cooling not so cool

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mopar505

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well looks like i got some work to get this mopar to run at normal temps. problem is gradually heats up until coolant overflow.had it dynoed and a tune put on it so were good on A/F ratio and timing. before the tune it would get hot at lights and slow traffic then cool off once in the wind. after the tune it now just gradually rises until pukes coolant. probably about 15 minutes of country road driving. 26" three core factory rad with 6 blade 18" clutch fan (NEW ). shroud is factory. The motor is a new build maybe 50 miles on it. 440 4spd. slightly hotter cam than stock other wise factory specd motor. im guessing 190 t stat? and stock 6 vane pump. Problems i see that need addressed.
1. shroud to radiator has air gaps all around it. need to seal with foam tape
2. fluid looks cruddy, guessing from the dyno pulls it got some junk stirred up. brown rust color. was green before tune.
3. with rad cap off and engine up to temp coolant flow looks inadequate to me?? its moving but im not sure what typical NORMAL flow should look like?
4. big problem here , the fan/shroud combo is not doing ****.it only pulls air thru the very center of rad. every where else its pushing HOT motor compartment air back thru. see video, paper is flopping wrong direction. May need some input on this one. here is what i see. fan blade is 3/4 out of shroud and not centered. there is also a 1" to 1.5" gap from edge of fan blade to edge of shroud. almost like a bigger fan could go in but i think a 20" would hit shroud? heres what i plan to do.
5. drain and remove rad. block flush
6. check thermostat and possibly install a 180
7. pull pump and identify number of vanes and insure no problems
8. seal shroud to rad for air tightness.
9. install a 7 blade 18.5 fan and keep the clutch
10. how about some input on # 4 problem.

**note** cant get iphone 7 vid to upload,any tricks/short cuts
got it.
 
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Here is what I did to my rad, set it down on the driveway with the inlet and outlet pointing up, put the rad cap on and filled it with white vinegar, took about 1 gal. Let it set for a couple hours maybe 3 and drained it out, all kinds of sh*& came out I couldn't believe it, flushed it with garden hose for a while and put it back in and it worked a lot better. The best part is it only cost $2.00
 
my kind of fix, owner labor only. im gonna flush the rad too.
 
Although my cooling issue was different. 205-210* at highway speed. Lower temps at lower speeds. Ambient temp approx 80-90*. Factory shroud, 3 core rad, 7 blade fixed fan. Fan is 1/2 in and 1/2 out of the shroud. New "stock style " 8 vane water pump. 190 tstat.
My timing cover had another coolant leak.(twice in 2 years now).
R n I'd everything. Replaced gaskets, fresh coolant 50-50 mix. New tstat 160*.
Dropped my engine temps a minimum of 30*. I now run AT MOST 175*.
I've read lots on flow, 6 vane vs 8 vane, different temp tstats etc etc. I know I'm babbling but in my situation a tstat fixed it. Your situation might be different.....
Good luck
 
Although my cooling issue was different. 205-210* at highway speed. Lower temps at lower speeds. Ambient temp approx 80-90*. Factory shroud, 3 core rad, 7 blade fixed fan. Fan is 1/2 in and 1/2 out of the shroud. New "stock style " 8 vane water pump. 190 tstat.
My timing cover had another coolant leak.(twice in 2 years now).
R n I'd everything. Replaced gaskets, fresh coolant 50-50 mix. New tstat 160*.
Dropped my engine temps a minimum of 30*. I now run AT MOST 175*.
I've read lots on flow, 6 vane vs 8 vane, different temp tstats etc etc. I know I'm babbling but in my situation a tstat fixed it. Your situation might be different.....
Good luck

does that 8 vane have the backing plate on it? i hate throwing money at ****. in my case i got couple things not right coolant flow and air movement. your fan, is it centered in the shroud side to side and how much of a gap is between the outer edge of blade and edge of shroud?
 
Measure your pulleys. The water pump pulley needs to be smaller than crank pulley. You will also need a high volume water pump. Don't cheap out on a thermostat. Get a Stewart Components thermostat.

