Air bleed holes in heads

Hey Larry,
I have been following Asa’s thread on the “other“forum. I can not see the point of drilling the heads when it seems that 99% of the cars can be properly bleed without tempting the Italian mistress of fate. It would seem that Asa’s problems are more than an improper bleed and most likely the thermostat. I thought he posted something about putting in some kind of restrictor plate to be able to use a standard non Cleveland thermostat. Maybe that is his problem.

Are you having cooling problems?
Jeff

I don’t understand the problems people have bleeding air out of the system. I might be just lucky but it has never been a problem on my car.

Mike

Same here ... I have never had an issue getting the air out of my system. As a matter of fact I kind of relate it to a standard hydronic heatings system with as long as you have circulation eventually all the air comes out ... leaving the radiator cap off for a few minutes allows the air to escape. Only place possibly a little bleeder will help is the top of the radiator and factory my car has a little rubber hose that allows that to escape. But once circulation starts like a heatings system the air will work its way out fast .. air pockets ..I dont see it the tanks are at the high point.

Ron

quote:

Are you having cooling problems?

My only problem is higher temps than 30,000 miles and seven years ago. I used to run about 180 on a HOT day at highway speeds. Returning from Monterey on a HOT day I was running around 210-220. No,I did not boil over, but I know the car can run much cooler, and I want to return to those cooler temps.

I had to use some Bar's Leek three years back. My aluminum triple pass started seeping. No more leaking, but I feel it has started grabbing trash and clogging things up. It has epoxied tubes in the tanks, and can't be worked on. I could boil it out and regain the flow, but also the leak.

Air bleed holes keep coming up in discussions. It just seems that they surely can't hurt, and this would seem to be the time for me to install them.

However, my personal experience echoes others in that I have never had a problem getting air trapped in the system.

Larry - not following the KISS protocol

About 12 years ago I purchased a new brass/copper radiator from Hall. It is thicker than the OEM and seems to do a good job in cooling. It has been repaired twice for minor leaks. Annoying but better than having to replace the aluminum radiators.

Dick Koch is actually still running his original OEM radiator in his twin turbo. The only up grade I am aware of is Meriah fans. He says he never has cooling issues.

quote:

About 12 years ago I purchased a new brass/copper radiator from Hall.

Good point. And I guess since I am having
Ron Davis build a new triple-pass,I could ask him about doing it in copper/brass.

But the current one was installed about 35K miles ago, around 1995. So really, replacing every fifteen years isn't really that bad.

Larry

quote:

I don’t understand the problems people have bleeding air out of the system. I might be just lucky but it has never been a problem on my car.

Same here.

Larry,

What temp gauge are you using and have you checked it lately for accuracy?

quote:

I have never had an issue getting the air out of my system.

Ron,

I've never had that issue either, car included.

John

quote:

What temp gauge are you using and have you checked it lately for accuracy?

Mechanical VDO.

And no, perhaps I should get the infrared temp gun out before I go throwing money away.

Thanks for the idea.

Larry

Larry

where are you plumbing those air bleeds to?

If you're copying JT, he has a surge tank (i.e. a true low pressure tank designed to collect air) in his Pantera. So his air bleeds actually work. The Pantera swirl tank as it came from Modena is an ineffective place to plumb air bleeds. Although I'll admit the heads should vent to the swirl tank OK.

Once you initially burp the air from the cooling system (raise the rear, then raise the front) air shouldn't collect in the motor, air will form at the pressure drops downstream of the thermostat and downstream of the radiator. That's where the bleeds need to be, but you need a true surge tank like JT's to dump the air into.

the way to cool a Pantera is a good radiator & lots of coolant flow. If your temps are truly creeping upward, perhaps the radiator is accumulating scale on the inside of the tubes, or perhaps the coolant/water mixture is getting old.

-G

.....for sure its the BARS STOP LEAK ...that stuff will clog up HOLES ... and make sure you flush the entire system and replace the antifreeze with new ... I used it a few times on our service vans and it always clogs up the Heater Core.

Ron

quote:

where are you plumbing those air bleeds to?

My air bleeds would have petcocks only for initial bleeding after refilling. I have not seen a problem, thus I see no need for constant (plumbed with hoses) air bleeding from the heads. If periodic bleeding from those petcocks keeps showing trapped air, obviously my thinking will need some re-evaluating. 2511 is fitted with the air bleed off the top of the radiator back to the overflow tank. Many have said this does not work. Work or not, air isn't a problem in 2511, and my system has, up until recently, worked in an exemplary manner.

quote:

air will form

George, I know you have given the whole cooling system issue more thought than I have, but I don't buy into the idea that air magically forms in a system that has been properly purged of air. (I am open to reading material that will change that feeling; please provide a link if available). While there may well be minor pressure drop areas in the system, I can see no manner in which air will magically form due to such a drop.

quote:

for sure its the BARS STOP LEAK

Ron, I totally agree with you.

