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Just to get back to this, I have an IR Heat gun on order but its taking forever to get here... thus the life of a deployed Vette owner.
Anyway, my upper radiator hose doesn't seem to be "under pressure". Should it have some resistance when you squeeze it? It doesn't feel like water is running through...
Somebody suggested a new over flow cap. This made sense so I ordered and original style cap (the one on the car has the release opening on top).
The new cap made no difference....
A forum member who is going restomod with his 67 is sending me his Correct & Dated Radiator... he says it ran perfect in his car, but since its no longer needed, its mine for the shipping costs.
I thought that I would replace the water pump while I had the radiator out (A buddy gave me his unused aluminum sbc water pump... he needed a counter clockwise pump and the company sent him the regular one)
Just to get back to this, I have an IR Heat gun on order but its taking forever to get here... thus the life of a deployed Vette owner.
Anyway, my upper radiator hose doesn't seem to be "under pressure". Should it have some resistance when you squeeze it? It doesn't feel like water is running through...
Somebody suggested a new over flow cap. This made sense so I ordered and original style cap (the one on the car has the release opening on top).
The new cap made no difference....
A forum member who is going restomod with his 67 is sending me his Correct & Dated Radiator... he says it ran perfect in his car, but since its no longer needed, its mine for the shipping costs.
I thought that I would replace the water pump while I had the radiator out (A buddy gave me his unused aluminum sbc water pump... he needed a counter clockwise pump and the company sent him the regular one)
Yes, it should definitely have pressure and feel hot. It sounds like your thermostat may have failed closed. Have you tried removing it and testing it in boiling water?
Tux..
Yes, I put a new thermostat in.... I also tried it with out a thermostat and it was still hot.
Wow, sorry, I missed that.
Weird - if you've got no flow/temperature in your upper hose when the engine is hot and with no thermostat installed, then there is only one reason I can think of - your water pump isn't working properly.
Are you sure that pump your friend gave you is the right one/has the correct rotation? A pump with incorrect rotation will just try to push the coolant back into the block, not up through the thermostat and then to the upper hose/radiator.
If the problem was just your radiator being old and plugged up there should still be pressure and heat in the upper hose if the pump is working properly.
Last edited by tuxnharley; 09-25-2015 at 09:45 PM.
Reason: typo
A reverse rotation pump will not try to pump water back into your engine but the vanes are pointed the wrong way and the result is like a knife cutting through the water it is supposed to be pumping. You get some flow but not nearly enough and little pressure. It would act similar to the problem Rev Fan is having.
Is he sure this is hot? If the upper hose is not pressurized it does not sound hot.
Has it been spitting fluid on the ground after he parks it?
Checking your dwell and timing takes less than a half hour and should be ruled out long before changing your radiator. If your advance decided to stick it would certainly heat you up at RPM.
As others stated the fan clutch should not be in play at all when the car is above 45 MPH at that point you would have speed pushing air through the radiator with sufficient force.
Did you ever try the cool water mist test? It will tell you a lot about flow and cooling ability. It does make a mess out of a very clean car but water will dry and misting will not soak everything it just makes it damp.
I think every single one of us would love to drive the Autobahn in our Vette so we are all very jealous and Thank You for Serving our Country. Get it fixed and lets see a video of your Vette legally exceeding 100 MPH!
The upper hose is very hot to touch, it just doesn't feel pressurized.
Not spitting fluid at all... clean underneath
Have not done the mist test...
Will try to check dwell and timing... as soon as I fine a video walkthrough.. I have a timing light, what else do I need?
A dwell meter. Not real common anymore. You will probably need to order one, try Summit or Harbor Freight. Also an Allen wrench set to adjust the points/dwell.
If you can squeeze the lower rad hose with your hand (caution when hot) then there is no coil inside this hose. Under power the hose maybe collapsing and restricting water flow into the engine. If coolant is not flowing because of this restriction (upper hose really hot) your temperature will increase. Replace lower rad hose with a correct one with a spiral coil inside the hose.
Dwell is setting your points. They can also be set with a feeler gauge and you will be close enough if you don't have a dwell meter. Point gap is approximately .016 with used points or .019 if installing new points this should get you close to a dwell of 28-32 and is certainly close enough to drive the car with it running great. Set points before timing as others have mentioned. Changing points will change the timing so always do the points first. When you hook up the timing light and check your timing at idle also rev the engine while watching your timing so you can see if your advance is working in the distributor. It should move smoothly up with the RPM till your timing is at 35 degrees, plus or minus 1 degree at 3,500 RPM. Most distributors are fully advanced by 3,500 so you are safe if you see it advance to that point.
