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1969 Mark III Questions

Bill -

My Mark III will not change from defrost, to heat, to dash vents, and I cannot turn heat off. Also noticed the rear vents will not operate. Can you give me some direction and what parts I should check for proper operation, and do you have these parts? Do you have a repair manual for my car? I would love to visit sometime!




Hi Marv -

Very nice car and welcome to the Lincoln Land blog. We certainly would be pleased if you could visit our showroom and warehouse in Clearwater. You would be able to meet us and to see some very nice Lincolns and FORD literature that we have for sale and on display for fellow Lincoln lovers.

The description of your a/c problem sounds 99% like a classic loss of vacuum to the Climate Control and the Flo Thru rear vent systems. Loss of vacuum will cause the system to drive and default to full defrost and max. heat with the fan at high speed. The rear vent will also become inoperative at the same time. The Shop Manual set is very explicit on these complicated systems and is an absolute must in order to quickly diagnose the vacuum and electric features of all 1969 FoMoCo vehicles. If you wish, we can arrange to have a set sent to your address. I hope that the above helps and if you need any further advice or any parts to correct your problem please do not hesitate to contact us at any time.