looping a piece of hose over the 2 ports off the water pump, correct? I don't want to screw it up any more so i figured i'd ask first.

For the record, i have a re-cored 3 core 26 inch Chyrsler radiator, new Mancini water pump and housing, large 6 blade fan and a shroud, tried 3 or 4 different t-stats (160* and 180*) with curently a 160* t-stat., a couple different rad. caps, 2 different after market temp guages plus the stock guage, and i've played with the timing both ways, more retarded more advanced, still over-heats, and finally the engine was in a friends of mine's car before i installed it into mine and it did not over heat! I'm baffled, gonna try the by-passing thing now, see what happens...thanks for the help.

I don't see anywhere that you did a pressure test on the cooling system. You may have something as a header bolt seeping, you can eliminate everything and find the problem with three simple tests. Remove the cap and start the engine when the T stat opens look for bubbles, if you have bubbles you have a head gasket problem. Let it cool off and pressure test heater hooked up, if it losses pressure by pass the heater and test again, if pressure holds replace core if it don't keep the pressure on until you find the leak.

You're right, i have not done a pressure test yet. Actually i'm taking the car over to a buddy's shop next week and we're gonna pressure check it. It's not far so it the car will make it before it get's too hot. I do have a slight anti-freeze leak right at the upper hose water neck/t-stat housing, it seeps out from around the gasket even tho i used plenty of sealer when i put it together. It's not a gush or anything, more like a weep. That could be my problem?? I must stress this, i can start the car and let it idle all day long in the driveway and it will NOT over-heat, gauge won't get more than about 170* in fact!! But put it in gear and head down the road and the temp steadily rises, farther i go hotter it gets! I've pulled into shows with the temps at 230* before, i've gotten to know how far i can drive it before i have to head back to the garage, not fun. As for a head gasket issue, wouldn't that show up in both how the car runs and in the exhuast?? Car runs really strong, i'm also running stock HP manifolds and not headers so the under hood temps should be a bit cooler in theory. Spark plugs look pretty good so i don't think it's running to lean, and the timing is set at 10*. Frustrating....

[terrible one]

Yeah that will work just fine.

If you wanted a cleaner solution, I just went and got some allen headed plugs from the fastener store to thread in place of the heater hose nipples. $3 or so and looks a lot better to me.

T-O, can you snap a couple pics of that sometime and post them?   

Here you go man. Sadly, they look a lot worse after towing it across the country in the rain and I need to paint them, but you get the idea. 

[oldcarnut]

I didn't see anything mentioned about the radiator hoses so do you have a spring in the bottom hose to keep it from collapsing as you drive it faster? If not, it's something to look for.

[Moparman01]

I didn't see anything mentioned about the radiator hoses so do you have a spring in the bottom hose to keep it from collapsing as you drive it faster? If not, it's something to look for.

Yes, i just put a brand new lower rad. hose in and made sure it had a spring in it, i forgot to mention that.

[b5blue]

Timing set at 10*......Try adding more....check advance action also (depends on your set-up but go to 14*) 

[BigBlackDodge]

Maybe a higher t-stat would keep the coolant in the radiator a bit longer giving it more time lose heat?

BBD

[AmadeusCharger500]

I'm curious about the idea of a normal flow thermostat. Where all 4 thermostats normal or high flow?

[62 Max]

I'm curious about the idea of a normal flow thermostat. Where all 4 thermostats normal or high flow?

The high flow thermostat everyone talks about is the Robert-Shaw thermostst that Chrysler used in everything as original equipment since the 50's.

[alcusswhen]

Still fighting a nagging over heating issue in my 69 Charger, 440/727, and thru proccess of elimination i want to try by-passing the heater core, worth a shot anyways. Just to make sure, it's as simple as just looping a piece of hose over the 2 ports off the water pump, correct? I don't want to screw it up any more so i figured i'd ask first.

For the record, i have a re-cored 3 core 26 inch Chyrsler radiator, new Mancini water pump and housing, large 6 blade fan and a shroud, tried 3 or 4 different t-stats (160* and 180*) with curently a 160* t-stat., a couple different rad. caps, 2 different after market temp guages plus the stock guage, and i've played with the timing both ways, more retarded more advanced, still over-heats, and finally the engine was in a friends of mine's car before i installed it into mine and it did not over heat! I'm baffled, gonna try the by-passing thing now, see what happens...thanks for the help.

A head gasket leaking between a cylinder and a water port will not effect the way the car runs and seldom does enough water leak back to the cylinder when the engine is shut down to notice on start up. What happens is cylinder pressure at ignition pushes hot gases into the water jacket over pressurizing the cooling system. It pushes the cap off its base to release pressure in turn causing the coolent to boil [run hot]. When the leak first starts it wont over heat at idle but a time will come when it does. The #1 culprit you have right now is the T stat housing leak. You must repair it to know anything, hell it may be your whole problem. "leak=no pressure=water boils=engine runs hot"

I don't see anywhere that you did a pressure test on the cooling system. You may have something as a header bolt seeping, you can eliminate everything and find the problem with three simple tests. Remove the cap and start the engine when the T stat opens look for bubbles, if you have bubbles you have a head gasket problem. Let it cool off and pressure test heater hooked up, if it losses pressure by pass the heater and test again, if pressure holds replace core if it don't keep the pressure on until you find the leak.

You're right, i have not done a pressure test yet. Actually i'm taking the car over to a buddy's shop next week and we're gonna pressure check it. It's not far so it the car will make it before it get's too hot. I do have a slight anti-freeze leak right at the upper hose water neck/t-stat housing, it seeps out from around the gasket even tho i used plenty of sealer when i put it together. It's not a gush or anything, more like a weep. That could be my problem?? I must stress this, i can start the car and let it idle all day long in the driveway and it will NOT over-heat, gauge won't get more than about 170* in fact!! But put it in gear and head down the road and the temp steadily rises, farther i go hotter it gets! I've pulled into shows with the temps at 230* before, i've gotten to know how far i can drive it before i have to head back to the garage, not fun. As for a head gasket issue, wouldn't that show up in both how the car runs and in the exhuast?? Car runs really strong, i'm also running stock HP manifolds and not headers so the under hood temps should be a bit cooler in theory. Spark plugs look pretty good so i don't think it's running to lean, and the timing is set at 10*. Frustrating....