MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGA - Cooling System Trouble

The specifics regard the '59 Twin Cam but this could apply to any car. After weeks of fighting little leaks after the rebuild of my MGA's cooling system, finally all was fine...till the other day. Dang! Coolant on the garage floor when I got home. Last night I put the Stant pressure tool on the car and pumped it to 20 pounds or so. I found the leak...the outlet elbow of my brand new radiator. Looks like its coming out to be resoldered; a real pig of a job--removal and replacement.

In a complete check of the system with the pressure tool, I checked the cap. It held pressure off the scale!! 35 pounds before it released. Its a relatively new 7 pound cap.

Is this what caused my radiator's outlet elbow to spring a leak?

So--more info: This morning before leaving for work, I pumped the sytem to 7 pounds. Home now for a break and 4.5 hours later, its still at 6.5 pounds.

Would I be foolish to think that just a proper 7 pound cap will stem the tide of coolant leakage?

I'm ready to try an 8 oz jar of liquid aluminium from Bar's Leak. Bar's Leak swears it doesn't clog heater cores. Anyone have a specific opinion on Liquid Aluminium by Bar's Leak? Perhaps it will seal the seepage on the radiator elbow and I'd duck a bullit??

Thanks folks!

Paul
Paul Hanley

Paul

If you had topped up the coolant before going out, then on return and parking, the temp will rise before cooling as the water is no longer circulating and cooling. This leads to a small dump of coolant through the overflow.

Try again without toppiing up, and see if you get the coolant dump again.

If the system pressure is getting too high it will expose the weakest point to release the pressure (in your case the elbow). Changing the cap for one in spec will avoid a repeat of the problem, but won't cure the leak.

Given the propensity of the TC engine to overheat, and the cost of fixing them, I would be inclined to get the rad properly repaired rather than bodge it.
dominic clancy

Paul--My Dodge truck blew out two radiators before I realized the cap was overpressurizing....causing the plastic tank to separtate from the metal core. 35 psi could cause all kinds of failurtes. Bars Leak is good--but it doesn't match a proper repair. If your neck is leaking--good chance theres a split--which can get worse from vibration and heat.
R. L Carleen

I hear ya both loud and clear. A proper repair is valid advise. I'm back on the road now after a dose of Bar's Leak and a proper cap. Put about 75 miles on it today and all is bone dry! Pulling the radiator is a tough job in a Twinkie. Well, replacing it is the real pig so I am avoiding the pain for now but will keep a keen eye on the situation and bite the bullet if necessary. Thanks for the help.

Paul
Paul Hanley

This thread was discussed between 15/04/2006 and 16/04/2006

MG MGA index

This thread is from the archive. The Live MG MGA BBS is active now.