Simple questions from a simple mind
 

Question #1- My ac in my 85 300 sd does not work as well as it should. I would like to check the insulation on the line behind the glove box. How do you remove the glove box without destroying the little plastic gizmoes that hold it in place?
Question #2- Where can I find a diagram laying out the routing of all the different vacum hoses, fittings and little valves and such? Everything seems to work just fine, but a lot of the vacum lines are old and brittle, and I would love to replace them, but would dearly love to know what each one does before I do. Anything like a wiring diagram available anywhere?

Simple mind? Charlie Burchill or Jim Kerr? :)

1) http://business.baylor.edu/Richard_Easley//autofaqs/recirc.htm

To remove the glove box, pry up on the inner circle of the clip. Something that looks like a fat nail will emerge. With the fat nail out, pry up on the outer circle. Something that looks like a drywall anchor will emerge. Pull down on the courtesy light and shove it back through the hole. Pull the glove box liner.

2) There should be a decal over the right headlight with a vacuum diagram. Otherwise it's time to invest in a proper shop manual. The Haynes manual for the 300D is pretty good IMO but the factory manuals are difficult to be without.

Sixto
95 S420
87 300SDL

I would suggest that you check the condensor (the 'radiator' in front of the radiator) for dirt and 'stuff' and give it a good spray cleaning to be certain that air flow is not blocked. If it's significantly blocked, you might be noticing your temperature gauge showing a bit hotter in normal driving too.

I would also suggest to check that the electric fan(s) work as they should.

Insufficient airflow through the condensor will result in 'not enough cooling' whether from slow driving, where the electric fans cannot keep up with the demand, or airflow blockage.

It is not likely that the insulation on coolant lines is causing you to lose cooling capacity, since the lines have a relatively small surface area. The insulation prevents condensation and water drips in the dashboard and cabin.

You could be low on A/C refrigerant. This can be checked by a technician.

Best regards,

Jim