I have not been able to find an FAQ or Guide for Required Preventive Maintenance for a '77 450SEL V8 Gas.

Just recently purchased a '77 450SEL V8 Gas that has 86K original miles. The car is in great running shape and I would like to keep it that way.

Other than a flakey power lock system, a collapsed lower cushion on the rear seat, and a slight leaking valve cover gasket, I do not see any issues.

Is there a Guide or something that would list everything that I should check and service?

Let me know please.

Boyd

go to vintage section of this site

look for "useful Links"

look for 116.org or similar

on that page is a link to the service manual for your car where all is revealed

Thank you very much.
I found the manuals here: http://handbook.w116.org/

Boyd

Sounds like a great car. I have a 116 and love it. Having recently fixed my vacuum system and all the locks, we can help you with that.

The vacuum diagrams are contained in the handbook and fixing locks has been covered here many times.

Good luck with your car.

Put up some photos. We can't see enough 116s

Boyd,

Biggest thing with the 4.5 is to keep up on 3,000 mile oil changes or else you'll experience premature wear on the right camshaft. Also, 100K miles is a good point to replace the timing chain, tensioner and guide rails.

As for the other mechanicals, stick to this regimen:

Every 3K miles: Oil and filter change
Every 30K miles: Transmission fluid and filter change, air filter change and fuel filter change
Every 15K miles: Spark plug change (use ONLY Bosch Super plugs)
Every year in spring: Flush brake fluid
Every two years: Flush coolant (use Zerex G-05 or MB type)

The rear seat cushion is common on W116s. The horsehair gets old and deteriorates. As for the locks, that's also a typical issue, you've probably got a vac leak in one of the elements in the doors. They have diaphragms in them that tear when they age. Also could be a broken line in a door jamb.

__________________
Regards,
Aaron