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vegas paul
06-28-2007, 07:08 PM
I'm getting close to reinstalling my recently rebuilt engine (169 ci champion) and I had my radiator out for cleaning/rodding etc. I have a question about the proper radiator cap. I previously had a 4 psi (generic, aftermarket) cap on the radiator, and I noticed my parts manual lists two different ones from the official Studebaker line. There were pressurized and non-pressurized systems, but no distinction (like according to model/trim/serial #) as to which one I should use.

I don't have any kind of overflow tank, just a overflow tube down to the bottom, that drains to the road if overpressurization occurs.

Any ideas, warnings, etc. or does it make any difference?

Las Vegas, NV
'51 Champion Business Coupe G899965 10G-Q4-1434
http://i151.photobucket.com/albums/s144/vegas_paul/1462673_2_350.jpg?t=1180041622 http://i151.photobucket.com/albums/s144/vegas_paul/graciestude.jpg?t=1180041703

Dick Steinkamp
06-28-2007, 07:57 PM
The purpose of a pressurized system is to raise the boiling point of the coolant...doesn't change the temperature of the coolant, only the boiling point.

If you feel the car will generally stay under 212 degrees F (slightly lower at higher elevations), no pressure cap is needed.

A pressure cap will help you find any leaks and/or weak points in the cooling system [:o)], although a 4 pound cap is pretty close to a no pound cap.



http://thenobot.org/images/s2d/s2d_01.jpg

vegas paul
06-28-2007, 08:33 PM
Thanks Dick, I understand completely the theory behind each of them (otherwise I better give my Mechanical Engineer's License back!) however, I wasn't sure if there were certain systems that were originally designed to be pressurized, vs. those that weren't (e.g. based on engine # or overflow configuration). I guess if I pressurize it and find leaks, then I have my answer! The 4 pound cap was on it since I purchased the car, and since I am finally getting around to doing a lot of work on it, I just wanted everything to be right. Strangely enough, I've never had cooling system problems here in Las Vegas, even in summer. With all the additional horsepower (!!) I'll be getting out of my mighty rebuilt 6, I'll have to dissipate a few extra BTUs, so I figured it was a good time to clean out the radiator.

Las Vegas, NV
'51 Champion Business Coupe G899965 10G-Q4-1434
http://i151.photobucket.com/albums/s144/vegas_paul/1462673_2_350.jpg?t=1180041622 http://i151.photobucket.com/albums/s144/vegas_paul/graciestude.jpg?t=1180041703

DEEPNHOCK
06-28-2007, 09:22 PM
One area to be concerned with is the top tank on the radiator.
Most early 'low psi' radiators have top and bottom tanks that do not have 'ribs' built into them to support the tank sides at higher pressures. They can flex and eventually crack.
Take your radiator to a good radiator shop and have him clean it and check it out...at the higher PSI. Ask him to look at the tanks and see how they react. If they are OK, he'll tell you. Besides... That's just good PM.
Remember, there's a difference between a low psi cap, and a high psi cap...
AND there's a difference between a vented, and non vented cap.
A vented cap will allow outside air back in as things cool off and contract. A non vented (closed cooling system with a coolant recovery tank) will only allow coolant back in through the overflow tube, and not allow outside air back in.
Jeff[8D]



quote:Originally posted by vegas paul

I'm getting close to reinstalling my recently rebuilt engine (169 ci champion) and I had my radiator out for cleaning/rodding etc. I have a question about the proper radiator cap. I previously had a 4 psi (generic, aftermarket) cap on the radiator, and I noticed my parts manual lists two different ones from the official Studebaker line. There were pressurized and non-pressurized systems, but no distinction (like according to model/trim/serial #) as to which one I should use.

I don't have any kind of overflow tank, just a overflow tube down to the bottom, that drains to the road if overpressurization occurs.

Any ideas, warnings, etc. or does it make any difference?

