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Cooling issues - and a weird question

Normally I'd agree with you, but in this instance, this has actually motivated me to do what I've been meaning to do for a few years now.
Even with previous, milder, more worn out 440's in the car, cooling has always been an issue. This engine has just exacerbated that situation is all.

On a side note, Professor Ehrenberg is graciously continuing to correspond with me over this and he's recommended the Griffin 2-core aluminum - says no other aftermarket radiator maker is worth the time.
I reckon he means this one:
http://www.griffinrad.com/load_deta...ect_Sub_Group_Transmission=N/A&key_id=5-00004

Wow, what a link. Sorry about that. :)

Oh, and he's clarified his earlier notes on the engine itself - apparently he didn't necessarily think there was a blown head gasket, but that perhaps the builder didn't use the correct head gaskets and they may be restricting flow.
Hopefully, I don't have to find out....
Summit $578 is $50 cheaper than Jegs. Don't know if there's a better price ?
 
Most folks seem to not understand how an engine's cooling system works. The fan does two things. First, it provides direct cooling by blowing air onto the engine, and indirect cooling by pulling cool external air over the cooling coils in the radiator, which cools the coolant. It's all about moving the right amount of air, to the right places, at the right time. Simple as that.

Where guys get into problems is when they modify this system and don't take what it's supposed to be doing into account, and this usually manifests itself in the form of messing up the shroud. The shroud is as important as the fan or radiator as it determines where the fan will get its air and where that air will go. If you don't have the shroud properly placed, it's going to allow the fan to pull hot air from within the engine compartment, which means little or no air is flowing through the radiator and little or no air is blowing on the engine. The air is just swirling around doing nothing but getting progressively hotter as the engine becomes little more than an air heater.

Mounting fans outside the radiator will get air through the radiator, but there's a gazillion angles created by the radiator fins, and these deflect and reflect air in every direction, which creates eddies and currents that push against one another, or in short terms the amount of air needed for direct cooling ain't getting to the engine.

You need a radiator sufficient to cool the engine, a proper-sized fan, and a proper-sized and installed shroud.
 
As in all of it - radiator, fan, clutch, hoses, pump, thermostat and housing. All of it off the car right now.

In fact, while I have the front end wide open, I'm going to pull all the plugs so I can easily spin the motor and do the "verify TDC timing marks" drill on what appears to be the stock balancer. Might as well, perfect time for it and I want to get the timing down pat.

In the meantime, this choosing the ultimate radiator is proving almost overwhelming. So many manufacturers out there, not to mention "4-core this" versus "2-core aluminum with 1.5" tube that" comparisons.
The only thing I know for sure is that I can't afford Glen-Ray; that's just out of the ballpark for me, sadly.
Which way do I go with this?
Remember - overkill.

Further, I assume if I choose a 4-core, I'll have to go with the short Hayden fan clutch, yes?[/Q
Most folks seem to not understand how an engine's cooling system works. The fan does two things. First, it provides direct cooling by blowing air onto the engine, and indirect cooling by pulling cool external air over the cooling coils in the radiator, which cools the coolant. It's all about moving the right amount of air, to the right places, at the right time. Simple as that.

Where guys get into problems is when they modify this system and don't take what it's supposed to be doing into account, and this usually manifests itself in the form of messing up the shroud. The shroud is as important as the fan or radiator as it determines where the fan will get its air and where that air will go. If you don't have the shroud properly placed, it's going to allow the fan to pull hot air from within the engine compartment, which means little or no air is flowing through the radiator and little or no air is blowing on the engine. The air is just swirling around doing nothing but getting progressively hotter as the engine becomes little more than an air heater.

Mounting fans outside the radiator will get air through the radiator, but there's a gazillion angles created by the radiator fins, and these deflect and reflect air in every direction, which creates eddies and currents that push against one another, or in short terms the amount of air needed for direct cooling ain't getting to the engine.

You need a radiator sufficient to cool the engine, a proper-sized fan, and a proper-sized and installed shroud.
Bruz, that all makes good sense to me, but brings up my question. My radiator, fan and clutch are not stock. I think I could benefit from having a shroud , but how do I determine what I should get? I am wondering about fit and attachment............................MO
 
He's a super smart guy, so you're lucky to have his ear. Did he mention which head gasket would do that? I've used most of the aftermarket head gaskets out there but I've never seen one that cause cooling issues.
I'll quote him: "maybe wrong head gasket, blocking passages, small steam slot instead of large hole, motorhome etc.".
Now that he mentions it, I do recall the last few sets of the FelPro "blue" head gaskets having slots instead of full round holes...

