beating a dead horse....cooling system issue

[340duster]

hey guys hope to pick your vast surplus of knowlage , I have a 1967 Coronet with a fresh 383 4bbl , 727 , 355sg , tti dual exhuast , running 9.75-1 comp , a lunati voodoo cam "302" .475/.495 lift 262/268 duration, performer rpm intakeand a holley 670 vac sec. the temps seem high 210F-230F , I have read a couple threads and have a good idea which way to go . I have already installed the lower rad hose spring , and changed from a 180'f hi flow to a standard flow 160'f t/stat , some but not much change , it still has the original rad it appears to be very wide not sure how many cores but it is twice as thick as the one in my duster , I installed a new napa waterpump when the motor was built , I have installed a large electric cooling fan (I know likely culprit) which I have had good luck with in the past on my non mopar projects. I have also added two bottles of coolant additive (purple ice)

so I will be sending the rad out for a flush and likely sourcing a clutch fan and shroud.... any recommendations for brand type or manufacturer :icon_confused:

 

[tpodwdog]

aaaaaaaaaaaaaaaaahhhhhhhhhhh.........the ever famous and frequently asked..." WHY IS MY CAR RUNNING HOT" question. you car is running hot from one or a combination of these things:

1. clogged radiator
2.stuck CLOSED t-stat.
3.broken water pump.
4.newly built TIGHT engine components
5.ELECTRIC FANSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS

i have answered this question that has plagued mankind since the advent on the internal combustion engine SO many times...i will start to hand out flyers. but i digress and will answer your question to the best of my ability.

first off...your engine is new and TIGHT....tightness produces friction therefore and thus produces heat. this will subside eventually once broken in.

2ndly....195 to 210 is perfect operating temperature. if it stays at 230, and dont climb any higher, ...i wouldn't worry that much. after 500 miles,,,,ID WORRY .

3rdly... the t-stat HAS NOTHING TO DO WITH HOW HOT YOUR ENGINE WILL RUN . a 160 t-stat will BEGIN to open at 160 degrees....a 180 t-stat will BEGIN to open at 180 degrees...and so on and so forth.

4thly....your radiator is the culprit..... a 2 or 3 core rad will cool better than a 4 core.WHYYYYYYYYY ????.... because air moves easier with less restriction....2 cores....less restriction....4 cores ,,,,MORE restriction. opposite of what one may think.

5thly... speaking of restriction.....YOURE RIGHT...that electric fan blocks air flow...plain and simple and i cant put it any other way....get rid of it and put on a flex fan or the stock 7 blader.

once broken in your engine should begin to run a bit cooler with all of the cooling system components in good working order. DONT COUNT ON FACTORY GAUGES FOR ACCURACY!.....get a good aftermarket temp gauge if you dont already have one.....and an OIL GAUGE.....these are the 2 most important gauges you can have.

after your rad has been taken care of see if it runs any cooler. if it dont,,,,get a champion aftermarket rad. not a ton of money and theyre a quality product. my guess is that your radiator is clogged or partially clogged in conjunction with the tight engine.

i have a stock 383 in my road runner,,,and a HOPPED UP HYPO'ED 440 in my belvy...and they BOTH run at 195. 220 is tolerable,,,240 and up ,,,SHUT 'ER DOWN .

...hope i was of some service to you !

 

[Revhendo]

aaaaaaaaaaaaaaaaahhhhhhhhhhh.........the ever famous and frequently asked..." WHY IS MY CAR RUNNING HOT" question. you car is running hot from one or a combination of these things:

1. clogged radiator
2.stuck CLOSED t-stat.
3.broken water pump.
4.newly built TIGHT engine components
5.ELECTRIC FANSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS

i have answered this question that has plagued mankind since the advent on the internal combustion engine SO many times...i will start to hand out flyers. but i digress and will answer your question to the best of my ability.

first off...your engine is new and TIGHT....tightness produces friction therefore and thus produces heat. this will subside eventually once broken in.

2ndly....195 to 210 is perfect operating temperature

3rdly... the t-stat HAS NOTHING TO DO WITH HOW HOT YOUR ENGINE WILL RUN . a 160 t-stat will BEGIN to open at 160 degrees....a 180 t-stat will BEGIN to open at 180 degrees...and so on and so forth.