As another poster mentioned earlier in your thread if it does not advance you will heat up at freeway speeds. It would also use more gas and have less power but these cars have a lot of power for the weight and you might not notice.
The note on your lower hose might have legs, that could certainly cut flow and has many times in other cars.
Dwell is setting your points. They can also be set with a feeler gauge and you will be close enough if you don't have a dwell meter. Point gap is approximately .016 with used points or .019 if installing new points this should get you close to a dwell of 28-32 and is certainly close enough to drive the car with it running great. Set points before timing as others have mentioned. Changing points will change the timing so always do the points first. When you hook up the timing light and check your timing at idle also rev the engine while watching your timing so you can see if your advance is working in the distributor. It should move smoothly up with the RPM till your timing is at 35 degrees, plus or minus 1 degree at 3,500 RPM. Most distributors are fully advanced by 3,500 so you are safe if you see it advance to that point.
As another poster mentioned earlier in your thread if it does not advance you will heat up at freeway speeds. It would also use more gas and have less power but these cars have a lot of power for the weight and you might not notice.
The note on your lower hose might have legs, that could certainly cut flow and has many times in other cars.
But I think it would be easier for a first timer - presumably working by himself - to adjust the dwell thru the distributor window, using a meter while the car is running as a one person operation.
That as opposed to removing the distributor cap,cranking the engine to get the points rubbing block to stop exactly on the distributor cam high point, getting out of the car to see if it actually landed there,repeat as needed. Or have a remote start jumper to use, or a friend to sit in the car to crank it. All pure guess work and luck to get it to land in the correct place to use the feeler gauge
Plus, how are you gonna check the actual dwell without the meter anyway? Maybe we should tell him how to set the timing by ear, idle speed, and performance too?
If the car is a stick shift you put the car in 4th gear, emergency brake off and push the front tire with one hand and stop when the points are sitting on top of a peak. Works pretty easy on flat ground. That is how I would do it if working alone. If the car is an automatic a socket can always be put on the crankshaft to rotate the points to full open position for adjustment. A dwell meter is certainly the easy way but as mentioned, he does not have one.
I have a 61 Corvette with 327( not correct motor)/4bbl/4speed for 30 years and am having similar heating issues regarding the temp gauge. The car has never over heated but the temp gauge reads 220, and it still causes me concern. I will try some of the suggestions made on this thread. OP any follow up?
After my post I did about another 10 hours of reading about overheating on this forum. You guys rock! I learned more about cooling systems in a very short time. My infrared temp gauge just came from Amazon 1 hour ago. Tomorrow I'll see if I have a problem with overheating or not.
What ever engine you have, a 180 stat is the best fix for overheating....Too remove it is the wrong course of action as the water has to have time to lower the temp which is done with the radiator....Flow too fast or too much and the net result is overheating......The radiator could be the problem too...
whatever you do, is don't run without a stat....180 is preferred as a 160 does not hold the water back in radiator to properly cool it
1961 Corvette with 1963 327/ 4bbl/ manual trans. Owned 27 years, the last few years little use and gradual temp increases. Several years ago I put in a 180 thermostat (because of temps in the 220s), took it out, maybe I put it back??. I can't remember.
Except for the temp gauge, you wouldn't know there was a problem, although I started driving the car only when the ambient temps were in the 50-60's and terminated any prolonged excursions at 220 or above: doesn't puke coolant.
OK here is my data after using the infrared thermometer: I took the bottom hose temp from the rubber itself (is this accurate enough)
1. My Corvette temperature gauge correlates with the IR thermometer fairly close
2. Car at idle for 15 mins (outside temp 70 degrees) bottom hose 120/therm housing 150
3. After 15 mins highway: bottom hose 145/ therm housing 220
4. After a shower on the radiator with garden hose for 5 mins, bottom 135/therm housing 180
5. Fan clutch cold with quick flick of the wrist: blade moves from 10 o'clock to 2 position, actually does the same thing and feels the same when at 220 degrees.
If the radiator is partially clogged should I have "relatively cool temps" at the bottom hose as above? With above data even if the therm was out should I just order the replacement radiator or make sure I have a 180 in place first and repeat? Should I replace the fan clutch? I must confess, I haven't been as attentive as I should have been to the coolant changes over the years. Water pump?? Essentially the cooling system contains the same components over the last 27 years (except the thermostat) which it may or may not have; the radiator is Harrison aluminum, heater hose etc. set up correctly, expansion tank cap unfortunately is generic 13lb.
