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| | | | Joined: Jul 2015 Posts: 135 'Bolter | | 'Bolter Joined: Jul 2015 Posts: 135 | I pressure tested my radiator (re-cored @ 25 years ago according to PO). First test was at 6 psi and had no leaks. So I bumped it up to 10 psi and discovered 2 leaks about 8 inches up from the bottom tank.
I brought it to the local radiator shop for repair and their pressure test at 4-7 psi did not show any leaks.
He said the flow was good also and I could probably get several more years of service out of it.
Is 10 psi too much for a proper test on a 1950 radiator?
Jackie
Last edited by JackieC; 08/13/2016 5:11 PM.
| | | | | Joined: Feb 2004 Posts: 29,760 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,760 | That's approaching the point of a blowup. Those old cores were not designed for high pressure and you're courting disaster with over 7 PSI or so. If you want a little leak insurance, run plain water in the radiator with a few ounces of Sodium Silicate (water glass) in it for several heat cycles. When I drove the fire truck with the big 502 GMC engine to KC last year for Ed Pruss, I sealed a minor head gasket leak with water glass. He told me recently that it's still holding, even after driving it on to Denver and adding antifreeze to it. I believe that system has a 4 or maybe a 7 pound pressure relief built into the top tank of the radiator.
That was a really interesting trip!
Jerry
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| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 |
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Jul 2015 Posts: 135 'Bolter | | 'Bolter Joined: Jul 2015 Posts: 135 | The radiator shop found no leaks even after my 10 psi challenge, what is the likelihood that I damaged something?
Jackie | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | if it's not leaking, it's not damaged, just stick to the normal 4-7# cap and get on with driving it til something breaks  Bill | | |
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