Hello everybody this is my first post,I'm in sunny Florida and have noticed my 36 gets to 180 degrees fairly fast and even higher in traffic and then a slight boil over.I've checked the themostat and even put in a new 160 degree thermostst. Just flushed the radiator and will try her out again soon,the radiator could be slightly plugged but appears to flow water out fairly fast,I'm debating pulling it to have it cleaned/rodded out but it appears to be a little job to remove.What temps do your cars run ?

That is about where my 1934 & 1939 run in hot weather.In traffic they can go above the 180 mark but never throw out any water.I do have a 50% mixture of anti-freeze in them.Also have an overflow tank on the 39 but when I was out west in the mountains is the only time it ever threw out a little water(after it was shut off). I did install a new radiator in the 39 years ago And run 160 thermostats in my cars.

Hello Chevy Nut! does it make a difference in temperature of your coolant if you have an olive drab overflow tank or a gray one with orange writing? He!He!

Well I prefer the gray as it matches the engine color and does not confuse the coolant as it makes its travels.I hate it when both the driver and coolant are confused.

Yeah, Gene, one outah two isn't all that bad,specially if one of the two is color blind!

36 Coupe
There are a couple of proven (to me at least) mehtods of testing whether radiators are working efficiently
The 1st is a lot easier to test on early models with no grille. When car is hot, near or at boiling temperature, place the palm of your hand over the suface area of the core to see whether the heat is even accross the core. If you notice any cool spots then the radiator needs cleaning out or replacing.
The second method is easier on models with grilles and I have carried it out on my 34. It is preferable to have someone help you carry this out.
When radiator is cold drain all water, remove both hoses, place a hand over both inlet and outlet pipes and get someone to refill the radiator. When it is full remove your hand quickly from the bottom outlet and see how far the water shoots upwards. If it shoots up about 1 foot, then the water is travelling through the core efficiently, anything lower means less efficient flow, and if it just trickles over the end of the pipe, then the radiator is stuffed (aussie term for 'no good')
Hope you can understand all this.
I have tried on my 34 and my 28 and can recommend it.
Chris

my 36 has no overheating troubles, in fact I had to fit a thermostat to get it to warm up. Invariably the block is full of crud if the car has not been used for many years and this will block your radiator when you take if for a decent run.

From Sunny Australia

Thanks to everyone that replied,I've been working on the cooling system this a.m.and am pretty sure its stopped up.Did the hands over the radiator inlet and outlet test and the water came out at best 2 inches above the bottom outlet,been flushing it out for about 15 minutes from top to bottom and will be adding some super flush in about 2 hours and then drive it awhile to see if this will break down the sludge inside the block/radiator.If this doesn't do it I'll try flushing the block and radiator under pressure,last of all I'll pull the radiator and take in for evaluation at a shop that frequently does antique Chevy radiators.Thanks again and a Happy 4th to all!!

be really careful putting any pressure on your radiator. It is not a pressure vessel!!!!

If you really want to do the job right then remove the back welsh plugs and clean out the block. There is one plug above the flywheel housing that you access by pulling the gearbox cover out and an other is under the inlet manifold near the water drain tap. Fit a tube to an airline and feed it into the block while running water through the block. It is a must to do this if you are fitting a new radiator. I don't think you can clean the original radiators by rodding them as the tibes don't go straight through.

Good luck

Ken

The last reply is right on.The rariator acts like a filter catching the rust that is coming loose in the block.The rust could only plug up the new radiator.I have seen many cars with this problem over the years and have found the following to work.First use either Prestone Heavy Duty cleaner or #7 heavy duty cooling system cleaner.They are a round can 6" tall and in powder form.The contents in the top half of the can is used first(oxalic acid) and that is followed by a flush with the contents in the bottom of the can (sodium carbonate) a neutralizer).
You may try to remove the block drain cock (lower left side of engine just in front of exhaust pipe on 1936) and poke a wire in there to get it to flush better.
this product is the only one I have ever had luck with--The liquids are only for regular maintence on modern cars.If you give it two treatments or put in two cans at once it will not harm anything.Getting the loose rust of of the block is important--it will be impossible to get all of it out but this will do the best job short of taking the engine out and having the block cooked out.

Gene, I believe you are on the right track,
(1) because of the fragile condition of these radiators) and the way they act as a filter. a flushing operation on the block needs to be done with the radiator isolated from the block.
(2)The fact that there is a problem of tearing down the engine and having it boiled out. Shops that boil out engines are scarcer than hen's teeth because of the environmental impact that boiling causes, other methods are not as good, we are seeing engines rebuilt by large shops that are comeing back dirty and full of grime and caked up rust.
(3) when a hobbyist does a good job of flushing and cleaning his engine block he will notice a very positive change in the performance of his cooling system.
Lastly , it should not be too difficult of a task to devise a good home style flushing method useing the products such as you mentioned and a gravity low pressure flow system after the soft plugs are removed, which should be done anyway after they have been in an engine for 50 or 60 years.
Maybe that would be a good project to investigate and also get the procedure published in the G&D.
Any volunteers?
please explore this subject, and maybe try it at our home shops and get back together for futher discussions.
I have a 1957 261 engine in a truck that is going to be a candidate for this type of operation.