In fact, I always wondered:
Could a fella actually open up those holes in the head gasket safely?
 
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Looks exactly like this one from US Radiators for $420. They also have the 3 and 4 core copper radiators. I trust them since I had one of their aluminum radiators before they recored my copper oem one.

Aluminum
http://www.usradiator.com/plymouth-gtx-1966-69-v8-383-426-440-aluminum-radiator-4675.html

More choices
http://www.usradiator.com/radiators/plymouth/gtx.html?cat=1710
Oh yeah, trust me, I been wearing their site out lately. :)
About the only difference I see is the US Radiator unit has 1" tubes versus Griffins' 1.25".
I watched the video on US Radiators' site this morning, in fact. The owner was walking around, giving a tour of their facility and I was very impressed - but I caught one thing he said when they briefly went over aluminum radiators.
He said they bring in their cores for those from outside because the heat required to do aluminum is like 1000F versus what he runs for the brass/copper.

Either way, I wouldn't have a problem with one of their units. Looks like a class act.
 
Bruz, that all makes good sense to me, but brings up my question. My radiator, fan and clutch are not stock. I think I could benefit from having a shroud , but how do I determine what I should get? I am wondering about fit and attachment............................MO
I guess I'm about to find all this out as well.
I do know I'll be putting a new stock shroud on and I do know I want to run the stock 7-blade fan and a clutch and that the blades need to be about half in/half out of the shroud to work correctly.
How close is TOO close for the fan to the radiator, though?
I think I'm about to get in trouble there. I about certainly will be fetching a "fatter" radiator and my clutch now is only about a half inch off the radiator.
 
Of you think its a head gssket you can rent/ buy a pressure tester thst might help you confirm...
From what youve said here sounds like you had a lot of air trapped in the block. But like Bru and others have said a fan without a shroud does not cool properly.... will ot work? Under certain conditions certainly...but as those conditions deteriate and are not so favorable you will see the flaw in the set up...
 
I would LOVE to find one of those springs, did some time searching for one to no avail. I remember watching an episode of Engine Masters and the engine they were dyno-ing would suck the lower hose shut every time they did a pull!

Ed, I'm following your new thread and hope you solve your heating issues. I have had some similar issues with my car which have been mostly solved but one thing I still notice is the temp going up at high speed cruise when it should stay down. I read about the lower hose spring and checked mine today - no spring! I've ordered from CJ Pony, we will see. Good luck.
 
Let the buying frenzy begin!
Started out by thanking Professor Ehrenberg by buying a Mopar fan shroud from him:
http://www.ebay.com/itm/222537532167
Since the demise of Mopar Action, I feel like he needs all the support he can get.
Such a positive force in our hobby! Always been incredibly helpful to folks.

Onwards to Summit. Love me some Summit, always great service....
1. The Griffin radiator:
https://www.summitracing.com/parts/gri-5-00004
"Exact fit". Shroud should bolt right up to it. With what, I guess I'll figure out, because the Griffin doesn't have studs like a factory radiator.
2. High volume water pump, probably the Summit one. 8 fins. Brazed so as not to come apart in there.
3. Goofy part time - how about a Mr Gasket radiator cap with thermometer?
https://www.summitracing.com/parts/mrg-2471s
Maybe that will help settle the score between my factory gauge and the aftermarket one?
4. Throwing in a couple bottles of Water Wetter for good measure....
Will be running 50/50 pre-mix again, straight out of the Prestone jugs and Water Wetter says it's compatible?
5. The Hayden 2947 shorter fan clutch. Since the Griffin says it's 3" thick and my old 3-core was somewhat less (the tanks are 3" though), it's a pretty safe bet I'm going to have fan (actually, clutch) clearance issues with the stock clutch.
Stock clutch measures 3.25" or so; Hayden unit is 2.66". hopefully, that's enough like some of you guys have said. :)
Definitely going to be a stud & nut affair on the clutch mount to the water pump, though. Man, that looks TIGHT in there!

EDIT: Holy crap, my wife is gonna KILL ME....
Pray for me, fellas.
 
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Of you think its a head gssket you can rent/ buy a pressure tester thst might help you confirm...
From what youve said here sounds like you had a lot of air trapped in the block. But like Bru and others have said a fan without a shroud does not cool properly.... will ot work? Under certain conditions certainly...but as those conditions deteriate and are not so favorable you will see the flaw in the set up...
Yeah, it let go a mightly belch when I shut it down last, deep within the engine somewhere.
Good stuff from Bruzilla as always. However, I had a shroud. Not the right one and certainly not all sealed up, but one in the right position and the fan was hitting it about right.
 
