Select a Vehicle

Find parts for your specific vehicle

Choose your Vehicle

Having trouble finding a specific product?

1978 Mark V Issues

Hello Bill,
I have a 78 Lincoln Mark V with a trunk leak. The leak appears to be coming from the topside upper left but I just can’t seem to pinpoint the leak. My Uncle said it was the left drain plug but I replaced that and it did no good. I also tried caulking the left side window. The trunk seal seems to be in great shape. Someone told me to climb in the trunk with a flashlight to find the leak but that was useless as well. My Dad also mentioned some drain tube on the older models but I don’t know where to look for this. Any suggestions would be great.
Also my “Miles to Empty” digital reader is working intermittently. Is this difficult to replace? Where would I track this part down and can I repair myself?
Finally where can I locate a cheap factory manual for the car or where is the cheapest source. I love my new Lincoln and want to take good care of her.
Oh and one other question. I bought this Lincoln with 116K miles. Should there be any necessary routine maintenance I should perform at this stage?
Thanks man and have a great one.
Hi Justin,
Tracing water leaks on cars can be time consuming and disappointing at times. Water can enter a car at one point and show up several feet away. Some leaks show up only after the car wash and others only appear after a light but steady rain. The best way to diagnose is to apply water to the suspected area from the bottom and working up. A popular and possible leak on your car could be at the rear window area. To trace a leak in this area, water can be applied to the rear window (lightly) with the trunk open. Excess water will drain out at the trunk gutters during this test as designed while someone in the trunk watches for the leak to appear inside the trunk. This whole procedure requires patience. This is why many owners take their cars to a body shop for this problem.
The Miles to Empty modules are not repairable apparently. We have used ones available, but have found that they can be unreliable in many cases. Furthermore – the problem may be in other items – such as the Fuel Sending Unit itself. In the future we may have a good but fix for this problem but at this moment we cannot offer you anything that would be acceptable to you, or us. I hope you appreciate our honesty in this matter.
We only recommend and sell the proper FoMoCo manuals for your car. We find that anything less does not measure up to our standards. These of course are not the cheapest, but the money spent can easily be recovered during the first repair in many cases. The necessary maintenance schedules are show in the Shop Manuals and the Owners manuals. Please contact us further for any manuals or parts that you may require.

Have a Question? Submit your question to Bill!

Submit Your Question

Your Selected Vehicle