Guys, please bear in mind 2511 used to run so damn cool I often wished for more temp during the cool winter month drives. It would idle at 198 on a 100 degree day. Quella wants to sell me a new double pass (and all the new hoses, etc for installing that different style) and new sucker fans (the Meriah fans work just fine, thank you). Following all the JT and George advice would incur running new air bleed hoses, remote stats and rerouting of coolant flow.

I have the Tefba coolant filter at work trapping any crap flowing in the system. It gathered some fine particles and some black silicone pieces during the Monterey trip.

I intend to add some cooling system flush solution and see what that breaks loose for the Tefba to collect.

Once I am satisfied I have purged the cooling system of potential crap that will clog-up the new radiator, the R&R will occur.

I'll check the Gates green stripe and replace if needed (probably not), fill with all new coolant, check new system for any electrolysis issues (install zinc anode if needed) and bleed as needed.

Thanks for all the thought and advice, guys, but I am not looking to reinvent the wheel here - my initial wheel worked just fine. A return to the days of yesterday, with a new triple-pass Ron Davis radiator, should do just that.

Larry

Please elaborate on the Ron Davis radiator ... I'm in the market for a new one for 6476.

Ron

quote:

Please elaborate on the Ron Davis radiator ... I'm in the market for a new one for 6476.

Quella has used Davis Radiator to make his aluminum units for many years. Dennis' current double pass, stock replacement is a Davis unit. As is my circa 1994 triple pass from Dennis.

Sadly, for me, Davis can not make my radiator without their shop drawings and being such an old product, they have been unable to locate those drawings. If I could provide the part number, which they engrave on all their products, we would be fine. But Dennis ground off the engraving to ensure no one could deal direct with Davis. So this Winter, I'll pull mine and ship it to them for some reverse-engineering.

Being a current product, you 'might' be able to bypass Quella and deal directly with Davis to get one of his current double pass OEM replacements.

And I'm sure if you have your own ideas as to what you want, given that they do make units that fit Panteras, I suppose they could do a custom one-off that would drop right in.

Davis is one of THE names in the radiator business. Doubt you could go wrong with anything they produce.

You could call them at 623-877-5000. I've been talking with Bill Williamson on Ext. #16.

Larry

Larry,

Have you checked to make sure that your radiator fans are all working and up to speed? Just another thought.

John

quote:

Have you checked to make sure that your radiator fans are all working and up to speed?

Yup.

The real tell that told me it was the radiator was the drive back from Monterey, when things weren't even right at highway speeds.

My stat is a high-flow, less than a year old.

Bars Leak and 15 years - it is just time. Sigh.

Larry

Larry, refresh my memory- is this a copper/brass radiator?
If so, note that Nor-Cal's Marcus Smith had an unexplained problem with his stock, twice-rebuilt radiator that suddenly started giving him overheating. Only when Marcus absently ran his finger across the core and noticed a fine gray cloud fly out did the problem surface; the solder holding the fins to the tubes had deteriorated and that 'cloud' was lead oxide! Such damage is unrepairable; he installed a new rad and has had zero problems since. I added a Fluidyne aluminum unit some 8 yrs ago (from PIM) and also have had no troubles. The only real difference between Quella's aluminum and a Fluidyne is, Quella uses welded 90 degree hose attachments, while the Fluidyne uses hoses and/or 90 degree fittings. Quella also has a custom dual-sucker-fan aluminum shroud available while the Flexilite dual-sucker-fan shroud I use is black plastic: less bling but the same results on the road.

My Fluidyne with dual sucker fans and shroud from PI works excellent ... even under extreme days at the track ..never even comes close to over heating ... the stock brakes overheating thats another story.

Ron

quote:

Larry, refresh my memory- is this a copper/brass radiator?

Jack,

His 3-pass aluminum, with epoxied tubes, made by Ron Davis circa 1994.

I don't need new fans - Meriahs are fine.

I don't want to reconfigure for his newer stock 2-pass Davis unit.

I'll be pulling it out later this Fall, probably along with the dash. Planning on the 3-speed AC fan blower upgrade and Wilkinson's new evaporator.

Larry