OVERHEATING/RADIATOR REPAIR - Squarebody Chevy

[@timashworth3794]

I love ❤️ your videos maybe a larger exhaust system and maybe a cold air intake

[@SquarebodyTruckCamper]

@@timashworth3794 thanks for the advice and comment!

[@vintage76vipergreenBeetle]

A all aluminum radiator, is what that truck needs.

[@SquarebodyTruckCamper]

@@vintage76vipergreenBeetle if I still have overheating issues in the future, I will investigate replacement radiator options. Thanks for the comment!

[@Pattersonm29]

I bought a 3 core aluminum champion radiator, inexpensive yes, cheaply made no. I have one on my 1984 f-250 4x4 6.9 idi, I've towed heavy through utah and into idaho without overheating, several times. If you have any questions let me know. I think i paid 250-300 for the champion and the radiator shop wanted 800 to rebuild the original brass one.

[@SquarebodyTruckCamper]

@@Pattersonm29 wow, so you got a similar quote that I did to have a brass radiator rebuilt. If I am still having issues with overheating, I will investigate replacement radiator options. Thanks for the comment

[@ElGuaposTruckFarm]

Throwing out a few ideas that you may or may not have already checked... Maybe I missed it, but did you do anything to break up the calcium and scale in the radiator when you flushed it? If it's consistently overheating but you have sufficient water flow, it may not be dissipating the heat quickly enough when the engine is under heavy load. Even though it's not clogged with a complete blockage, that coating of buildup between the internal passages will certainly affect the heat dissipation capacity. Also, is the heater still not working well? If not, maybe the water pump isn't moving the coolant efficiently anymore? If it's really old, the impellers inside can rust out and it won't flow as well. How is the fan clutch? Still have good resistance and not just letting the fan spin free? It does look like the fan shroud may have a lot of extra space between it and the end of the fan blades, so it likely isn't drawing as much air through the radiator as it should. I'm guessing that's a big block fan shroud with the small block clutch fan, so there'd be about 2" too much space around the outside edge of the fan which will reduce the suction that draws the air in. Lastly, I didn't notice it in the video, but have you checked or replaced the lower radiator hose? Make sure it's not collapsing and restricting coolant flow. Just a few of the things I've run into over the years that you might not have checked yet! Love the camper setup, and really enjoy the videos!

[@SquarebodyTruckCamper]

@@ElGuaposTruckFarm thanks for the in depth comment and advice. I have done some of the things you advised, but not all. 1) I was warned from the radiator shop about the scale build up potentially not allowing heat dissipation. If I am still having overheating issues after I try a bunch of other things, I will replace the radiator. 2) I did not use any products to break up the scale in the radiator when I was flushing it. 3) I actually haven’t checked if the heater core is working better now that I have flushed the radiator, I need to try that still. 4) The flow coming out of the heater core back into the radiator seems sufficient to me. It’s flowing like a half opened garden hose. I know that’s not a scientific flow rate, but it is a decent amount in my opinion. 5)fan clutch with 3 blade fan is what I used to have on truck. I replaced with a clutch and 5 blade fan off of a big block and it definitely moved more air when the truck is sitting still. But it only is overheating when under heavy loads pulling hills going over 50mph. So the fan clutch and fan replacement did not solve the higher speed overheating symptom. 6) the fan shroud originally was on a K20 when I got it. I then cut it down so that half of the fan blades were exposed so it would flow correctly. The ends of the fan blades to the shroud may need to be brought in closer (there is currently about 2-3” gap). I figured with the Ram air effect when driving 50mph+ would make the fan shroud not the most important piece to the overheating issue. 7) I have not replaced the lower rad hose. I do not know if it is collapsing, is there a good way to tell if that is occurring?

[@ElGuaposTruckFarm]

@@SquarebodyTruckCamper I agree the fan is not the likely culprit here since you have airflow over the radiator when it's moving, that was mostly an observation I threw out there as something I'd noticed. I really think the most likely culprit is the scale in the radiator. A half decent aluminum radiator will likely cure the issue, but make sure and replace the upper and lower hoses at the same time. The flow from the heater core won't really have much bearing on anything as the bulk of the coolant is just cycling through the upper and lower radiator hoses. In fact, on my squares I usually install an inline valve on the heater hose coming from the engine to keep the hot water from even going through the heater core. A lot of those old trucks will still circulate air over the heater core and blow unwanted hot air on you all summer! On the lower hose, if it's overheating just crawl underneath and you'll likely be able to see or feel if the hose is collapsed. They should have a spring inside of them that adds structure and holds them open, but the springs can corrode and break down over time too. You may also try replacing the radiator cap itself and add an overflow tank with a hose from the small hose barb below the radiator cap. The radiator cap needs to allow the cooling system to hold pressure, and when it gets hot it should vent excess coolant into that tank, then suck it back into the system as it cools again so long as the radiator cap isn't venting all the pressure out. kzbin.info/www/bejne/jmrPYYijn5eGoq8 Here's a good article and visual of how they function and why it helps with cooling. I would absolutely add an overflow tank of some sort: blog.championcooling.com/2018/06/08/overflow-tank-vs-expansion-tank/ You can literally throw one together for nothing to test it out too: www.jalopyjournal.com/forum/threads/what-do-you-use-for-a-radiator-overflow-bottle.1057563/

[@SquarebodyTruckCamper]

@@ElGuaposTruckFarm great advice. I will see if I can get a rad overflow next time I go to salvage yard. Next time my truck is getting warm I can pull over and try to see if lower rad hose it collapsing .

[@larry04456]

Okay, advise from an old square body guy first if you think you need a radiator, get on line and look up a complete aluminum radiator 2nd buy what i have seen on couple of your videos the noise you're hearing is probably spark nocking whick means your timing is of and the way it starts kinda confirmed that and with the timing being off will also raise the temperature especially under load .my guess is that you need to advance your timing

[@SquarebodyTruckCamper]

@@larry04456 thank you for the advice. Stay tuned for the video that will post tonight for the timing/ignition update. Thanks again for the comment!

[@honest8bob]

I know people love to try and save the brass rads but I just dont think its worth it. The aluminum/plastic ones last long enough and perform just as well.

[@SquarebodyTruckCamper]

@@honest8bob if I rule out that the radiator is actually my problem, I will look into replacement options. Thanks for comment.

[@6789olds]

Get a160

[@SquarebodyTruckCamper]

@@6789olds thanks for the tip. I did change the thermostat to 160