Hola Bricksters:

The A/C technician diagnosed a small leak in the heater core (vapor in the A/C vents coming out into the car). Could it also be the heater control valve? It is plastic and seems to be something that will go out.

If not, do I just pour some "Leak-Stop" into the radiator, turn on the heater and wait till the leak is plugged? sounds too simple, but it may work??? I hope so.

Thanks for any suggestions. Genaro.

Hola, amigo: does this vapor come out of the A/C vents when you have the A/C on? If YES, this is normal, I believe, when there is high heat AND humidity and you turn on the A/C. I ask, because it's JULY, and if you are in FLORIDA, I assume you are NOT using your HEAT, correct? Please let us know! ---PD

The othjer answrer is just to splice the two hose going to the heater core and not have any heat. I seem to remember you live in Florida?

Bill D.

I would replace the heater core, but be sure the core is bad before you replace it. If you have a heater hose connection leaking at the firewall. The coolant can run inside the car alongside the tube to the heater core and soaked the carpet. You cannot see it from the engine side without very careful inspection. I had one do just exactly that. Hopefully you don't have a bad heater core. The stop leak might work, but it is not a permanent fix, just a temporary patch job.

>The stop leak might work, but it is not a permanent fix, just a temporary patch job.

Try Bars Stop Leak, the small bottle. I've got 20,000 miles on a head gasket leak on my International Diesel in my Ford Van using Bars.

Thanks Guys:

I live in the southermost city in Texas(= Brownsville) so HEAT and HUMIDITY are with us 10 months of the year. It is equivalent to the winters I spent in Ithaca,New York, with heat replacing cold.

As for the heater core deal, I have had a mysterious loss of coolant for the past 6 months on the 740. I suspect the heater core now. But the heater valve should not be allowing any water to enter the core as long as the A/C

is on, correct??

Perhaps I'll do like on my 240 and install a cut-off valve in the intake line to the heater core. (Cost $3.00 at Manic Boys Auto parts).

Anyway, the auxiliary electric fan I installed is too loud for my daughter.

She'd rather drive with the windows open and not put up with the "747" takeoff sound.

Sigh....no one appreciates when a guy is just trying to help.

Muchas gracias, Genaro.