I wonder if 27 years with little care has eaten the vanes off your water pump.
Old antifreeze gets a high acid content and is hard on parts.
Radiator seems to be cooling but your flow seems slow.
I would certainly start at the thermostat, if installed it may be stuck partially open.
While in there a good flush can't hurt. I would hold off installing new anti freeze and run with straight water while figuring it out. Hopefully a freeze does not come soon!
I wonder if 27 years with little care has eaten the vanes off your water pump.
Old antifreeze gets a high acid content and is hard on parts.
Radiator seems to be cooling but your flow seems slow.
I would certainly start at the thermostat, if installed it may be stuck partially open.
While in there a good flush can't hurt. I would hold off installing new anti freeze and run with straight water while figuring it out. Hopefully a freeze does not come soon!
Well I haven't been that delinquent. I changed the antifreeze about 6 years ago and have been servicing the car fairly regularly over the last 27 years. I am in San Antonio so hard freezes are rare but do occur sometimes for a couple of days in January. If I had a coolant flow problem as opposed to a clogged radiator, would the temp drop 40 degrees that fast with a cool shower on the radiator? I'll check for that thermostat.
What ever engine you have, a 180 stat is the best fix for overheating....Too remove it is the wrong course of action as the water has to have time to lower the temp which is done with the radiator....Flow too fast or too much and the net result is overheating......The radiator could be the problem too...
whatever you do, is don't run without a stat....180 is preferred as a 160 does not hold the water back in radiator to properly cool it
I get how a 180 thermostat will help an engine warm up quicker and stay warm. How could it be a fix of any kind for overheating? Or any thermostat really? Isn't it's purpose to redirect water flow and keep it within the engine till the coolant heats up. Then it opens at temp and allows flow into the radiator to cool it. "Flow too much or too fast", would give less time in the engine to heat up before getting to the rad to cool it down.
Most thermostats flow exactly the same amount when open, or very close to the exact amount.
You can run any temp you wish the flow will work fine.
Boats run thermostats at 140 because fresh water will cause more rusting if run hotter.
I have run 160 to 220 in various cars, they all work if the system works.
I only ran the 220 because my 160 stuck and I had the 220 on the shelf in my garage so in it went. The heater was awesome that winter. I changed it later but I did run 220 a little in summer and the whole winter. The cooling system did not seem to care.
The factories have pretty much settled on 195 because it lets the engine run more efficiently. I have been told there is less heating and expanding inside the block when the running temp is warmer, 195. Beyond that showed no benefit I was told.
First, my Timing Light is Kaput... so I am awaiting the arrival of one I bought and is being shipped from the States... So, no, I don't know what the timing is, but, for whatever its worth, my Mechanic Friend and 66 Corvette owner buddy who is also stationed here has helped me with the car and doesn't believe that there is a problem with the timing... Still, I will check it when the light comes....
Anyway.
It has taken forever, but my IR Gun came. I pulled the car out of the garage, cool autumn day, and monkeyed around in the garage for a bit (10 mins TOPS) for the car to get up to temp.
A few minutes later, I got the IR gun and shot the top of the Radiator where the big hose goes in... it was about 55 or outside air temp, same with the other side at the outlet hose. I squeezed the big Radiator hose and it didn't feel under pressure. I checked the Dash Tem[ reading and HOLY COW IT WAS ALMOST TO THE YELLOW!!!!!!
I shut the car off. I went inside to get a notebook and sketched a motor to keep track of where I was going to shoot the temps. And after a few minutes... maybe 5 Total, I started the car up again and it was about 190 when it first started.
This time, it was different. The Radiator Hose was under pressure. It got hot, but even after a few minutes it was only about... 220?
Here are the places where I shot the car and the temperature it recorded.... but it seemed to settle back at around 213-ish when these photos were taken.
You can see, not much time is expiring between these swings.
For grins, I turned on the heater, and it dropped down to maybe 211?
Did this muddy the waters up more, or does it help point in a direction? I have a new water pump that I will put on.... I had bought a used but good 67 Radiator, but before it could be shipped to me, it was a victim of the last hurricane when a tree fell through the sellers garage.
09-25-2015, 02:55 AM
But I think it would be easier for a first timer - presumably working by himself - to adjust the dwell thru the distributor window, using a meter while the car is running as a one person operation. 
