Cooling question, running too hot.

[70DartMike]

The car has a 318 with 4 bbl and headers, and a stock 318 radiator. It had a 180* thermostat and for a while wouldn't run any hotter than 185*. Now (I figure since its summerish and hotter out) it's running around 200 - 210* so I changed it to a 160* thermostat but it still is running 200* ish. I would like to run around 180* again. It's not a high HP motor or anything, just a street driver. Any suggestions?

 

[abodyjoe]

is it running warm sitting or running down the road?

what rad is in the car now? shroud on the car?

 

[Eric_S68]

You can try Water Wetter or Purple Ice, should help and it's a simple fix.

 

[70DartMike]

is it running warm sitting or running down the road?

what rad is in the car now? shroud on the car?

It runs warm mainly when sitting at a stop light or idling. Usually when I start driving again it starts to cool off, but lately it will cool off a bit and then stay hot around 200 - 210*.
The number on the rad is 3574 637 and then there is another number that has a pentastar and then 20446 beside it.
And no, no shroud on the car.

 

[abodyjoe]

i think a shroud would definatley help. maybe the rad is partially clogged. how old is the water pump?

 

[mullinax95]

Well I hate it but I did it. I got off early today because of rain and rode up to Griffin. I took my old radiator with me to make sure to get everything squared away (didn't need it). The sales guy Benji Durham is the one that helped me. He said that as soon as they get one of those built for a Mopar that it gets gone before they stock it in the warehouse. They was building one for a Mopar as I was there but it was already spoken for so he couldn't sell me that one... even though he walked into the back just to check and see if he could sneak and sell it to me. But we walked over to his desk and he took down all my info. He said that it will look close to the original type radiator and I could paint it black if I wanted. It will be a 2 core with 1" tubing (400-600 hp) down flow (not cross flow) for $495 + tax OUCH!. I asked if cross flow is better than down flow and he said it doesn't matter one bit. That the only thing changing is the direction of the flow. I always thought the cross flow are better for some reason. I read Griffin FAQ section and it says the same thing. They have also 2 core with 1.25 tubing for I believe it was $595 which is 600+ HP. They are going to have to build it so I asked if they could locate the top tank inlet closer to the middle and he said no problem. He said it will not be directly centered but it will be closer than it was. Oh he asked me what was the car doing and I told him that on the HWY it would get to 210* He told me that if it was getting hot on the HWY that my radiator is too small and if it was getting hot in stop and go traffic that it there is not enough air movement. So in theory I was having both but that's going to change. ok shroud... he told me that 98% (even big blocks) mopars did not have a shroud unless it was AC equipped. So I don't believe our cars suppose to have a shroud but I'm going to try to find one. He told me to try Bouchillon performance (something like that) or bring in a shroud and they will tack on mounting brackets to fit the shroud to the rad. They will make them a little on the wide side so I can center the shroud to the fan after I mount the rad. He didn't say that but I am going to tell him to do that to give me a little room to move the shroud up and down. He said he will call me to pick it up in about a week or so. I hate spending that kind of money but I can't drive my car without it is the way I'm looking at it. Now I've got to find a shroud.

Here is the website http://www.bouchillonperformance.com/FanShrouds.asp

I'm thinking of getting the 22" fan shrould and let Griffin weld some tabs on to make it fit. I just found this a few minutes ago so I'm still brain picking what I really want to do.

http://www.griffinrad.com/

 

[70DartMike]

i think a shroud would definatley help. maybe the rad is partially clogged. how old is the water pump?

I will try draining the rad, is there anything you can flush the rad with?
The water pump is from an 85 318, but I'm not sure if someone changed the water pump from the 318 before I got it or not.

 

[abodyjoe]

he told me that 98% (even big blocks) mopars did not have a shroud unless it was AC equipped.

may be ok on stock motors but when you start making power you want as much air through that rad as possible.

