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OK, I know the main tank has a regular radiator cap on it.

The expansion tank on my car is old and crusty and dropping bits of rubber and shit into my cooling system. I've lined it with plastic to seal it temporarily, but I want to install the proper cap, or repair my existing cap.

My question is, Is the expansion cap a sealed cap? Or is it designed to let air in and out to acommodate the raising and lowering levels of coolant?

I was told to just use a regular radiator cap without the guts, but that leaves a small hole in the top. To me that sounds fine, the tank is just there to accept and give back the coolant that expands and contracts from heat as the engine goes through it's heat cycles.

I thought though I read somewhere that the Pantera cooling system was a closed, sealed system. In that case, the expansion tank cap should make a good seal and not let air in or out,.

So which is it?

I bought a radiator cap that I can cut the spring and lower plunger seal off of, but that leaves a small hole in the top.


I also bought some rubber "gasket maker" that I can cut a circle or 2 to fit the old cap and have it sealed (as it was before I believe.

Thanks for any help.
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first, given coolant mods are fairly common, but their implimentation vary grately,
does your expansion tank ONLY have the over flow hose from the supply tank into its bottom, with a drain off hose at the cap neck.

I have my "opinions" of how the coolant system "could" work, but I am new to the group so mine should be over ridden by those with more knowledge.

I invisioned the original designed expansion tank as an overflow reserve, thus the cap does not need to have a lower pressure seal and the cap mainly serves as a dust cover and top sealing used.

CORRECTION TO ORIGINAL REPLy

would it hurt if the expansion tank had a lower seal and a pressure setting...maybe. by having a pressure in the expansion tank it would increase the relief of the supply tank.

SORRY for the original erronoius posting

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In my stock system, the expansion tank wasn't pressurized, and the cooling system blew and sucked through the radiator cap which was mounted on the swirl tank.

The cap I had on my original expansion tank just had a flat gasket. The cap had no springs, or any of the other "accoutrements" that a pressurized cap would have.

Carroll Smith only suggests one configuration in "Race to Win"... This is the same diagram George posts in his cooling system sticky.

Wouldn't having a lower pressure cap on the expansion tank effectively lower the pressure on the whole system (if you modify the system per the drawing below).....

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Mike,

Assuming the cooling system is unmodified in terms of how it operates, assuming there's no "gotchas" to bite me on the arse, the expansion tank cap should NOT be sealed tight, it should be vented to atmosphere. Therefore the expansion tank actually operates as a simple recovery tank.

To be technically correct an expansion tank is a recovery tank that operates under pressure. Ford/De Tomaso literature refers to the tank as an expansion tank incorrectly.

Of course the whole concept of a coolant recovery tank was fairly new to the US auto industry in 1971. When Ford began equipping production cars with recovery tanks they were made of plastic and none of them had a pressure cap. Expansion tanks were European contrivances in that time frame.

The concept of a swirl tank paired with a header tank was foreign to everyone at Ford except those who had worked in the Indianapolis or GT40 racing projects. I have been fairly vocal about the fact that I suspect those two tanks were originally configured as a swirl tank and header tank. Whether or not that is true is a moot point in terms of functionality. If anybody wants the cooling system to automatically remove air from the radiator and isolate that air from the cooling system, that is how the system MUST be reconfigured. It is very easy to do.
Looking at my car, I'm not sure if the cooling layout change has been made or not.


The cap for the expansion tank had just a rubber seal, so it's sealed as I bought it and as it is running now.


The main tank is 100% full, and the expansion tank runs at 50% full. It all seems to work perfectly, even in traffic 150-180-150-180-etc.

I bought some rubber gasket material and plan to just put it back the way it was.

It WAS sealing, but the rubber was seriously degrading and decaying and falling apart into the cooling system.

I lined the cap with plastic to prevent any more crap from falling into the system, but the plan now is is to put a new rubber seal back on the old cap and run the car as it's been running, as it seems to be operating perfectly.