You need to clean the radiator. But you have more issues than that.

Also remember that the slower the water pump turns the slower the fan turns.

I don't use a shroud.
 
Measure your pulleys. The water pump pulley needs to be smaller than crank pulley. You will also need a high volume water pump. Don't cheap out on a thermostat. Get a Stewart Components thermostat.

You need to clean the radiator. But you have more issues than that.

Also remember that the slower the water pump turns the slower the fan turns.

.I don't use a shroud.


yes, once i get rad out gonna measure the crank pulley and pump pulley. mancini makes a good high volume pump im looking at. the reverse air movement has got me guessing?? turbulence ?
 
Everything in my situation is stock design, other than alum intake.
67 barracuda 273, 904.
I would estimate I have 3/4" between end of blade and shroud. I can dbl chk if need be.
The new stock style water pump has no plate on the back(I believe).
BUT the issues I have/had with it is the bosses for the alternator and power steering pump were not same dimensions, and still aren't 100%, I had to grind the buggers down in a few spots.
I haven't watched your video yet, I'll chk it out.
I also verified all my temps with heat gun and compared to my Autometer temp gauge.(with in spec).
For the cost of a tstat, what the hell??
does that 8 vane have the backing plate on it? i hate throwing money at ****. in my case i got couple things not right coolant flow and air movement. your fan, is it centered in the shroud side to side and how much of a gap is between the outer edge of blade and edge of shroud?
 
Yeah something wong in that video. I couldn't see the gap between blades and shroud?? Post a pic maybe? Is that a factory shroud? I would do what Brian6pac said with rad, tits up and fill with vinegar. Wish I had done that, although I have flushed/cleaned with powdered laundry detergent.
Also new tstat, labor and $10.
 
Yeah something wong in that video. I couldn't see the gap between blades and shroud?? Post a pic maybe? Is that a factory shroud? I would do what Brian6pac said with rad, tits up and fill with vinegar. Wish I had done that, although I have flushed/cleaned with powdered laundry detergent.
Also new tstat, labor and $10.

factory shroud, will do these things for sure. when its apart im checking everything. nothing more frustrating than doing something twice. When water is involved makes it that much more of a pain and MESS
 
Once I got everything gooped gasketed and buttoned back up. I walked away from it for the night. I then filled up the coolant and leak free, timing cover, rad, front oil pan seal, and tstat. Dry as a bone and 170*.......when it starts....:BangHead: .
Alt, vr or ecu took a **** lol.
Good luck, some good advice here.
 
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A couple things...

You only want about an inch of fan "max" inside the shroud. Many will say 1/2" max.


You might have a timing issue if it now always climbs to overheat, where as before it would cool once in motion from those warm ups while sitting at a light.
Start there and then adjust the fan accordingly. They might have raised the intial but skipped the other end "full advance"and that will have it in an unrecoverable position in no time. I didnt include the cap because if what you said...but it would not hurt to replace it with one 2-4lbs higher rating.

Thats a start, not a guaranteed fix.
 
Running warm, use the back of your knuckles, or these days, a temp gun, and measure the temp of the rad, mid way down, slowly, all the way across.
You'll likely find some cool/cold areas, the more cold tubes, or bigger cold area, the bigger the prob. The cold areas are blocked tubes, not doing their job.
Have the rad rodded out, or re-cored, latest rage is alum.
Use the heat gun to measure the temps at the rad inlet/outlet temp, the rad should lose min 40 - 50*.
Then go take the same readings off your daily driver for comparison.
 
A couple things...

You only want about an inch of fan "max" inside the shroud. Many will say 1/2" max.

