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1970 Mark Blower Motor And Relay Issues

Bill -

I have the dome top blower motor that's not available. I took 2 motors and made one with old housing. Its been working but Window safety relay is bad now. Measured amp draw with blower on. It has 20 amps draw. I suspect with hood closed ac on and driving for 1 hr it must be getting over 25 or 30 AMPS. I replaced window safety relay over 1 yr ago. Now it is bad again. Thoughts on how I can get a new or rebuilt blower motor? And if I am on the right track?



Hi Mike -

Welcome to Bill's corner. If you suspect and have proven that the blower is drawing excess amps, this blower motor must be replaced with a good one that is within specs.

Finding one to fit your Housing is the issue - they are not remanufactured at this time. We have also not found anyone who can successfully rebuild them to date.

I would suggest that you retest this blower for excess draw using the following method. Hook up a battery charger under the hood to the battery on a low to medium charge. Run a heavy gauge jumper wire from the battery positive post through an ammeter and a 30 amp fused wire that feeds the blower. The blower should then operate on high speed. The engine is not running and you can leave the blower running for a long period of time ( at least an hour ) to heat up the whole blower without discharging the battery. Recheck the amperage draw of the blower at this time. The draw should be 17-23 amps. I personally use am Amp meter with a range of 0-50. If it is close to or higher than the 23 amps , this draw could have aggravated that high range relay internally and caused it to fail. This relay and wire plug in should be located under a lip of the right front fender with the hood open.

If the blower is within specs, please send this relay (that you report has failed again) to us for reinspection.