I am more used to the newer car setups that have an expansion tank with a small vent hole, that allows the coolant level to rise and fall without pressure changes to the expansion tank (unsealed) but since mine seems to be working well as a sealed setup, I'll just leave it alone for now.
You just need an old fashioned non-pressurized radiator cap for the "catch" can.

The "expansion" or "swirl tank" takes a 15 or 16 psi cap (I use a 16 but that is the safe limit of the old radiator with 50/50 anti-freeze). That gives me about a 245 degree safe limit and therefore makes 220-230 not a problem. In fact, that has a lot of benefits to it.

The expansion tank gets filled to the top. The catch can gets filled 1/2 way. It should also have an overflow hose on it. Run that down under the car so that if it does overflow at some point it doesn't spill anit-freeze all over the engine.

You should keep it as far away from the tire as you can too. Anti-freeze is slippery and that tire would spin if you overflowed while driving the car.

A couple of the Panteras that I have seen were running constantly with a couple of inches down from the top on the "expansion" tank.

It caused no problem for them. That does make sense because one of the reasons that tank is in the system is to provide a place for trapped air in the system to accumulate and not cause problems.

Some cars seem to do that more than others.

Mine doesn't but maybe that's because I was able to get most of the air out of the system and others weren't? I don't know the answer to that other than it doesn't seem to be a problem.

I do know more than a few aluminum radiators had to be replaced at about three years old due to holing through AND cracks in the tubes.

Once that happens with an aluminum radiator it's worth $.23 a pound in junk, because that's all it is.

Get a nice thick core brass radiator when you replace the aluminum. Those are repairable almost indefinitely.

The ONLY value of an aluminum radiator in a Pantera is to lower the cars weight. It DOES NOT cool better than the brass does. Anyone who tells you it does is shoveling horse manure. If you believe them then what does that make you? If you don't mind putting in a new $600 aluminum radiator every three years or so, then get what makes you happy.

The only thing is the aluminum have the damnedest tendency of "going" at the worst time and the worst place you can find. I'd rather be somewhat in control of that and at least I can get any radiator shop, anywhere to solder up the brass.
My car has the Fluidyne radiator, it MAY have a minute pinhole leak, but I'm not sure.

When I get gas at the station where the ground is uneven, I get a tiny puddle of coolant that drips from the right front.

When I check my fluid levels, they don't change.

When I look under the car, it doesn't drip, everything is dry, doesn't leave any drips on the garage floor, so I'm not sure if I have a leak or not.

I think there might be a channel where the coolant gets trapped, or collects, maybe from THE tiniest leak, or maybe from when we bled the coolant system recently.

In any case, presently, it's not leaking badly enough for me to do anything about it.

When the radiator finally blows, or starts leaking badly, I'm not sure what I'll replace it with.

Isn't there something that can be done to neutralize the electrolisis, so I can keep running my cool looking jumbo aluminum radiator? They sure do look a lot better.

If it comes down to having to spend a grand every 2-3 years on a radiator though, well, then brass it will be.

I don't spend any time looking at my radiator anyways lol.
quote:
Originally posted by mike the snake:
My car has the Fluidyne radiator, it MAY have a minute pinhole leak, but I'm not sure.

When I get gas at the station where the ground is uneven, I get a tiny puddle of coolant that drips from the right front.

When I check my fluid levels, they don't change.

When I look under the car, it doesn't drip, everything is dry, doesn't leave any drips on the garage floor, so I'm not sure if I have a leak or not.

I think there might be a channel where the coolant gets trapped, or collects, maybe from THE tiniest leak, or maybe from when we bled the coolant system recently.

In any case, presently, it's not leaking badly enough for me to do anything about it.

When the radiator finally blows, or starts leaking badly, I'm not sure what I'll replace it with.

Isn't there something that can be done to neutralize the electrolisis, so I can keep running my cool looking jumbo aluminum radiator? They sure do look a lot better.

If it comes down to having to spend a grand every 2-3 years on a radiator though, well, then brass it will be.