This could explain the blowing out the front, as you would be shocked at how much air those blades throw to the sides as well as back toward the motor.
Being too deep in the shroud very well could be forcing a bunch of air forward.
Good call there MOPAROFFICIAL.:D

To the OP

The vinegar in the radiator works pretty well, but don't forget the block itself.
The same vinegar soak and flush also works there, and I'll even drive the car for a couple of hours around doing chores or grocery shopping with the vinegar water mix in it.
My favorite method for flushing a block in the car is to use a water hose and compressed air both at the same time. (and the more air pressure the better on the block flush)
The blast of air along with the water causes a high speed blast of air/water mix to blow through the block WAY faster than the coolant ever travels, and doing it through the stat opening is forcing it backwards of the normal flow so it really carries the junk out.
Put both in your thermostat opening without the stat, wrap a wet towel around the hose and air chuck both and hold it there tight.
Let about 5 seconds of water go in and then hit the air until mostly air comes out the bottom hose outlet of the water pump.
I repeat this about 5-6 times or until I get clear water coming out with each blast.
It works well on radiators as well, but you have to be a little conservative about how much air pressure you use as to not split a cooling tube.
Same with backflushing the heater core since they all share the same cruddy coolant.
 
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This could explain the blowing out the front, as you would be shocked at how much air those blades throw to the sides as well as back toward the motor.
Being too deep in the shroud very well could be forcing a bunch of air forward.
Good call there MOPAROFFICIAL.:D

To the OP

The vinegar in the radiator works pretty well, but don't forget the block itself.
The same vinegar soak and flush also works there, and I'll even drive the car for a couple of hours around doing chores or grocery shopping with the vinegar water mix in it.
My favorite method for flushing a block in the car is to use a water hose and compressed air both at the same time. (and the more air pressure the better on the block flush)
The blast of air along with the water causes a high speed blast of air/water mix to blow through the block WAY faster than the coolant ever travels, and doing it through the stat opening is forcing it backwards of the normal flow so it really carries the junk out.
Put both in your thermostat opening without the stat, wrap a wet towel around the hose and air chuck both and hold it there tight.
Let about 5 seconds of water go in and then hit the air until mostly air comes out the bottom hose outlet of the water pump.
I repeat this about 5-6 times or until I get clear water coming out with each blast.
It works well on radiators as well, but you have to be a little conservative about how much air pressure you use as to not split a cooling tube.
Same with backflushing the heater core since they all share the same cruddy coolant.

in the video, looked like the shroud wasn`t tite against the rad. , the fans blade should have only about 1/2" clearance, unless ur engine moves around a lot. I like 1/4" to 3/8', but my engine doesn't move around at all-----------
Will be testing a thermostat like yr suggested a while back next.
 
A couple things...

You only want about an inch of fan "max" inside the shroud. Many will say 1/2" max.


You might have a timing issue if it now always climbs to overheat, where as before it would cool once in motion from those warm ups while sitting at a light.
Start there and then adjust the fan accordingly. They might have raised the intial but skipped the other end "full advance"and that will have it in an unrecoverable position in no time. I didnt include the cap because if what you said...but it would not hurt to replace it with one 2-4lbs higher rating.

Thats a start, not a guaranteed fix.

i thought about the timing. that would make sense. easy check but tuner said all in at 34 so sounded close to me. with all the crud in the rad from the dyno pulls i was thinking restricted/poor flow thru rad thus the slow heat to boil. ill throw a light on it. the fan is probably 3/4 to 1" in shroud.
 
This could explain the blowing out the front, as you would be shocked at how much air those blades throw to the sides as well as back toward the motor.
Being too deep in the shroud very well could be forcing a bunch of air forward.
Good call there MOPAROFFICIAL.:D

To the OP

The vinegar in the radiator works pretty well, but don't forget the block itself.
The same vinegar soak and flush also works there, and I'll even drive the car for a couple of hours around doing chores or grocery shopping with the vinegar water mix in it.
My favorite method for flushing a block in the car is to use a water hose and compressed air both at the same time. (and the more air pressure the better on the block flush)
The blast of air along with the water causes a high speed blast of air/water mix to blow through the block WAY faster than the coolant ever travels, and doing it through the stat opening is forcing it backwards of the normal flow so it really carries the junk out.
Put both in your thermostat opening without the stat, wrap a wet towel around the hose and air chuck both and hold it there tight.
Let about 5 seconds of water go in and then hit the air until mostly air comes out the bottom hose outlet of the water pump.
I repeat this about 5-6 times or until I get clear water coming out with each blast.
It works well on radiators as well, but you have to be a little conservative about how much air pressure you use as to not split a cooling tube.
Same with backflushing the heater core since they all share the same cruddy coolant.

