Puzzling overheating

[jkresse]

Has anyone mentioned thermostat? I had a similar problem in my '53 Commander: it would get hot on the highway and then stay hot. Turned out to be a faulty thermostat!
Joe Kresse

[bezhawk]

Just a technical discussion not a criticism. My understanding of the spark advance system is, the vacuum advance, aka spark modifier, is that it offers an advanced spark earlier at lower speeds and if it failed ie hole in diaphragm, there would be no advance at lower speeds and therefore the spark would remain somewhat retarded for the speed. I don't think this condition would cause overheating. The secondary level of advancement is the centrifugal weights and counter springs. There are two forces working against each other centrifugual ie the weights and the springs to counter the weights to control the amount of advance. If a spring is broken the remaining spring cannot counter the forces of the centrifugal weights and therfore an excessive advance condition is created, and therefore the excessive advance condition will cause overheating. This is my understanding Dave

Excessive retarded timing can also cause overheating. I have seen many people set the timing with the advance hooked up. Since there is high vacuum @ idle, the advance does come into play. Take away the advance, and the timing will be set too slow. The centrifugal advance comes into play as the engine is at a higher rpm than when you set it.(the timing). It's easy to plot with a timing light and a tachometer.

Just a note that might only show up on 1 in a million. I got my 59 Lark and went through it, only because I had never had a six before, but to my surprise the head gasket was on backwards. Yes it can be done. If one does not read the direction on the gasket it's self. This puts a smaller hole in the wrong spot and inhibits the proper flow through the head. I didn't have any problem before but I had not put many miles on it. After owning it for almost ten years not it still has under 35K miles.

[dtracy]

Thank you for that part number. I can't find any other vendors who sell a sending unit for this engine. S.I. doesn't list it either but I'll call and hope.

The engine isn't the issue because both the 6 and the 8 cylinder engines used the same guage, the guage/sending unit and voltage is. I don't recall reading anywhere in the posts the voltage of your system. If it is 12 volts and was originally 12 volts, and your existing sending is the 3/4 NPT, the 3/8 NPT could be used with 3/4 to 3/8 bushing.

On your previous question regarding the exaust gases in the system without the loss of coolant, pressure from highest to lowest is the answer. The combustion gases are over 100 psi while the coolant pressure is maybe 8 to 12 psi. The gases can be forced into the cooling system while the coolant may never leak back past a bad gasket. I don't think you have a blown head gasket however as you lack other crucial symptoms of the diagnosis.

The issue with the lower radiator hose is not its age but rather the existance of the anti-collapse spring. It needs to be there, new or not.

I think you are on the right track though with the defective sending unit. Borrow the wifes cooking thermometer and carefully remove the radiator cap. Insert the thermometer and take a reading. Compare to inside temperature reading.

Dave.

[altair]

spark advance

If the timing is off, it will cause it to run hot too. Check the vacuum advance, the diaphragm can rupture without any visual clues.

Just a technical discussion not a criticism. My understanding of the spark advance system is, the vacuum advance, aka spark modifier, is that it offers an advanced spark earlier at lower speeds and if it failed ie hole in diaphragm, there would be no advance at lower speeds and therefore the spark would remain somewhat retarded for the speed. I don't think this condition would cause overheating. The secondary level of advancement is the centrifugal weights and counter springs. There are two forces working against each other centrifugual ie the weights and the springs to counter the weights to control the amount of advance. If a spring is broken the remaining spring cannot counter the forces of the centrifugal weights and therfore an excessive advance condition is created, and therefore the excessive advance condition will cause overheating. This is my understanding Dave

[jgrohs]

try Studebakers West if you haven't already.

[K Russell]

Thank you for that part number. I can't find any other vendors who sell a sending unit for this engine. S.I. doesn't list it either but I'll call and hope.

[JoeHall]

Really want to make sure it is actually at that temperature. Local flaps around here always have an infra-red thermometer behind the counter.