I don't spend any time looking at my radiator anyways lol.


I agree, they are pretty.

Google sacrificial anode. It will give you some ideas on how to do it.

I've seen some very nasty corrosion on aluminum intakes but in the Cleveland you don't need to worry about it because there is no coolant in it.

The water pump is pretty hefty but the radiator is rather fragile in regards to corrosion.
"When I get gas at the station where the ground is uneven, I get a tiny puddle of coolant that drips from the right front."

The area the coolant is collecting is in the valence/front crossmember area, also known as a great sand and debris catcher that is difficult to clean and very prone to rust. A tough area to repair after the fact.
quote:
Originally posted by larryw:
"When I get gas at the station where the ground is uneven, I get a tiny puddle of coolant that drips from the right front."

The area the coolant is collecting is in the valence/front crossmember area, also known as a great sand and debris catcher that is difficult to clean and very prone to rust. A tough area to repair after the fact.


Yup! I think you have an issue on the bottom of one of the tanks.

Not only do the aluminum radiators hole through, unfortunately, the aluminum itself develops cracks longitudenally in the tubes.

They just appear out of nowhere and will continue to grow.

The aluminum just does not have the same duty cycle longevity as brass does.

Ironically I was just speaking to a friend and asked him about his three year old aluminum radiator in his Pantera.

He was like all these other guys who act like the aluminum is the best discovery since electricity.

You had to hear him curse out the aluminum radiator. The thing just virtually disintegrated literally overnight.

All the seams started leaking, cracks in all of the tubes, etc.

He has the original brass radiator back in there and just doesn't want to talk about this subject any more. LMAO!

Everybody thinks I make all of this stuff up? Roll Eyes
Yeah, but they look SO cool! lol

When the time comes, I'll probably put a brass one in, as long as the install doesn't take a bunch of fab work.

I'm new to these cars, so I don't know if the Fluidyne was designed to just drop in or whether custom mounting was required.

At the auto parts store, I saw one of those caps with the anode, dangling on a spring, I think I'll install one of those too.
The Fluidyne is an exact replacement radiator.
If you don't have the original Detomaso radiator (maybe Roger still has it?) I'd recommend buying Hall's replacement brass one.

It has an extra thick core.

Gary called them the Phoenix radiators because that's where he supposedly tested them in the heat of the summer.
The "girls" don't know anything about that reference now so don't even bother to ask them about it. The one they sell IS the "Phoenix".

Look out for that dangling anode. It will begin to dissolve as a result of galvanic action and if it isn't made with a securing wire core, then it could drop chunks into the system as it dissolves.

Check the manufacturers information on it before you put it in and forget about it?

http://www.summitracing.com/pa...se3eFto8yhoCK7zw_wcB
quote:
If you don't have the original Detomaso radiator (maybe Roger still has it?)

I have my original radiator if you'd like it. At minimum, it probably needs to go to a local radiator shop to be rodded out and have the tanks re-soldered. At the worst, it might need a new core; a competent radiator shop could tell you. I had the same symptoms you describe, so I installed a new copper/brass radiator from PPC Reno (Larry Stock) about 7 years ago. I was going to rebuild my radiator, but Larry had them in stock and I was trying to get my car back together in time for Concorso.

Anyway, I still have the original and you can have it if you want.

FWIW, the Phoenix radiator from Hall is an extra large extra capacity radiator, not a stock replacement.

As far as cooling capacity, I've never had any cooling issues with my stock style radiator, including sitting in 100 degree weather in stop and go traffic on Hwy 17 going over the hill to Santa Cruz.
Garth I might take you up on that offer for that radiator.

I do know I want to have bulletproof cooling on my car.

So far, I have 4 or 5 hours driving in my car, 2 or 3 of which are after fixing the car.

So far, it is running sweet. My gauges are all telling me the right info, no leaks (at least nothing is dripping from under the car after drives)and it seems to just run perfect, so I'm happy again.