yep, some good stuff from you guys. i actually have a chem pump that will be used to flush the block in conjunction with air.
 
in the video, looked like the shroud wasn`t tite against the rad. , the fans blade should have only about 1/2" clearance, unless ur engine moves around a lot. I like 1/4" to 3/8', but my engine doesn't move around at all-----------
Will be testing a thermostat like yr suggested a while back next.


its not tight, thats one of the few fixs i got to do. i got a torque strap so it dont go to far. 1/4" is a bit to close for my liking. kind of limited to shroud diameter and available fan diameters. as i said i think the next size from 18.5" is 20" and thats going to be to tight. unless there is another fan blade size im missing?
 
its not tight, thats one of the few fixs i got to do. i got a torque strap so it dont go to far. 1/4" is a bit to close for my liking. kind of limited to shroud diameter and available fan diameters. as i said i think the next size from 18.5" is 20" and thats going to be to tight. unless there is another fan blade size im missing?

Not doubting ur word, but ur having more trouble than I do, and I can only run a 17" mechanical fan. I`m still experimenting tho. If I ran a larger fan, it would hang out the top and bottom more, and maybe the pass. side too.
I`m currently having a 1" ring heli-arced on the shroud to almost cover the fan to the rear.
Will be interesting/I`m going to drive it to mens prayer breakfast this morning w/ no shroud, bet it cools real well on the hiway.
 
Not doubting ur word, but ur having more trouble than I do, and I can only run a 17" mechanical fan. I`m still experimenting tho. If I ran a larger fan, it would hang out the top and bottom more, and maybe the pass. side too.
I`m currently having a 1" ring heli-arced on the shroud to almost cover the fan to the rear.
Will be interesting/I`m going to drive it to mens prayer breakfast this morning w/ no shroud, bet it cools real well on the hiway.
440 with a 17"fan and stock 3 core style radiator, is that what you have?
 
2. fluid looks cruddy, guessing from the dyno pulls it got some junk stirred up. brown rust color. was green before tune.
ok, i have to ask. if this is a new build, WHY is there "junk" in the coolant if this is a fresh build? old radiator? did anyone remove all the freeze plugs and clean the coolant passages? old heater core? :realcrazy:
 
I have to go with MOPAROFFICIAL on fan in the shroud, The only way the air can come back out the rad is if you have to much fan is in the shroud. The air coming off the end of the blades has no where to go because the shroud is in the way, It's hard to tell from the vid is there a spacer between the fan and pump if so pull it out and trim the shroud to fit tighter against the rad fill the gaps and see what happens
 
ok, i have to ask. if this is a new build, WHY is there "junk" in the coolant if this is a fresh build? old radiator? did anyone remove all the freeze plugs and clean the coolant passages? old heater core? :realcrazy:

that i do not know? car was bought with everything already done by someone else. i did not over see any of the rebuild process. so today was a discovery/tear down and see what we got. this is the crap that came out of the radiator
IMG_2538.jpg
IMG_2539.jpg
 
I have to go with MOPAROFFICIAL on fan in the shroud, The only way the air can come back out the rad is if you have to much fan is in the shroud. The air coming off the end of the blades has no where to go because the shroud is in the way, It's hard to tell from the vid is there a spacer between the fan and pump if so pull it out and trim the shroud to fit tighter against the rad fill the gaps and see what happens

no spacer, and thats the short version of the fan clutch. im gonna fool with it and if i have to loose the clutch to get the depth right thats what ill do and just go with a fan only set up.
 
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