4thly....your radiator is the culprit..... a 2 or 3 core rad will cool better than a 4 core.WHYYYYYYYYY ????.... because air moves easier with less restriction....2 cores....less restriction....4 cores ,,,,MORE restriction. opposite of what one may think.

5thly... speaking of restriction.....YOURE RIGHT...that electric fan blocks air flow...plain and simple and i cant put it any other way....get rid of it and put on a flex fan or the stock 7 blader.

once broken in your engine should begin to run a bit cooler with all of the cooling system components in good working order. DONT COUNT ON FACTORY GAUGES FOR ACCURACY!.....get a good aftermarket temp gauge if you dont already have one.....and an OIL GAUGE.....these are the 2 most important gauges you can have.

after your rad has been taken care of see if it runs any cooler. if it dont,,,,get a champion aftermarket rad. not a ton of money and theyre a quality product. my guess is that your radiator is clogged or partially clogged in conjunction with the tight engine.

i have a stock 383 in my road runner,,,and a HOPPED UP HYPO'ED 440 in my belvy...and they BOTH run at 195. 220 is tolerable,,,240 and up ,,,SHUT 'ER DOWN .

...hope i was of some service to you !

I agree on most points except the flex fan. I'm not a huge fan of them things. (Yeah, you can go with the pun intended). There are two reasons I don't recommend them, even though I do occasionally use them because of some other issues. The first is that a flex fan at speed can actually flare out and block airflow. (It's the same theory as to why prop aircraft can't go supersonic). The second reason is under rapid decceleration the fan blades can actually flare forward and if your running a really tight space you can contact the radiator.
And recommended reading.....
http://www.forbbodiesonly.com/moparforum/showthread.php?t=34967

 

[tpodwdog]

I agree on most points except the flex fan. I'm not a huge fan of them things. (Yeah, you can go with the pun intended). There are two reasons I don't recommend them, even though I do occasionally use them because of some other issues. The first is that a flex fan at speed can actually flare out and block airflow. (It's the same theory as to why prop aircraft can't go supersonic). The second reason is under rapid decceleration the fan blades can actually flare forward and if your running a really tight space you can contact the radiator.
And recommended reading.....
http://www.forbbodiesonly.com/moparforum/showthread.php?t=34967

i would agree with your points Rev...but i have never personally encountered those things. altho my flex fan on my 440 is louder than the pipes......maybe ill get a 7 blader on it!

 

[Revhendo]

i would agree with your points Rev...but i have never personally encountered those things. altho my flex fan on my 440 is louder than the pipes......maybe ill get a 7 blader on it!

LOL, yeah, they can make themselves known. I put a 7 blade fixed fan on a car one time to disprove a cooling problem and that thing sounded like a Cessna on take off.

 

[340duster]

You guys are great....no turbo lag here I have a pretty good understanding of the cooling system ( though the air flow thru the 4 core versus 2or3 , I didn't think of) I know that the friction of a new build can be of concern but running down the hiway the temp seems a little high , which leads me to blame the electric fan as blocking some air flow .
I was hoping that with the 160' t/stat that I would be making use of the extra capacity earlier ( I do know that at op/temp the t stat takes itself out of the equation other than restricting flow)
I took it for about a 30min drive today in +20c/70'f, and had temps around 230f (autometer gauge) and 20-25psi oil pres hot at idle . bypasses the radcap and fills the overflow container (a 700ml pop bottle) I havedrained the rad by the petcock , flows out fast and free very clean coolant . i will take it to the rad shop for inspection and cleaning , or should I just get a new 2 core or 3 core and nobody seems to be on the clutch fan side so far .

I so glad you all can put up with the same old questions asked by us who try to research all previous related threads but get pulled into some other mopar mysteries and informational posts .....:headbang::hello2:

 

[340duster]

ok so after more research I think the 7 blade fan you guys refer to is a clutch fan , I also looked into champion rads they seem decent , I am leaning towards the 3 core cause I might be just over the 400hp mark once broke in and final tuned , I checked with my local napa parts and they did not have a fan and clutch listed for a 67 but had a listing for a 69 , but a 6 blade clutch fan assembly is that going to be adequate ......

also what is the best shroud that is readily available , black prefered but I can live with chrome too ....

thanks again :blob1:

 

[5.7 hemi]

Timing?