I don't trust the radiator in the car though, and I expect to have an issue with it sometime in the future.

I think it has a Teeeeeny pinhole leak, that's causing that little bit to collect in the front of the car and leaks when I go to that particular gas station.

I expect that to get worse over time, to the point where I'll be needing to replace the radiator, but I want a jumbo, beefo, ultra radiator that can handle long periods of traffic, the way it can now.

Presently, I can sit in traffic for hours and watch the gauge go 150-180-150-180 all day.

I want to keep it running that way.

When the time comes to replace my radiator, whether it be aluminum or brass, I just know I need it to perform.
Once you get into the US L version of the car, it has the details worked out.

All that ANYONE NEEDS is a stock L brass radiator. As Garth pointed out, they handle hot desert conditions in traffic with the A/C on with NO PROBLEMS.

Lots of these issues that you hear of with Panteras are PRE L issues and there seems to be some type of mass hysteria with the people who buy these cars.

The Funkle brothers, Simon & Gar, once wrote, "the words of the prophets are written on the subway walls, and tenement halls". I think that's where some people get their Pantera information from?
quote:
Originally posted by mike the snake:
I have read about the pre-L models having overheating issues in traffic early on.

I'm not buying into any hype, I just want my car to run without issues.


The setup is so good on the L's that you start to reintroduce issues as you modify the cars.

There is a quicksand type of thing going on with some people. People walk right into it, then the more they struggle, they just make their own problems that never existed before?

Leno's comments on his blue Pantera is a good example. He knows a little bit about them, but not enough and he feeds into the paranoia.
Doug,

I spend a lot of time researching about these cars, so I read everything, good and bad, true and false.

That's why I'm asking here, because somewhere, between the answers, always lies the truth.

I'm just a few hours into owning/driving my Pantera, so I'm learning, finally getting to drive and enjoy my car.

Forgive me if i ask redundant questions, even if I come off looking ignorant, I'd rather ask and know.

I appreciate your amswers. You always give the straight skinny when it comes to answers.
quote:
Originally posted by mike the snake:
Doug,

I spend a lot of time researching about these cars, so I read everything, good and bad, true and false.

That's why I'm asking here, because somewhere, between the answers, always lies the truth.

I'm just a few hours into owning/driving my Pantera, so I'm learning, finally getting to drive and enjoy my car.

Forgive me if i ask redundant questions, even if I come off looking ignorant, I'd rather ask and know.

I appreciate your amswers. You always give the straight skinny when it comes to answers.


I have NO issues with the way you proceded at all. You try to do your homework BUT there is this prevailing attitude that exists in regards to the Pantera in general.

It totally reflects negatively on the car as a whole and is constantly fed by the false information stated by the "Chicken Littles...the sky is falling" crap.

I do the best I can to counteract it in behalf of a very little appreciated Marque but it just gets overwhelming at times.

I do like the quote "it takes 4,650 nuts and bolts to put a car together and just one nut behind the wheel to destroy it."

It sounds like you are getting to an understanding of your car which is going to help you enjoy it with little problem for years to come? Plus you are getting to a point like with an M15, that you can field strip it blindfolded in the dark and reassemble it in 60 seconds. That helps alot in the field.

Don't forget you need to put a condom over the barrel to keep the rain from seeping in rusting and jamming the action. In the jungle, that happens overnight. Big Grin

I hope that is the case and you will come to realize that I portray things as accurately as I can, attempt to explain and try to state it "like it is" and there are those that flat out, "don't like that"? Rains all over their parades I suppose?

Best and enjoy. You're gonna' be ok with this. Big Grin
I have thick enough internet skin to deal with most responses, and I appreciate your frankness in your answers.

You are correct in that I am getting to learn my car.

Chuck and Ron helped me with the things I literally couldn't do, because I was injured, and either didn't have the tools, or the knowledge, and then they left me to finish the rest myself, which I did.

They really saved me, but now it's up to me to keep up and maintain my car. Nobody's going to hold my hand through all this.