Las Vegas, NV
'51 Champion Business Coupe G899965 10G-Q4-1434
http://i151.photobucket.com/albums/s144/vegas_paul/1462673_2_350.jpg?t=1180041622 http://i151.photobucket.com/albums/s144/vegas_paul/graciestude.jpg?t=1180041703

hank63
06-29-2007, 10:47 AM
Radiator repairers often leak test at 2 psi air pressure, with rad under water. Insist on test pressure at whatever system pressure you will run (in your case, 4 psi).
/H

John Kirchhoff
06-29-2007, 03:50 PM
Speaking of coolant draining onto the road, a couple of weekends ago I had something happed that totally surprised me. I stopped at a stop light with my Mercury Topaz, had the ac running, took off and maybe 1/4 mile down the interstate I noticed the temperature guage needle climbing. Shut the ac off and turned the heater on, figured it was a stuck thermostat. That tactic delivered no heat whatsoever and the needle was pointing due north by the time I got it off the road. Ends up the little plastic thing retaining the plastic drain plug in the bottom of the radiator had popped out completely, dumping all the coolant on the road. I bet when that thing came out, it flushed the system in a hurry! To make a long story short, two hours later I was going again. The kid at the local O'Rileys knew exactly what I was talking about since his did the same thing. They carry those plugs as aftermarket parts for less than $4 and both Ford and GM use the same one. I think I'll get a spare and throw in the glove box just to be on the safe side.

cortica37
06-30-2007, 11:03 AM
I, too, missed Studebaker cooling systems in Thermo 101 but my guess is that the pressurized vs non-pressurized distinction is not based on model type but on cars intended to be driven at higher altitudes. At 5000' water boils at about 200 degrees and a low value pressure cap would boost this back up to about 212 degrees. I looked in all my manuals for old Champs and could find nothing addressing this issue. I suspect this may have been a conversion made by dealers or service departments in the affected areas.

Kdancy
01-01-2008, 12:12 PM
I need to get new caps for two different re-cored Stude radiators and was wondering which ones would be recommended. One is a 63 Cruiser and the other is a 55 champion.
Recommendation anyone??

Thanks!

N8N
01-01-2008, 12:34 PM
the 63 should use a 13-14 lb. cap, the '55 may use either a 4 lb. cap or 13-14 lb. cap depending on manufacture date. only one will fit; the necks are different. The earlier 4 lb. radiator tanks will be smooth and "bulgy" while the later high pressure ones will have deep stiffening ribs in them.

nate

--
55 Commander Starlight
http://members.cox.net/njnagel

Dwain G.
01-02-2008, 12:38 AM
Since your '51 has been doing well with the 4 lb. cap, I'd keep it! Pressure ratings of these caps seems to be a well kept secret at Studebaker. I had to rely on aftermarket catalogs to confirm that part # 516009, 4 lb. pressure, is the standard cap for your car.
The non-pressure cap appears to be for use with the optional (and rarely seen) surge tank system.

http://home.comcast.net/~jdwain/images/63.63.jpg
Dwain G.

Mike
01-02-2008, 07:13 AM
I suggest a double sealed 4 pound cap with an after market coolant recovery system.
The low pressure cap will allow the system to purge air out of the radiator and engine. That should make it run cooler.
The recovery tank will also prevent any puddles where you park. Antifreeze is poisonous. Small animals sometimes drink it, because it has a sweet taste.
Mike M.

Neal in NM
01-05-2008, 12:03 PM
Liquids have a specific boiling point, which is the temperature at which a liquid begins to change to a gas. If pressure is applied to a liquid, it must become hotter before it can boil. Pure water in a cooling system (which is not a good idea) at sea level will boil at 212 F. if the system is unpressurized. Water at about one mile up will start to boil at 203 F because atmospheric pressure is less at higher altitudes than at sea level. A cooling system with about 15 pounds of pressure will let the water reach about 250 F before it will boil. At this temperature the water is still able to circulate through the engine, transferring heat from parts that are much hotter than the water without it boiling. As long as the water remains in its liquid form it can transfer heat from the engine to the radiator where it can be dissipated to the atmosphere. Boiling coolant is not efficient at transferring heat and your engine will probably overheat if the coolant is allowed to turn to a gaseous state. Heat transfer can be inhibited by the formation of steam because steam can act as an insulator.