He told me that if it was getting hot on the HWY that my radiator is too small and if it was getting hot in stop and go traffic that it there is not enough air movement.

hope it fixes it for ya.

here was my problem. i put a nice griffin alumn rad in my car 22x19 cross flow 2 row 1" tubes. couldn't keep it cool while sitting. creep over 200* on a 60* day. in a block once i started moving it would drop right to 180* and stay there until i stopped again. big fan and shroud. still creeped up. even tried an electric fan that flowed 3600 cfm. that crapped out 2 hours from home. never again.

so fast forward to a few weeks ago. i have a jack incident and ruin the griffin rad. i go nuts looking for a new rad for it and couldn't get anything fast. i needed it for OC in like 2 days. so i pulled a questionable stock one out of the shed. 2 row copper rad. put a fan i had laying around on and don't have a shroud on it and that ***** runs cooler then the alumn one ever did. only time since i put it in that it hit 200* was on OC and i was idling in traffic for a while getting in tot he harley dealer show. and even then i took it out of gear and reved it to 1200 rpm and the thing just sat at about 196*. the alumn one would keep creeping up even on a slight rev.

 

[abodyjoe]

I will try draining the rad, is there anything you can flush the rad with?
The water pump is from an 85 318, but I'm not sure if someone changed the water pump from the 318 before I got it or not.

theres cleaners out there that you can run. not sure how well they work though. a friend swears by spick and span. ya run it in there for like a week with just a spick and span/water mix.

 

[mullinax95]

may be ok on stock motors but when you start making power you want as much air through that rad as possible.





hope it fixes it for ya.

here was my problem. i put a nice griffin alumn rad in my car 22x19 cross flow 2 row 1" tubes. couldn't keep it cool while sitting. creep over 200* on a 60* day. in a block once i started moving it would drop right to 180* and stay there until i stopped again. big fan and shroud. still creeped up. even tried an electric fan that flowed 3600 cfm. that crapped out 2 hours from home. never again.

so fast forward to a few weeks ago. i have a jack incident and ruin the griffin rad. i go nuts looking for a new rad for it and couldn't get anything fast. i needed it for OC in like 2 days. so i pulled a questionable stock one out of the shed. 2 row copper rad. put a fan i had laying around on and don't have a shroud on it and that ***** runs cooler then the alumn one ever did. only time since i put it in that it hit 200* was on OC and i was idling in traffic for a while getting in tot he harley dealer show. and even then i took it out of gear and reved it to 1200 rpm and the thing just sat at about 196*. the alumn one would keep creeping up even on a slight rev.

Well damn. I don't like the sound of that. I have a 2 core stock rad on it now and it gets to hot. I was at the car show last Sat and there was a lot of aluminum radiators so I thought that is the answer. I'm going to have a mechanical clutch fan and a electric pusher on the front of the rad for back up.

 

[abodyjoe]

hopefully it does the trick for ya. in my case i have the stock 1974 360 in my car and it wouldn't stay cool. i found a 3 core stock rad (shroud fit better then on the aftermarket rads) that i'm going to have recored and i'm putting a MP viscous fan on it. should be able to sit all day and not have the temp move. well hopefully..lol the alumn did cool down fast as hell i can tell ya that.

 

[2 Darts]

Someone said something about crossflow radiators. IMHO, the design itself is no better, and possibly worse than a vertical flow. The crossflow allows the designers to get more radiator fin area under a lower hood line. If there's an advantage to it, that's it.

The thermosiphon effect of the vertical unit is more efficient. As water is drawn through the radiator it cools and naturally settles to the bottom on a vertical radiator. The water pump inlet draws more uniformly cooled water as a result. On the crossflow, the water from the lower tubes is cooler than the water out of the tubes at the top of the radiator. The extra length of the tubes compensates for the inefficiency of drawing less uniformly cooled water into the water pump inlet.