In doing so, I learned a LOT about my car, and it's innards, and that it's a total bit$h to work on, no matter what you might be doing! lol.

BUT, now I have my car back running, and running well I might say.

I know there's way more room for improvement and fine tuning to do, but I think I might have to upgrade my ECU so it can be tuned by today's standards and equipment.
On the ECU you will get varying opinions. I think though that there is little to be gained in changing it although adding more sensory input makes the comprehensiveness more accurate to responding to varying conditions.

I think though that if you have good power now, good idle quality, easy starting and no issues with pump gas then it is fine and leave the current one alone.

Basically all you would be doing is adding ignition control to the ECU.
You don't need it. The old stone (stoned) age mechanical curve in the distributor is doing just fine.

Why open a new can of worms needlessly. Drive the car and try to get a feel for the need for improvement or not. Sometimes those things are two steps forward and one back and you would need to change the distributor again.
That is my plan. Unless I have an issue, the plan is to drive and enjoy the car.

My next things on my checklist are adjust the valves, detail the interior, finish dialing in the rear decklid mounting, give the paint job a good buffing, fix all the new scratches that happened from all the work we did, and just drive and enjoy the car.

I do have a question though. IF the timing were too advanced (which I do NOT think it is) can that cause pinging at around 3000rpm under no load?

I keep hearing tiny little ping or tink noises when I'm going up through the gears easily, under basically no load, and was wondering if this could acutally be pinging, or of it was more to do with the injection (which I think it is). Throttle is basically feathered and rpms rising lightly as I go up through the gears, and I hear these tiny tink sounds when a car is next to me (reflecting the sounds back at me).

The timing seems pretty dead on, it starts perfectly, idles down perfectly, so my thoughts are it's just the injection doing it's thing and I'm just learning about the noises my car makes.

Again, the car runs sweet, so I'm not all eager to run off and play with the timing, I was just wondering if the engine can ping under no load?
Yes it could be but a slight ping under no load, you just leave it alone. It just means that the ignition advance is maxed out.
That's determined by the characteristics of the fuel and how much of a combination of ignition advance and static compression the fuel will take. It's the fuel that determines that more than anything else.

Your camshaft timing probably has more duration on the exhaust than the intake. There is a calculator that the cam makers use where they determine the timed compression ratio or the "effective compression ratio". Theoretically they blow some static compression out of the exhausts.

The problem is that the ACTUAL octane rating on pump gas varies just enough to make that cam timing trick on the street not even worthwhile.

People say you can run the compression ratio higher with aluminum heads and fool the fuel octane.

In my experience, neither of those work at all. The ONLY consideration on this is the static compression ratio of the engine, the compressability of the fuel (the actual octane not the posted,i.e., resistance to detonation) and the ignition advance.

Ignition advance raises cylinder pressure like you are raising compression ratio.

The ONLY way you could fix that IF you deemed it needing to be fixed would be to change the CPU to one that controls the ignition completely and change the distributor to one that is compatible with that theory or process. Then completely re-write the advance program in the CPU.

You probably would need to install a knock sensor for the NEW CPU?



IF you have the vacuum can hooked up to the engine now, assuming that you have a vacuum advance on the distributor, it is that vacuum advance that is creating that slight ping probably.

At light load the vacuum advance is maxed out usually.

It is also tune able. There is an Allen set screw inside of the vacuum nipple that can be set to slightly reduce the total vacuum advance that is providing.

Usually for "high performance" useage vacuum advance mechanisms are removed and that part of the advance mechanism internally in the distributor is locked out.

Reason for that being is somewhere over 6,000 rpm that mechanism becomes unstable and bounces making the advance timing unstable and therefore that part of the rpm curve un-tuneable.



I would leave the entire thing alone at this point UNLESS when you WOT you feel the car loose power like it wants to stall. If it does that, you have detonation and maybe very serious untimed spark?

If it does that, get out your timing light and take a couple of degrees out of the static idle timing and try that again until it stops doing it.