Until the 50's, liquid cooled systems did not operate under pressure, because these cars had much larger radiators with bigger engine compartments under the hood that allowed for more natural heat dissipation than todays cars. With the newer smaller vehicles, with smaller radiator to engine ratios, and emission controls along with the use of unleaded fuels, more efficient cooling systems became mandatory.

The solution for these problems is to operate the cooling system under pressure, isolating it from atmospheric pressure. A pressurized system can handle higher temperatures, with a higher boiling point.

For every pound of pressure increase on the coolant in the system, the boiling point of the coolant is raised by approx. 4 F.

Hope this helps. Neal

Dick Steinkamp
01-05-2008, 12:14 PM
I understand all that, Neal (thanks :)), but I still don't "get it" in real life applications.

I can't imagine any of us running our Studes at 250 degrees F. In fact, my newish GMC Sierra (my only non Stude with an actual temp gauge) runs at a consistent 210 degrees (hot days, cold days, towing, etc.)...and that is HOT compared to where we like to see our Studes run. Even it wouldn't theoretically need a pressurized system since the coolant never gets to the boiling point.

So...what advantage is a pressurized cooling system in a car (like our Studes) that run at 180-200 degrees F?. Raising the boiling point of the coolant with pressure doesn't seem to be a factor for us.

http://i149.photobucket.com/albums/s66/ddstnkmp/54%20starlight/HiResS2Dsig2.jpg

Mark57
01-05-2008, 01:22 PM
My '57, which sports a '63 car 289 motor, runs with a 7 lb. cap and seems very happy whether idling in traffic or cruisin' down the hwy.:)

<h5>Mark
'57 Transtar
3E-6/7-122 </h5>
[img]http://i186.photobucket.com/albums/x153/MarkH57/MrGreenJeans1003b.jpg

Dick Steinkamp
01-05-2008, 01:59 PM
quote:Originally posted by Mark57

[green][size=2][font=Comic Sans MS]My '57, which sports a '63 car 289 motor, runs with a 7 lb. cap and seems very happy whether idling in traffic or cruisin' down the hwy


Well, it might be happy with a 4 pound cap, a 15 pound cap, or a no pound cap [^]. If the pressure ONLY raises the boiling point of the coolant (ie...doesn't LOWER the temperature of the coolant), and the coolant never gets to the boiling point, does it really make a difference?



http://i149.photobucket.com/albums/s66/ddstnkmp/54%20starlight/HiResS2Dsig2.jpg

Tom B
01-05-2008, 02:16 PM
The earlier 4 lb. radiator tanks will be smooth and "bulgy" while the later high pressure ones will have deep stiffening ribs in them.

Interesting, my 55 President, 259 4V has a rounded bulgy top tank on the radiator and a OLD radiator cap with a two digit pressure cap. The first digit is 1, I can't read the second digit. I remember reading, somewhere when I was planning on buying the 55 that they had 13 psi radiators. Mine looks like it was made bulgy to resist further bulging. I know I've seen this style top tank on other 55s, it is not unplanned. My 53 has the ribs and a 7 psi cap.


[img=left]http://www.alink.com/personal/tbredehoft/Bothcars3.jpg[/img=left]
Tom Bredehoft
'53 Commander Coupe
'55 President State Sedan (Under Construction)
'60 Lark VI (Sold, delivery in early Jan.)
'05 Legacy Ltd Wagon
All Indiana built cars

N8N
01-05-2008, 09:17 PM
well Tom I may have been mistaken about the style of tank, all I know is 53-54 look like you describe and use a 4 lb cap and my '55 has a deeply ribbed tank and uses a 13 lb. cap so I ASSumed that the neck was changed at the same time as the tank. I guess you'd have to check the service letter to be sure as this was not documented in the shop manual (and it drove me nuts, as I kept buying the wrong cap, as I did not know that 13 lb. caps were used prior to the '56 model year until I read through all the service letters!)

nate

--
55 Commander Starlight
http://members.cox.net/njnagel

Rerun
01-06-2008, 09:48 AM
quote:Well, it might be happy with a 4 pound cap, a 15 pound cap, or a no pound cap . If the pressure ONLY raises the boiling point of the coolant (ie...doesn't LOWER the temperature of the coolant), and the coolant never gets to the boiling point, does it really make a difference?