The other thing that is easy to do that improves cooling efficiency is to seal the cooling system and run a coolant recovery system. This purges the air out of the cooling system when hot and sucks in coolant as the system cools. Keep an eye on the recovery vessel during the first few heat/cool cycles because this is when the air purge occurs.

 

[mullinax95]

The other thing that is easy to do that improves cooling efficiency is to seal the cooling system and run a coolant recovery system. This purges the air out of the cooling system when hot and sucks in coolant as the system cools. Keep an eye on the recovery vessel during the first few heat/cool cycles because this is when the air purge occurs.

I plan on doing that also... I had one on another car years ago. If I'm not mistaking the hose has to go into the bottom of the bottle(Summit brand) from the radiator. The top of the bottle has a hose running off of it and is serves as a drain and vent. Is this correct?

 

[yellowdartdave]

As I have said many times...fan shroud, stock A/C fan and fan clutch is the way to go.
Mother Mopar designed the system well.
I can sit in traffic on Brice Rd. and never overheat..even with a .508 cam with the air on.

 

[2 Darts]

I plan on doing that also... I had one on another car years ago. If I'm not mistaking the hose has to go into the bottom of the bottle(Summit brand) from the radiator. The top of the bottle has a hose running off of it and is serves as a drain and vent. Is this correct?

You've got the general idea. However, there are two different hoses needed. Essentially, the of end overflow hose from the radiator needs to be submerged in the overflow container. Some bottles use a hose through the cap, others have a tube molded into the container (a'la Mopar factory installs). The overflow from the bottle is a separate hose from the one that goes to the radiator. This hose should go from the coolant recovery bottle overflow to below the engine bay without dips or loops that will retain coolant. You'd be surprised where bugs will go for water.

The system that I have on the 73 /6 Dart came from an M-body. The bottle is hung behind the radiator support on the passenger side, over the charcoal canister. The canister had to be lowered about an inch for it to fit. (Shoulda pulled the canister mount from the M-body, too.) I route my overflow through a pre-existing hole in the lower radiator support.

 

[mullinax95]

:love7:

You've got the general idea. However, there are two different hoses needed. Essentially, the of end overflow hose from the radiator needs to be submerged in the overflow container. Some bottles use a hose through the cap, others have a tube molded into the container (a'la Mopar factory installs). The overflow from the bottle is a separate hose from the one that goes to the radiator. This hose should go from the coolant recovery bottle overflow to below the engine bay without dips or loops that will retain coolant. You'd be surprised where bugs will go for water.

The system that I have on the 73 /6 Dart came from an M-body. The bottle is hung behind the radiator support on the passenger side, over the charcoal canister. The canister had to be lowered about an inch for it to fit. (Shoulda pulled the canister mount from the M-body, too.) I route my overflow through a pre-existing hole in the lower radiator support.

Here is what I'm talking about. This is on my Dodge Ram. See how the hose goes into the bottom of the recovery tank in which it is covered in fluid all of the time. Then the hose on top of the recovery tank just vents/ drains excessive fluid.

 

[RedFish]

Running hot at idle can be either the radiater or the fan clutch. Look for accumulation of oily dust on the clutch and shaft. Where the oil leaks out the clutch slips.

 

[70Duster440]

Either type of coolant recovery will work. The Summit kind will work fine too. As long as the radiator can draw the coolant back in instead of sucking air it will work. Course, you need a recovery style rad cap too.

I didn't have room for one under my hood so I mounted a Jaz bottle (from Summit) inside the fender. Overflow hose runs down the side of the radiator and then I plumbed a hard line under the frame rail to the fitting on the bottom of the bottle. The top hose on the bottle just vents. My bottle is secured by clamping action to a bumper bracket with brackets I made. So far, it has worked well.

Back to the topic though: a shroud can make all the difference.

 

[2 Darts]

The picture of your Ram's system is exactly what I'm talking about. The recovery bottle is almost the same as mine in the 73.