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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?

Mike

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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.

Sincerely,

Bill