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Cooling issues - and a weird question

Put your thermostat into a pot of water, and see with a thermometer whem it opens, and closes. If it's good, drill a couple 1/8inch holes on the flat part of the thermostat to prevent air being trapped. Also, get one of those Harbor freight temp guns. They're $20. Will help you diagnose the problem. Like how accurate is your gauge? Is there a good temp drop from the top of the radiator to the bottom, etc.
 
These guys are firing on all cylinders and what everyone is saying are good things to check. You "might" also have a cooling system plugged in the block/heads. And I HOPE I'm wrong, but you might check for an occasional big bubble in the radiator while running to make sure you didn't blow a head gasket (make the engine really hot). Like these guys have mentioned, lower hose spring, cap, thermostat, fan shroud, radiator/body seals & 50/50 mix (or better yet, water + water-wetter) and maybe give it a really good cooling system flush & check your fan clutch....maybe take a peek at your water pump (inside) to make sure the impellers aren't corroded away. Opening up the radiator core support should also help on the highway.

Now, if you are bound and determined to change the radiator....then your 2-core 1-1/2" tube radiator idea is a very, very good one. Just make sure you have a good fan shroud & seal it along the radiator core support...... and check all these other things too, maybe even remove the thermostat. I've had more than one "brand new" part be bad, so don't assume your new cap/thermostat are OK because they're new.
I've been corresponding with Professor Ehrenberg some today and sadly, he also is guessing blown head gasket as well - or perhaps wrong head gaskets blocking flow.
I sure hope not, of course - and I haven't seen any telltale signs of a blown head gasket yet (white smoke exhaust), but that doesn't mean it can't be.
 
PB is right about softened water. I go to the store and buy distilled water, no minerals.
I had a clutch fan go bad it wasn't pulling air. It was turning but not moving a lot of air. Rev'd the engine and put hand behind the fan hardly a breeze.
Thank you yet again, Fran. Yep, if the consensus is that a clutch fan is the way to go, I will replace this one, no worries. :)
 
Put your thermostat into a pot of water, and see with a thermometer whem it opens, and closes. If it's good, drill a couple 1/8inch holes on the flat part of the thermostat to prevent air being trapped. Also, get one of those Harbor freight temp guns. They're $20. Will help you diagnose the problem. Like how accurate is your gauge? Is there a good temp drop from the top of the radiator to the bottom, etc.
Good advice here, thanks. Yes on the gauges - I have the factory one in the dash as well as an aftermarket "mechanical" one under dash; I had been watching one versus the other and it appears the factory one was actually more accurate, at least at first.

I might have "clocked" the aftermarket one when I re-installed it recently.
I actually did borrow a good temp gun from a mechanic in town earlier last Friday, as I was poking around town. It was difficult to get a good reading on the various surfaces (example - radiator being shiny black threw it off big time).
I finally shot the two sensors for the two gauges - one being on top of the water pump housing (aftermarket gauge) screwed into one of the heater hose outlets.
It read 185 with the car warmed up and idling (highway driving had not occurred yet), yet that gauge said 210, so I knew I had clocked it.

The location of the factory gauge's probe is on the face of the housing, right below the other heater hose outlet. I shot it and got 190, so I figured that gauge reading straight up/in the middle of the gauge was pretty close.
 
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!
I found some that fit perfectly. They are sold on eBay and are for Mustangs. I will check to see if I can find the part # for you.
 
The factory mechanical fan doesn't push, it pulls. That is unless it's installed backwards......
Fan backwards ?? Now that is one I never thought of !. I am going to check that out on mine ! ......................MO
 
I have to say don't use "softener water" since water is "sofetened" with SALT, the same sodium chloride that they throw on the roads.
The salt is used as a solvent and then is thoroughly flushed out. I would doubt that there is enough salt left behind to do any damage. I sure can't taste any. Not to mention that if it where detrimental, I would suspect a lot of eventual damage to pipes and appliances. I still have my original 35 year old water heater and I attribute that to softened water.
That said, I DO use distilled water.
 
I have been told by two radiator repair places, that the black paint they use is special for radiators. Regular paint does not dissipate heat as well as radiator paint. ...........................MO
 
Thanks very much for all the input here so far!

I'm now paranoid that my "new" engine has head/gasket issues, though. How do I tell this with the cooling system off the car? Is it possible to tell, even?
The car wasn't throwing out the typical white smoke before I took it apart - yet, anyways.

Also, in case I haven't quite explained the symptoms clearly (probably didn't) - the car gets plenty warm sitting in the garage, idling - but it doesn't go over the top, losing its' mind !!HOT!! until going down the road at highway speed.
Sort of ***-backwards, eh?
 
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Fan backwards ?? Now that is one I never thought of !. I am going to check that out on mine ! ......................MO
With the engine running at 2000 rpms or so you should be able to put a small piece of newspaper or tissue in front of the radiator and the fan should pull it to the radiator.
 
Thanks very much for all the input here so far!

I'm now paranoid that my "new" engine has head/gasket issues, though. How do I tell this with the cooling system off the car? Is it possible to tell, even?
By "cooling system off the car" I assume you mean the radiator? The best way that I am aware of is to use a block test kit to sample the air in the head space of the radiator (or recovery or surge tank) for the presence of exhaust gasses. I don't think you can do it without the cooling system operating.
 
By "cooling system off the car" I assume you mean the radiator? The best way that I am aware of is to use a block test kit to sample the air in the head space of the radiator (or recovery or surge tank) for the presence of exhaust gasses. I don't think you can do it without the cooling system operating.
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?
 
As much as you don't want to hear it, I cool these high compression, big inch hemis with stock 26" radiator, clutch fan/shroud setups with no issues. If your system won't cool it, there's something wrong. I would be trying lower hose springs long before I'd be yanking it all for expensive aftermarket parts. Diagnose and learn rather than throw money at it.
 
As much as you don't want to hear it, I cool these high compression, big inch hemis with stock 26" radiator, clutch fan/shroud setups with no issues. If your system won't cool it, there's something wrong. I would be trying lower hose springs long before I'd be yanking it all for expensive aftermarket parts. Diagnose and learn rather than throw money at it.
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....
 
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....
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.
 
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