I have a like new 84 300sd with 90K and "Eric-son"(mercedes mechanic) says that it's not nessessary to adjust them that often(15K) unless the car has overheated or been driven hard at high RPM.

It's a good idea to check them at least every other year.

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[/SIGPIC]~cirrusman

1983 Mercedes Benz 300SD - Wife calls him "Chitty Chitty Bang Bang"
[SIGPIC]




1983 Toyota Tercel (Tommy, The little Toyota that could)
1965 Ford F100 (Grandma Ford)
2005 Toyota Sienna (Elsa, Wife's ride)


Gone:
1988 Toyota Pickup
2004 Subaru Outback

1987 Cadillac Fleetwood Brougham
1986 Volvo 740 GL Station Wagon - Piece of junk.
1981 Volvo 242 DL 2 Door - Hated to see it go. R.I.P.
1987 Pontiac Fiero GT

If you find that at 15k they are all within spec, then you may be able to extend a little. If you find they are a long way out of adjustment at say 20k, you may wish to adjust more often.
If they go too long without adjustment, the car will not start when cold as the valves will be leaking. I generally set mine whenever there is the very first sign of the motor appearing to be getting hard to start. It has worked for me for a long time !!

__________________
Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

The probability that all valves will be on spec after 15k miles is very close to zero. And sometimes I wonder if the same isn't true after 15 minutes!!!