Testing radiator
Thread Starter
Drifting
Joined: Aug 1999
Posts: 1,451
Likes: 84
From: Round Rock TX
Testing radiator
I would like to see if my radiator is in good working order. Any suggestions on how to check when it's outside the car. There isn't a radiator cap on the radiator so can't really seal the hoses off and pressure test it that way.
Team Owner
Joined: Jun 2001
Posts: 23,363
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From: Virginia USA
Pressure test is really the only way. You can make some plugs or just take it to a radiator specialist. I just had mine checked and he did it for free. Found two leaks and he charged $60 to fix.
Team Owner
Joined: Jan 2006
Posts: 37,637
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From: Crossville TN
Pressure is pressure. Get suitable rubber caps/clamps for the hose fittings, put an air pressure fitting in an old radiator cap (and defeat the pressure limit), and use air pressure instead of water. Just be very careful not to raise pressure too much. If the radiator can withstand 18-20 psi, it will be fine for 15 psi cap.
Air will leak a lot easier than water; and you can put it under water to find pinhole leaks.
Air will leak a lot easier than water; and you can put it under water to find pinhole leaks.
Last edited by 7T1vette; Oct 17, 2016 at 07:10 AM.
Burning Brakes
Joined: Oct 2015
Posts: 781
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I agree on taking it to a GOOD radiator shop..They can test it to specs, repair it if necessary, rod & core it if req'd.., put proper cap on and make certain it is right for the reinstall..Tell them what car/engine it goes in..about A/C etc...jim
Le Mans Master
Joined: Jan 2006
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From: Butler Pa
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Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
I'm not sure there are any "auto" radiator repair shops still in existence. You can buy a new radiator for less than an old one can be repaired. These days, you just throw away the one with a problem and install a new one for less than $200.
There are still some truck radiator shops, but they know they can't make any money on auto radiators.
There are still some truck radiator shops, but they know they can't make any money on auto radiators.
Thread Starter
Drifting
Joined: Aug 1999
Posts: 1,451
Likes: 84
From: Round Rock TX
It's the original radiator so really don't want to toss it. Likely will Frankenstein something together with pvc, radiator hose, pressure gauge, and air fitting. I will fill the radiator with water, then throw about 7-12 lbs of air. If it holds the pressure, will call it good.
Will have to see if radiator shop exists if it doesn't hold. Of course, I need to see is there is any scale inside too.
Will have to see if radiator shop exists if it doesn't hold. Of course, I need to see is there is any scale inside too.
Team Owner
Joined: Jun 2001
Posts: 23,363
Likes: 1,059
From: Virginia USA
I'm not sure there are any "auto" radiator repair shops still in existence. You can buy a new radiator for less than an old one can be repaired. These days, you just throw away the one with a problem and install a new one for less than $200.
There are still some truck radiator shops, but they know they can't make any money on auto radiators.
There are still some truck radiator shops, but they know they can't make any money on auto radiators.
Procore of Northern Virginia.
Team Owner
Joined: Jun 2001
Posts: 23,363
Likes: 1,059
From: Virginia USA
Why are you so adamant on filling with water and pressure testing that way. Pressurize it with air, it will only take about 10psi for the test and fill something that the radiator will fit in with water and submerge it in that. It will bubble wherever there is a leak. It would be easy to go to the hardware store and get some hardware to make caps.
Last edited by theandies; Oct 21, 2016 at 04:54 PM.
Race Director
Joined: Oct 2008
Posts: 19,145
Likes: 1,667
From: Long Island
just cap off the inlet and outlet, get 4 really large friends and put them and the radiator in the pool, the bubbles will tell you where the leaks are - AT LEAST SOME OF THE BUBBLES WILL 
Cost = 3 six packs , maybe 4
Cost = 3 six packs , maybe 4
Last edited by BLUE1972; Oct 22, 2016 at 02:07 PM.
Team Owner
Joined: Jan 2006
Posts: 37,637
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From: Crossville TN
Filling the radiator with water will just make it that much harder to spot a leak. Air will bubble; water will ooze...and you may not see it. Pressurize with air to psi you want to guarantee has integrity. Stick it in a pool or tub and watch for air bubbles. That's the way it's done in industry.
Le Mans Master
Joined: Jan 2001
Posts: 6,689
Likes: 1,365
Just get a bicycle tube...
Clamp it onto the inlet and outlets of the radiator. Plug or cap the other connections. Place radiator underwater. pressurize with air. easy.
If you don't have a big enough container to place underwater, then use "Snoop" or equivalent to look for bubbles.
PS- I think those kiddie pools are fairly cheap (but I don't really know?), so perhaps using snoop may be easier. It's easy enough to add more air pressure with the bicycle tube while leak-checking.
If you don't have a big enough container to place underwater, then use "Snoop" or equivalent to look for bubbles.
PS- I think those kiddie pools are fairly cheap (but I don't really know?), so perhaps using snoop may be easier. It's easy enough to add more air pressure with the bicycle tube while leak-checking.
Last edited by carriljc; Oct 23, 2016 at 10:34 AM.
Racer
Joined: Jan 2016
Posts: 289
Likes: 77
put a few drops of dish-washing liquid in rad, fill with water. take an old bicycle hose, cut it open with pair of scissors on opposite side of valve stem. stretch open ends of tube over upper and lower hose ends and clamp. cap off smaller rad nipple with vacuum cap an clamp. put 15-20 psi into radiator through bicycle valve stem. bubbles will show up where it leaks.