Well, my car has now been graced with first major service since I got it, consisting of new fast glow plugs and necessary wiring changes that go with that, installation of block heater, new thermostat, and valve adjustment. Results are largely positive- glow time is now only 10 seconds, compared with 45, startups are much more positive, I don't need to use glow plugs at all once engine has been warmed up then shut down for 15 minutes, and idling is much smoother. However, I have also noticed a definate decrease in acceleration. When people say how slow these cars are, it made me wonder, because I thought my accelaration was pretty good, even with automatc starting off in 2nd gear. The car still holds its speed good once up to 65 MPH- I've noticed no change on my favourite test hill- still drops to 60 as before, but getting to 65 seems to take much longer.

By the way, he also changed my oil (5W40), and I have an almost new air filter in the car. Fuel filter has not been checked.

The mechanic found that the valves were too tight on three cylinders, and adjusted them. He also thought my timing chain is OK and overall engine health good. I got a definate improvement in warm starting, which could only have resulted from the valve adjustment, but Is it normal to expect correct valve adjustment to actually result in slower acceleration? Doesn't seem right to me. Should there perhaps be an accompanying adjustment in injection pump timng when valves are adjusted?

This mechanic works as an independant on Mercedes and many other imports, but I don't think he's really well studied up on Diesels. When he first checked out my old series glow plug arrangement, he had no idea what he was dealing with- I had to explain it to him. Once he understood, he did succeed in building up a very effective fast glow system for me using a push button and off the shelf high current relay.

Comments appreciated.

Dave

1976 White 300D W115 "Pearl"