What do you other members think about this task?

Hello all,the block was clogged up to the point where nothing would flow out of the drain cock so I removed the entire drain assy.,then isolated the radiator from the rest of the sys.I used some rubber plugs with holes to fit around the air hose rubber nozzle and water hose nozzle for a tight fit,I also removed the thermostst housing and thermostat to flush the head to block passage ways,large plug required here.After several minutes of water bubbling the block clog broke free and rusty dirty water came gushing out the drain hole.I then started flushing through the temp.sending hole on the top left rear of the head and repeated all till clean water flowed clean and fast.Now to the radiator.I pulled the radiator yesterday a.m. and looked it over closely and it has all the tell tale signs of needing repair,the bottom tank is seeping in a couple places as well as the core and may possibly be the orignal.Its plugged pretty bad to wear you can hear the water working its way through the passage ways and actually see the water in the filler neck slowly drop.I'm in Jacksonville Fl.and there are several places that still boil radiators out,I also found a place that makes new cores locally so I'll check into each Monday and hope to have it back no later than Tuesday.I'm wanting to take it to a local antique/classic show next weekend.This Standard coupe is in very good condition and runs great,it just hasn't been driven enough in the past 10 years or so.I'll keep everyone posted on the progress.Thanks for all the input,it was very helpful and appreciated.

36 coupe, sounds like you have all your ducks in a row!, I would like to see pics of your coupe at the show, I think we all would.

HEY MR MACK, IF YOU GOT ALL YOUR DUCKS IN A ROW??? HE WILL HAVE PLENTY OF TIME TO LOAD AND RELOAD THE CANNON, YA

Hey Donald! A canon? What canon?? Does it have a Chevy bow tie on it? If so.....let's do it! Ya! ha ha!!

First of all Donald our ducks here in Texas aren't that kind of ducks, they just quack and quack, and waddle on down the road in a row. and if you haven't met a Texas Game Warden You ain't lived yet.
JunkYardDog lets just burry the hatchet

Congratulations 1936 coupe you seem to be dong all the right things.When you get done you will be able to give us a few pointers. Just to relate a story that happened to me. In 1981 we were returning from the 15th anniversary meet in Pa.Another person in our caravan was having an overheating problem such as yours.Each time we would stop to cool off his car I would open the hood of my 39 to check things out.I saw a small crack forming in the water jacket under the exhaust manifold.By the time we arrived home it was over a foot long with .I added sealer and drove that way for another year.Lucky to find a new bare block I transfered all the internal parts over and was back on the road .One day I decieded to see what was behind the crack in the old block so took a big hammer and beat a hole in the water jacket only to find the lower 3 inches of the water jacket was filled with rust.Never had an overheating problem with the car (was to Colorado and went up to the top of Pikes Peak OK) so was surprised to find so much rust. When I started working in the Chev. dealership in 1950 in was not unusual to find 3 & 4 year old cars with pluged-up radiators.The anti-freeze had very little rust inhibitors in them and some cars were run with only water for the summer seasons causing rust buld-up.That is why it is recommened t run a 50-50 antifreeze mixture which will help tp prevent rust.
also to change it every 2 or 3 years. P.S. Yes Mr. Mack it would make a good G&D article.I will have to add it to my list of subjects to write about.Hope to get time this winter

Hey Macky Wacky! What hatchet? I ain't got no hatchet! Will a pair of pliers and a screwdriver do???

JunkYardDog, sounds lack You got a complete Okie restoration tool kit..... and before you other Okies get them bristles on the back of your red-necks standing straight out I was born in Tonkawa!

Tonkawa?? Is that where they make them there Tonka toys????

Nah!
About they make there now-a-days is little Okies! (some of them are Hydra-matic Okies!)
know what I mean?

Hello all,here's the official 36 Coupe radiator update.The local wholesale distributor referred me to a familiar radiator shop for core warranty reasons.I walked in carrying the radiator and the shop owner immidiately recognized it

Further to my earlier post, I have seen many engine blocks that have been full of crud at the back as high as the cylinder head. The only way to properly clean them is to remove the plugs at the back of the block and insert a high pressure airline while running water through at the same time. I made up a tool using a piece of nylon truck brake air hose fitted to the end of my compressor hose. This works well as it is strong and flexible so you can push it right around the cylinders inside the water jacket. You need to do this even if you get the block chemically cleaned as there will still be some crud left behind.

Ken fom sunny Australia

R-36, That is a good idea, I hadn't thought of useing that kind of tubing, I also use brushes where I can. do you use any special flush soap or chemicals or just water?