Lots of engines like yours are being limited to somewhere between 32 and 34 degrees total advance. I wouldn't expect any Cleveland with a closed chamber head to be able to run 36 on pump gas. Even if it was able to, it may loose power there so what would be the point?
Once again Doug, thanks for your insightful reply. I've learned a LOT from your posts alone.

I replaced the distributor with an identical replacement from what was on the car before, which is mechanical advance only. No vacum advance.

It's a Unilite disstributor. Many have told me I should have replaced it with something better, but It ran great before, so I replaced it with what it had before, just to limit variables.

As I expected, it runs exactly like it did when I test drove it and bought it, so I'm happy at present with the way it's running.

Again, I'm sure there's fine tuning that can take place, with someone who knows what they're doing, but it runs great right now, so I'm just going to drive it and enjoy it.
Engines like yours (and mine too) make so much freakin' noise that sometimes it's tough to find where they are coming from.

It is so far from stock that it is tough to identify the new sounds it is making.

I currently have, one, two, three...I had to stop and count them, that are all making strange, i.e., no stock noises. Wait...four.

One is my sons Contour with a supercharger on it.

To the novice, "there is something wrong with your engine" sounds?

Just those comments makes me stop and check them but largely the issue is that there is so many "old school" high-performance/racing components in them that the general public never got that close to them before and never listened for this stuff?

Even the "old school" Ford power steering pump in my Shelby has been silenced by changing the fluid to a different type (Lucas stop leak) so now people who have other Shelbys say "what's wrong with your ps pump, it's too quiet, is it disconnected?" because it's TOO QUIET NOW!

It never stops Mike. When I was in Texas there was an expression, "real Texans wear 10 gallon hats because when the s.it comes down, 5 gallons isn't enough".

I had a local cop "deem my Pantera engine compartment" TOTALLY ILLEGAL. The thing wasn't even running. Just the decklid was open and he saw the engine.

Poor moth fettered too close to the flame?

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Last edited by panteradoug
Pre-L Panteras overheating? That story goes back to 1971 when the first gen radiators had coolant tank baffles that negated cooling from about half the core. Redesigned from a vertical baffle to horizontal baffle in '72; problem fixed. Remaining "overheat problem" comes from a water temp gauge that reads wrong AND has too small a gauge span. V-8 cars built in the late 20th century run 210-240F ALL THE TIME. The early Pantera gauge shows 0-220F: result was panic in unknowing drivers when the needle swung way-right. Fix for that mental issue was the '73 gauge that has a 0-250F span and maybe a more correct calibration with the U.S sender.

On aluminum rads: virtually everyone talks endlessly about heat transfer coefficients and theory without addressing the real issues. That is, water flow thru the assembly. Brass rads use maximum 3/4" wide x 1/8" tall x 0.040" wall transfer tubes inside. Aluminum rads use 1", 1.25" or sometimes even wider x 040" tall x 0.050" thick wall transfer tubes. Result is, the aluminum rad flows 2x to 3x more water at the same internal pressures. Any brass rad is a flow restrictor! Thinner or larger brass tubes cannot structurally support stock water pressures- and rad makers have tried endlessly.

Second, in some areas of the country the local water is SO corrosive, it will dissolve a piece of scrap aluminum in a tumbler overnight. The fix here is No-Rosion additive or something similar. Corvettes & Z-28s have had alum rads since 1980 and the specialty shops have a test they run using a GOOD VOM. Remove the cap and drop a lead into the coolant & ground the other lead, with the meter set on minimum amps. If the meter reads above 50 milliamps of electrochemical current, the chemical action inside your cooling system is very busy dissolving metal. My coolant system reads 18 milliamps with local water, 50% Prestone and no sacrificial anodes. I still change it yearly. My 13 yr old aluminum rad, 25 yr old aluminum heads and aluminum waterpump all show no corrosion inside. Note this current reading occurs with the key off and zero power to the car; the car battery can even be removed.

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