While the overall temperature of the coolant may be well below boiling, it is possible to have localized "hot spots" due to poor circulation in parts of the engine. If any of the coolant boils, it can create pressure throughout the system that will force coolant out through a low or no pressure cap. Also, just after a hot engine is shut off, there is often localized boiling as heat from the block/heads is absorbed by the coolant. This can cause coolant overflow if the system isn't pressurized sufficiently.

Jim Bradley
Lewistown PA
'64 Daytona HT "Rerun"
http://i226.photobucket.com/albums/dd35/bradley71771/Rerun.jpg

Dick Steinkamp
01-06-2008, 11:27 AM
Thanks, Jim....I'm starting to see the light. [^]

http://i149.photobucket.com/albums/s66/ddstnkmp/54%20starlight/HiResS2Dsig2.jpg

Neal in NM
01-06-2008, 09:59 PM
I see what you mean; understanding the boiling point of a liquid in a pressurized cooling system doesnt help understanding why. There are a couple of reasons for raising the boiling point; start with what is going on in the combustion chamber where temperatures can range from 850F to 1500F and sometimes higher, at these temperatures the water jacket side of the combustion chamber well exceeds the boiling point of water. If you start with the premise that steam is an insulator then each little bubble that forms on the water jacket side of the combustion chamber is acting like insulation blankets decreasing the efficiency of heat transfer to the coolant. By pressurizing the system these bubbles are diminished significantly.

Another point has to do with thermodynamics. The engine that makes a cooling system work is that heat wants to transfer from a hot location to a cool location to find its equilibrium if you will. The hotter the coolant is the faster it will move to the cooler location (the radiator) and be dissipated to the atmosphere by radiation to the air passing through.

If the outside air temp is 32F and the vehicles radiator is 190F you have a difference of 158F and the heat will dissipate well, but lets say you are in the Mojave during the summer and the ambient temp is 120F your difference is only 70F the outside air cannot adsorb the heat as readily as when it was 32F and snowing. Since we have established that if the pressure is increased, the boiling temperature is also increased therefore the coolant can be safely heated to a temperature well above 212F without boiling. The higher the temperature the coolant is, the larger the temperature difference between it and the outside air temperature will be. Therefore the efficiency of removing this waste heat is increased.

Just because a 185F thermostat is installed doesnt mean that the engine is going to run at that temperature, it is the temperature at which the thermostat is designed to open. With that said; the engine could be running at 212F without your knowledge, even with a temp gauge in the dash. Neal



[quote]Originally posted by Dick Steinkamp

I understand all that, Neal (thanks :)), but I still don't "get it" in real life applications.

I can't imagine any of us running our Studes at 250 degrees F. In fact, my newish GMC Sierra (my only non Stude with an actual temp gauge) runs at a consistent 210 degrees (hot days, cold days, towing, etc.)...and that is HOT compared to where we like to see our Studes run. Even it wouldn't theoretically need a pressurized system since the coolant never gets to the boiling point.

So...what advantage is a pressurized cooling system in a car (like our Studes) that run at 180-200 degrees F?. Raising the boiling point of the coolant with pressure doesn't seem to be a factor for us.

N8N
01-06-2008, 10:20 PM
after all this discussion about radiators, I went to start my '55 today and found green stuff on the fan :( guess it's time to get it properly serviced...

