Manager Forum

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?

not really the only partial way i look is with a temp gun and half heartily try to find a restriction.

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

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.

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.

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

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.

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.

Flow Test Machine. What does that consist of.

Don't laugh, I am revealing my ignorance, I know.

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

The radiator shops I've visited had big scary machines like this.

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.

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.