 

[340duster]

16' initial , jumps to 24' with vac adv. and 36' at 2500RPM
i was thinking of slowing the advance curve to have it all in by 3000RPM

 

[Revhendo]

16' initial , jumps to 24' with vac adv. and 36' at 2500RPM
i was thinking of slowing the advance curve to have it all in by 3000RPM

That's a bit aggressive. You are probably on track with dialing that down a bit. You've checked for vacuum leaks and whatnot?

 

[340duster]

doesnt seem to be any vacuum leaks , just running hot on the highway , which i now believe to be from the 4core rad (some build up can be seen on the tubes when looking into the cap opening) and I am going to take it to the rad shop tomorrow , but usually they try to talk you out of flushing as the sludge is likely sealing up some pinholes etc....plus then they get you for a recore.... but I think that the money would be better spent on one of those champion 3 core rads but because of what I have read here I am unsure about their twin fan set up and I am looking into a clutch fan and shroud ....

I can source a 6 blade clutch fan but dont know where to find a GOOD shroud:eusa_think:

 

[Revhendo]

doesnt seem to be any vacuum leaks , just running hot on the highway , which i now believe to be from the 4core rad (some build up can be seen on the tubes when looking into the cap opening) and I am going to take it to the rad shop tomorrow , but usually they try to talk you out of flushing as the sludge is likely sealing up some pinholes etc....plus then they get you for a recore.... but I think that the money would be better spent on one of those champion 3 core rads but because of what I have read here I am unsure about their twin fan set up and I am looking into a clutch fan and shroud ....

I can source a 6 blade clutch fan but dont know where to find a GOOD shroud:eusa_think:

Can't help you on the shroud, but I ran my 440 without a shroud and it stayed at 190 all day long with a Champion radiator.

 

[moparmarks]

Your old radiator is probaly most of the problem and sounds like your on it. Might kick your timing down abit.
I myself don't like flex fans and don't like electric fans on the street. Get a visious fan with a clutch and shroud.
I live in the high desert. My 72 Sat has a 440 auto w/ new 3 core 26" radiator. It can it idle all day in 100* heat and never gets off 185*. Can run at 75 mph all day in 100-110* heat and maybe gets to 190-195*

 

[Revhendo]

And remember, if you don't beat a dead horse the meat will never be tender enough to chew through.

 

[tpodwdog]

i dont think you need a clutch fan. just a 7 blade stationary mounted fan will do.......and a good radiator !. im not a big believer in fan shrouds either but use your own discretion on that. neither of my mopars have fan shrouds and run at a nice 195 no matter how hot or cold it is outside!

 

[coloradodave]

You can get a reasonably priced shroud from Mancini; ditto on the fan and clutch unit. I bought my aluminum radiator, shroud and fan from them and am very happy with the service and products.

 

[daredevil]

Theres a reason the manufacturer installed shrouds. Without one at idle the air is sucked from everywhere and not neccesarily thru the radiator.Down the highway a clutch keeps thefan from fighting incoming air.Retarded timing can make them run hot and lean jetting also.I like the biggest radiator that will fit with two rows of 1 inch or 1.25 inch tubes. Extra spent on a quality radiator beats fried rings, blown head gaskets and cracked heads. Dont play with cooling.

 

[340duster]

Thanks for all the support , I have ordered one of the Champion 3core aluminum 26 inch rads , an oem style shroud and a clutch fan with 7 blades ,the rad shop inspected my original 22 inch unit and said it was partially plugged but could be rebuilt at almost twice the price..... I am also going to slow down the advance slightly , other wise the car seems to be coming together nicely .... mopar or nocar .....I let you know how it all works when it gets here , it going to be a long 7-10 days of shipping and handling :confused5:

 

[moparmarks]

You want to test out your cooling system then come to CO and climb a 7% grade at 75 mph in 85* heat at 10000'.
Mopar stated that thier best cooling setup was a Visious fan with a clutch and a shroud. GM knew this too.
Why use power to spin the fan when not needed such as at highway speeds?

 

[moparmarks]

Thanks for all the support , I have ordered one of the Champion 3core aluminum 26 inch rads , an oem style shroud and a clutch fan with 7 blades ,the rad shop inspected my original 22 inch unit and said it was partially plugged but could be rebuilt at almost twice the price..... I am also going to slow down the advance slightly , other wise the car seems to be coming together nicely .... mopar or nocar .....I let you know how it all works when it gets here , it going to be a long 7-10 days of shipping and handling :confused5:

You did good cricket.