Other question would be this: Is this high temperature seen only when the car is running down the road? Does it cool down when the car/engine are running at slower speed - say in town or similar?

My '60 with L6 will run warmer going down the road at 60 mph. When you get off the highway it will come back down to mid-gauge or lower. My Dad said the 1950 Champion my grandparents had would always run at 3/4 on the heat gauge during the Texas summers. He said the instant you got into town it would start creep down. If you stopped at a stop light for a minute it would go back down to normal.

Good luck

That was exactly my experience about 25 years ago, on the interstate, with a 1960 lark, 3 speed, that only had 40,000 miles on in. I tried all I could think of: new radiator, hoses, head gasket, 3.31 rear end, premium gas with octane booster, etc.. Nothing ever changed. If pushed to 65 mph for long, the needle would climb to where it would begin to detonate. Only slowing to 45-50 mph a few miles would help. Around town it was great. After a few thousand miles of limping it along, I sold it, and have never had another six cylinder Stude since. Good luck trying to fix it. I doubt it's broke. Just the nature of that little six.

[StudeRich]

1539876 is the correct Temp. Sender for a '56 or '57 Champion 185 6, you did not say what you have. If you check other Stude. Vendors and or ask at S.I. you can get one.

If I remember correctly, this is the Larger one, probably 1/2 inch pipe thread, the later Engines use I believe a 3/8 inch pipe thread smaller unit.

[K Russell]

OK, getting a reading on that sending unit that tells me it's probably the culprit. Where to get one? Can't find any online from any sources, nothing at Studebaker Int'l for the 6cyl. engine after 1955, other than the truck engine

[altair]

over heating

I flushed out my cooling system in my Champion 6, removed the drain plugs and found very little crud in the system, then installed a new water pump from Studebaker Int'l a couple months ago. The high coolant temps of the past disappeared, running at 180-190 degrees after the job was completed. About 250 miles later though, the gauge reading has steadily climbed to 210, or slightly higher if I've been running at steady highway speeds for even 10 minutes. Such a change in such a short time tells me something is definitely wrong but since I'm seeing no loss of coolant out of the overflow after stopping, I'm wondering if it's possible the sending unit has suddenly failed, resulting in a high reading, or are there other areas I should be looking at? I've never had a thermostat fail in the summer but since this has been a 3 week transition it wouldn't seem like that could be the answer, or could it be?

I experienced the same thing in a 6 pickup I finally traced it to a broken spring in the distributor advance mechanism Dave

[WCP]

Before wasting time and spending money unnecessarily, check the resistance of the sending unit at room temperature. They do go bad by losing resistance, causing the temperature gauge reading to rise. Eventually the gauge will peg and at that point it should be disconnected at the sender, to save the gauge. If that proves not to be the cause, then proceed with the other suggestions from posts 2-8.
Disconnect the lead to the sending unit at the sending unit and check the resistance with a simple multimeter from the brass terminal to the engine block. You should read 780-800 ohms at 68-70F for a 12 volt system. If your reading is considerably lower than that, then you have found the problem. Acquire a new sending unit. This should always be the 1st thing to check on a suspected over-heating issue, particularly when no loss of coolant is observed.
If your vehicle is 6 volt, then the resistance values may be different, but the same advice applies.

[warrlaw1]

Also, any brake drag will cause it to get hot. Once I solved that problem and put a more modern core in the rad, mine's staying cool. Good luck.

[bezhawk]

If the timing is off, it will cause it to run hot too. Check the vacuum advance, the diaphragm can rupture without any visual clues.

[K Russell]

@ rkapteyn, if exhaust gases are getting into the coolant, wouldn't the inverse be true also that coolant is escaping from a bad gasket? There's been zero loss of coolant so far. @ 62champ, I'll check on that infra-red device, thanks; it runs up near 210 (if the gauge is right) around town also, where 3 weeks ago it was running at 180, a slight increase in temp out on the highway. @ Gunslinger, the lower hose is brand new.