I wouldn't mind having a spare pair of tanks, anyone have a radiator laying around for a late '55 C-K?

nate

--
55 Commander Starlight
http://members.cox.net/njnagel

JLasvegas
01-08-2009, 08:42 PM
Does anyone have any pictures of coolant recovery resevoirs they are running on there Studebaker?

http://farm4.static.flickr.com/3153/3053270621_acbec95891_t.jpghttp://farm4.static.flickr.com/3027/3053282963_80ff432e9c_t.jpghttp://farm4.static.flickr.com/3289/3053279651_46c4f7971f_t.jpg
1964 Daytona Wagonaire
259cid flight o matic

StudeRich
01-08-2009, 09:43 PM
If you check at the top of Page 112 in the S.I. Catalog, you will see one of the most common and easily adapted systems available.

These are available at Studebaker Vendors and certain Auto parts Stores when you can find them.

http://i197.photobucket.com/albums/aa221/studerich/My64Daytona.jpg
StudeRich at Studebakers Northwest -Ferndale,WA

Bob Hutchins
01-08-2009, 10:20 PM
It's funny. I have a '49 champion with a 4# cap and aftermarket coolant recovery system that never marks it's territory, and a '57 T-bird with a 13# cap and aftermarket recovery system that I have to add antifreeze to every week. No bubbles in the antifreeze, but the car marks it's territory every time I drive it.

Bob

Robert L. Hutchins

champion52
01-08-2009, 11:31 PM
My 2 1/2 cents: Make sure to never fill the radiator completely. The top tank in the rad. acts as your expansion tank. I usually fill the rad. until 1/2 of the upper tank is full, leaving about 1 1/2" level below the fill neck.They were designed this way.
If you have coolant constantly draining from the overflow, you're probably not leaving enough room for the hot coolant to expand, especially when the car is shut off from a good run.
The external recovery tank will just catch this expanding coolant & send it back to the rad. when it cools, therby taking the place of the top expansion tank's job.
Making sure the coolant system is properly maintained & checking that you have the correct thermostat/rad.cap installed will have your Studebaker keeping it's cool!
My '52 Champion very rarely places a drop of coolant on the ground, even after those long runs.
Last point: If you install a 180 degree thermostat in a car that is designed to have a 170 degree, you will have raised the operating temp. of the coolant. The 180 one will not open till the coolant reaches 180. Even if the engine likes to run at 170, you prevent this because the flow of coolant is stopped until the coolant reaches 180. When the coolant again drops below 180, the lower temp. once again closes the thermostat & the coolant is forced to raise to 180. The cycle is repeated over & over. This is why the engineers of years past made sure to do all the testing for us to come up with the correct operating temperature for our cars.

Hawklover
07-20-2012, 11:04 PM
So on a Stude Avanti the expansion tank should be 3/4 full?
My 2 1/2 cents: Make sure to never fill the radiator completely. The top tank in the rad. acts as your expansion tank. I usually fill the rad. until 1/2 of the upper tank is full, leaving about 1 1/2" level below the fill neck.They were designed this way.
If you have coolant constantly draining from the overflow, you're probably not leaving enough room for the hot coolant to expand, especially when the car is shut off from a good run.
The external recovery tank will just catch this expanding coolant & send it back to the rad. when it cools, therby taking the place of the top expansion tank's job.
Making sure the coolant system is properly maintained & checking that you have the correct thermostat/rad.cap installed will have your Studebaker keeping it's cool!
My '52 Champion very rarely places a drop of coolant on the ground, even after those long runs.
Last point: If you install a 180 degree thermostat in a car that is designed to have a 170 degree, you will have raised the operating temp. of the coolant. The 180 one will not open till the coolant reaches 180. Even if the engine likes to run at 170, you prevent this because the flow of coolant is stopped until the coolant reaches 180. When the coolant again drops below 180, the lower temp. once again closes the thermostat & the coolant is forced to raise to 180. The cycle is repeated over & over. This is why the engineers of years past made sure to do all the testing for us to come up with the correct operating temperature for our cars.