Radiator Coolant Flow
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Radiator Coolant Flow
Is there any way to measure the coolant flow through a radiator? If an engine is overheating and after trying to eliminate other possibilities I suspect the rad is at fault, is there a way to prove it without replacing it?
- brianp87
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Re: Radiator Coolant Flow
not really the only partial way i look is with a temp gun and half heartily try to find a restriction.
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Re: Radiator Coolant Flow
a clear section of rad hose helps. Don't get caught by the water pump impeller seperating from the shaft and not pumping as a result
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Re: Radiator Coolant Flow
Most radiator shops (like me), if you can find one anymore have flow test machines. I dont typically charge shops for this simple test if they buy radiators from me. Jerry.
- ricmorin
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Re: Radiator Coolant Flow
The few I found were identified using the temp gun. Once I had the radiator out, I'd pour water in one side and gravity would hardly get it out the other. That was my confirmation. Not very scientific, but effective. 

Ric Morin - Volunteer Forum Moderator, Shop Owner, ASE Master L1
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- Rich
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Re: Radiator Coolant Flow
Know anyone on a local fire department? Call them and see if they will happen to stop by with an Engine. Tell them you heard about something called a "thermal imaging camera". Then kinda hint like "hey I got an idea! Lets go look at this radiator" You will be able to see it with that!
If you were in "my parts" i'd do it for you.
http://www.marylandenergyauditor.com/ho ... al-imaging

If you were in "my parts" i'd do it for you.
http://www.marylandenergyauditor.com/ho ... al-imaging
Rich Hays
Work 9-11 or 616-696-0020
Being able to get CAPE off a Skew T chart is important in this hobby.
Work 9-11 or 616-696-0020
Being able to get CAPE off a Skew T chart is important in this hobby.
- brianp87
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Re: Radiator Coolant Flow
To me its kinda like a process of elimination. Fan or fan clutch works ok. t stat works ok. is outlet temp on rad different then inlet? Also a must is the combustion gas test. Overheating vehicle are sometimes the hardes to figure out.
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Re: Radiator Coolant Flow
Flow Test Machine. What does that consist of.JBUTITTA wrote:Most radiator shops (like me), if you can find one anymore have flow test machines. I dont typically charge shops for this simple test if they buy radiators from me. Jerry.
Don't laugh, I am revealing my ignorance, I know.
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Re: Radiator Coolant Flow
Im not compruter savy enough to post a pix, but if you go to barbeecompany.com/catalog.pdf and on page 2 they have their RATE-O-FLOW machine. Basically it is a high volume pump with a gallon per minute meter. As a rule of thumb, a 20 in wide radiator with 1 row of 1in tubes(alluminum) , or 2 row 1 1/4 in thick core (copper/brass), should flow approx 20gpm. jerry
- ricmorin
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Re: Radiator Coolant Flow
The radiator shops I've visited had big scary machines like this.
Ric Morin - Volunteer Forum Moderator, Shop Owner, ASE Master L1
Motorcar Alternatives, LLC
603-622-6434 x203
www.motorcaralternatives.com
I find my life is a lot easier when I use Special Orders
Motorcar Alternatives, LLC
603-622-6434 x203
www.motorcaralternatives.com
I find my life is a lot easier when I use Special Orders
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Re: Radiator Coolant Flow
Ric, that would be a boilout tank for cleaning. Hot caustic soda is pretty nasty stuff, but works great on copper/brass radiators. Just dont try to clean aluminum radiators with it. 

- steven kiser
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Re: Radiator Coolant Flow
A bit old school here but the way i test for a restriction is letting it run until the temp reads about 1/3 and running my hand across the radiator. I can feel the cold spots this way. I haven't run into a restricted radiator in years. The more i think about it i've run into impeller issues more than restricted radiators.
never argue with a fool, they'll drag you down to their level and beat you with experience