Ed, I'm following your new thread and hope you solve your heating issues. I have had some similar issues with my car which have been mostly solved but one thing I still notice is the temp going up at high speed cruise when it should stay down. I read about the lower hose spring and checked mine today - no spring! I've ordered from CJ Pony, we will see. Good luck.
Thanks Don!
Yeah, I've seen videos of these big blocks on dynos making pulls where the lower hose literally collapses under load/RPM.
 
[QUOTE
5. The Hayden 2947 shorter fan clutch. Since the Griffin says it's 3" thick and my old 3-core was somewhat less (the tanks are 3" though), it's a pretty safe bet I'm going to have fan (actually, clutch) clearance issues with the stock clutch.
Stock clutch measures 3.25" or so; Hayden unit is 2.66". hopefully, that's enough like some of you guys have said. :)
Definitely going to be a stud & nut affair on the clutch mount to the water pump, though. Man, that looks TIGHT in there!
[/QUOTE]

I used the 2947 clutch to mount a giant 20" fan and used repro bolts and lock washers. It was a challenge to get them started and only an open end wrench could be used due to clearance. Take a look at my project thread on post #21:
http://www.forbbodiesonly.com/moparforum/threads/txdons-67-gtx-project.116786/page-2#post-910523691

DSCF7257.JPG DSCF7260.JPG DSCF7263.JPG DSCF7265.JPG
 
14969446829951369369039.jpg

Decided to go ahead and pull the water pump today. 8 blade, feels tight and new (other than getting in the way of a rattle can, apparently).

14969448399081667080809.jpg

Inside of housing looks fine also.
I'll wire brush the gasket surface clean.

Now, here IS a slight problem:
14969449596021606915237.jpg

Lower radiator support isn't exactly straight or plumb. Using a makeshift plumb bob, out comes the BFH!
Stay tuned..


EDIT: It just occurred to me how clean that antifreeze looks in the pan below.
It actually did come out of the radiator that way, but I'll still run a strong stream through the engine before installing any of the new stuff.
 
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I used the 2947 clutch to mount a giant 20" fan and used repro bolts and lock washers. It was a challenge to get them started and only an open end wrench could be used due to clearance. Take a look at my project thread on post #21:
http://www.forbbodiesonly.com/moparforum/threads/txdons-67-gtx-project.116786/page-2#post-910523691
That's great, Don, thanks! Yep, looks real tight in there for sure.
I was concerned with my factory 7-blade fitting in the shroud but dang, you fit a 20" in there!
I'm going to be more than happy to use the studs and nuts. They help hang onto the clutch/fan assembly long enough to get the nuts started.
 
This afternoons' progress:
1. Found true TDC and checked the mark on the balancer:
timing marks.jpg
The angle of the photo doesn't show it properly, but the factory mark is dead nuts halfway between my silver "stop" marks using the TDC tool in #1 spark plug hole. This makes me happy.

2. Got the lower radiator support straightened up enough that it now lines up with the upper one much better. BFH wound up not being deployed; instead, a makeshift come-along made of ratchet straps was used and involved the shops' bench leg, in conjunction with a big ol' chunk of wood. Don't ask.
It's a Tennessee thing. You wouldn't understand. :)

3. Spark plug pulled from #1 looks nothing like I expected:
spark plug.jpg

I've only had the car out for three local drives, but dang, that looks too clean (lean?) for my taste. Am I wrong about that?
It's got a big ol' Edelbrock 750 on it, surely it's getting enough gas?
One thing for sure - it isn't running anywhere near rich.

4. Got the water pump housing all cleaned up with the wire brush:
water pump housing.jpg


I reckon I'm all set and awaiting all the goodies to arrive. I just got notified by Summit that the water pump is coming all the way across the country (swell), so I imagine it'll be a few days.
 
size of the carb has no bearing on lean/rich........ you can richen it up with metering rods and/or jets...... the edelbrock booklet has the combos on a nifty little table
 
size of the carb has no bearing on lean/rich........ you can richen it up with metering rods and/or jets...... the edelbrock booklet has the combos on a nifty little table
Of this I am well aware, thanks - I still have the 650 AVS practically new sitting on my shelf from the last engine, along with a full tuning kit from Edelbrock.
Point being, the 750 (Model 1407) is jetted a LOT bigger out of the box than the 650 is, yet the plugs look like this - and she stinks of rich at idle, too.
Interesting.
 
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