Re: Radiator Overheating
 

Saved plugged radiators by back flushing with an industrial hot water pressure washer using chemical degreaser.The best way to insure a repair is to remove the radiator and cylinder head,clean the water jacket,(i use compressed air and a speedometer cable on a drill motor to snake the passages).iv gotten twigs,rocks and all kinds of grunge from water pump grease rust and dirt coagulating..chemical flushing like you are doing is fine,and if it works,great...if it doesnt you need to go deeper

Re: Radiator Overheating
 

You're the second person to tell me bout removing the head and clean the water jackets. Lye has been mentioned for a real good cleaning. I'm actually due to pull the engine for re-bappiting. I'm sure I'll hit all of that good stuff at that time anyway...

Re: Radiator Overheating
 

Sometimes the amount of build up requires multiple treatments. Cylinder 4 jackets are usually the worst. Cylinder 4 comparatively has poorer circulation than the other cylinders. In some cases a speedometer cable flayed on the end is used with a drill to break up the deposits. There are also other methods.



A rough idea of how bad it is is to remove the hose necks on the head and block, and see what things look like. Additionally you can take the water pump off and give a look/see. For further inspection use an inexpensive borescope through the openings to probe deeper into the head and block.



When I had issues, tried white vinegar and thermocure. When using white vinegar you have to do a final treatment with baking soda/water to neutralize the acidic content of the vinegar, required because it works into the pores of the metal and is not flushed during draining/flush/back-flush. Downsides of vinegar - it can wash out the grease in your water pump, and if running the motor it creates a huge rusty water mess and can ruin paint. It also can cause rust flakes so you want to insure your coolant filter is installed if running the motor.


Nice thing about Thermocure and Rust 911 are they are not acidic and will not hurt anything metal/seals or rubber/vinyl, and should not flush the grease out of the water pump. Water/baking soda flush not needed. It typically does not cause flakes, they kinda "disolve" the rust into the solution, less chance of plugging up a radiator. Still recommend running a filter if running the motor.



The method of taking the radiator off is also a good way to do it, add solution to the radiator and and block after sealing them. Let them soak. Ive even heard of those who hook up a small circulation pump with a timer to circulate the liquid to increase the effectiveness of the solution.


I was just lazy and did as like above with the system together and ran my truck every day for 20 or more minutes with solution in it for a week or 2.


After 3 months of on off treatments and getting a ton of rust out discovered someone had put in an undersized 2 row core radiator. Had to replace it. However all my flushing raised the overheating speed from 25 mph to 45 mph, so it was still a good thing. Got a Bergs, and now have to run a 160 degree thermostat or the truck mostly will not get up to operating temps.

Re: Radiator Overheating
 

Forgot to mention, not sure if it was covered, bad head gasket will also cause overheating if exhaust gasses makes their way into the coolant. In bad cases you can see air bubbles in the coolant with the motor running. Do a compression test. Best way is to use a block test kit
https://www.amazon.com/Block-Tester-.../dp/B01N1NA22J

Re: Radiator Overheating
 

I like the idea of the block tester. When momma lets me get a high compression head I'll be replacing the gasket anyway:rolleyes: But this tester will work on a Model A even though it isn't a closed system?

Re: Radiator Overheating
 

I have been to your movie a couple of times. Old radiators are not your friend. They create an overheated engine and driver.

After much grief, I purchased a 4 row radiator from Bert's Model A Center. I live in 100 degree summer heat. I know a new radiator is not cheap but it is worth every penny.

I drove my A to the Reno/Sparks MAFCA convention in 2018. It was in the high 90's every day. Took tours to Virginia City and over the 7,500 elevation pass to Lake Tahoe. My A never went over 180 degrees. So, you can try to make your old radiator work or buy a new one.....I vote for a new one!

Re: Radiator Overheating
 

Yes, the test actually draws in the air in the top of the radiator through a test liquid in the tube, and detects for exhaust gasses.


If the test passes, you can pour the liquid back into the bottle. From what I remember, the kit will do quite few tests even if you do not reuse the liquid. I used it once, then donated it to a Club I am in.



The liquid does have a shelf life of a few years, and should not be stored in an unheated garage/area.


Another option is to call your local mechanics/radiator shop and see if they can test. May cost a little more - who knows.

Re: Radiator Overheating
 

[QUOTE=Dick M;1906244]I have been to your movie a couple of times. Old radiators are not your friend. They create an overheated engine and driver.

X2
It may have been mentioned above, even if the tubes are reasonable open, old radiators lose the contact between the fins and tubes. At that point it is either time for a new radiator or have the radiator restored with a new core.


And like Dick M posts, too many instances of high temps/overheating and you create other damaging issues to the motor.

Re: Radiator Overheating
 

Don't try to pressurize the system with the radiator in place. It is not designed for pressure and anything over a couple of pounds of pressure could very well damage the radiator.

Re: Radiator Overheating
 

Good afternoon...It is good to keep in mind that radiators made today can have a lot more capacity to cool than the ones that came originally. As a note, the AA's had larger radiators because they had to work so hard. A modern four row, 10 fins per inch, and a good thermostat and you will be in good shape...assuming that your engine's water jacket and head water jacket are clean and you timing is correct.

I once was asked to clean an old block in the engine shop where I just mess around and wash parts for something to do on Friday's. I took compressed air to the block and head and filled the shop with all sorts of orange air and a million small bits of God only knows what...and this is sort of normal! If you have an engine that has been out of use and will not cool...take the head off and blow and power wash the inside of the head and the block before anything else. You certainly don't want all that junk in your nice new radiator. Ernie in Arizona