Overheating issues 1600

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bossbob
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Re: Overheating issues 1600

Post by bossbob »

CT, what is the follow up on your heating issue, is it resolved, what did you do.

I have a similar situation with my 1600. Stock radiator, car hadn't run in who know's how many years. Got it running last summer and it was running cool mid range on the temp gauge, now it's up to the top of the gauge. I put my temp gun on it, and at the water neck it's around 240 which is also where the temp sending unit is, which seams to match the gauge. Along the head it's around 175. Top hose going into the radiator 175, as I move across the radiator it gets cooler by the time I get to the bottom of the radiator it's at 85. Bypass hoses are hot can't remember the temps. Lower hose is cool to the touch.

I'm thinking that after it sat for such a long time, and now that I have it running, whatever scale might have been in the block is now in the radiator and blocking the flow. Unfortunately, I haven't found a way to really look into the radiator itself yet to verify any clogging. I have burped it a gazillion times and tried every which way to be sure there are no air pockets in the system.

Good news, I guess, is that I rebuilt the rear brake cylinders and my brakes are working again.
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greydog
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Re: Overheating issues 1600

Post by greydog »

you might try a reverse radiator flush....connect a hose to the bottom of the radiator and let it push water out the inlet. Messy but can be effective. Don't pressurize the radiator with your hose (city water pressure is not good for radiators).
There are various chemical radiator flushing products available. I haven't tried them, preferring instead to do the old hot rodders treatment (white vinegar).
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Re: Overheating issues 1600

Post by jamesw »

Try the RidLyme product. Boaters (like me) Swear by it.
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bossbob
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Re: Overheating issues 1600

Post by bossbob »

Thanks,

I think I want to see if I can get a camera or something in the radiator to see what I see. I'm kinda thinking that whatever scale that may have come loose has been caught in the cooling fins of the radiator, and only a radiator shop or a replacement is the answer. I'm trying to find a camera or something I can use to look into the radiator from the upper hose location.
68 Roadster 1600
70 Boss 302
65 K-Code Fastback
69 Mach 1 393 Stroker 5 spd
63.5 Galaxy Conv. 427 Dual Carb, 4 spd
72 Ranchero
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ct06033
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Re: Overheating issues 1600

Post by ct06033 »

bossbob wrote: Tue May 28, 2019 12:31 pm CT, what is the follow up on your heating issue, is it resolved, what did you do.

I have a similar situation with my 1600. Stock radiator, car hadn't run in who know's how many years. Got it running last summer and it was running cool mid range on the temp gauge, now it's up to the top of the gauge. I put my temp gun on it, and at the water neck it's around 240 which is also where the temp sending unit is, which seams to match the gauge. Along the head it's around 175. Top hose going into the radiator 175, as I move across the radiator it gets cooler by the time I get to the bottom of the radiator it's at 85. Bypass hoses are hot can't remember the temps. Lower hose is cool to the touch.

I'm thinking that after it sat for such a long time, and now that I have it running, whatever scale might have been in the block is now in the radiator and blocking the flow. Unfortunately, I haven't found a way to really look into the radiator itself yet to verify any clogging. I have burped it a gazillion times and tried every which way to be sure there are no air pockets in the system.

Good news, I guess, is that I rebuilt the rear brake cylinders and my brakes are working again.
So, in the end, it was air in the system. I definitely need to replace my temp sender as well.

The method I used to solve this was taking the caps off the thermostat tower and the radiator, making sure the overflow had a decent amount of fluid in it. then I jacked the car up from the front cross member almost as high as it will go, filled to the top of the thermostat tower, replaced that cap, then continued filling through the radiator until it was full and replacing that cap. Lowering the car, topping off and giving the thermostat to radiator hose a few squeezes. Youll hear some bubbling in the overflow tank as the air in the line gets pushed out and filled with fluid. for those of you who do not have a cap on the radiator, raising the rear of the car might also work to help fill through the thermostat.

This solved my overheating issues at least until it all evaporated out (im assuming through my head gasket) which is another (known for my car) issue all together.

I also replaced my thermostat with a 160F model. Seems to run pretty solidly at 180F which also probably indicates my head gasket issue...
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bossbob
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Re: Overheating issues 1600

Post by bossbob »

ct06033 wrote: Thu Dec 05, 2019 3:24 pm
bossbob wrote: Tue May 28, 2019 12:31 pm CT, what is the follow up on your heating issue, is it resolved, what did you do.

I have a similar situation with my 1600. Stock radiator, car hadn't run in who know's how many years. Got it running last summer and it was running cool mid range on the temp gauge, now it's up to the top of the gauge. I put my temp gun on it, and at the water neck it's around 240 which is also where the temp sending unit is, which seams to match the gauge. Along the head it's around 175. Top hose going into the radiator 175, as I move across the radiator it gets cooler by the time I get to the bottom of the radiator it's at 85. Bypass hoses are hot can't remember the temps. Lower hose is cool to the touch.

I'm thinking that after it sat for such a long time, and now that I have it running, whatever scale might have been in the block is now in the radiator and blocking the flow. Unfortunately, I haven't found a way to really look into the radiator itself yet to verify any clogging. I have burped it a gazillion times and tried every which way to be sure there are no air pockets in the system.

Good news, I guess, is that I rebuilt the rear brake cylinders and my brakes are working again.
So, in the end, it was air in the system. I definitely need to replace my temp sender as well.

The method I used to solve this was taking the caps off the thermostat tower and the radiator, making sure the overflow had a decent amount of fluid in it. then I jacked the car up from the front cross member almost as high as it will go, filled to the top of the thermostat tower, replaced that cap, then continued filling through the radiator until it was full and replacing that cap. Lowering the car, topping off and giving the thermostat to radiator hose a few squeezes. Youll hear some bubbling in the overflow tank as the air in the line gets pushed out and filled with fluid. for those of you who do not have a cap on the radiator, raising the rear of the car might also work to help fill through the thermostat.

This solved my overheating issues at least until it all evaporated out (im assuming through my head gasket) which is another (known for my car) issue all together.

I also replaced my thermostat with a 160F model. Seems to run pretty solidly at 180F which also probably indicates my head gasket issue...
I did all that too, ended up driving it up and down the street, seems to have blown the air pockets out and it is staying cool now. Then I made the mistake of running a compression test, and now have to remove the head to see what's going on.
68 Roadster 1600
70 Boss 302
65 K-Code Fastback
69 Mach 1 393 Stroker 5 spd
63.5 Galaxy Conv. 427 Dual Carb, 4 spd
72 Ranchero
65 GT Coupe
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