I have a friend who wants me to do a tune up and maintenance on her 300E, and I have NEVER worked on a gas MB, so I went to phil's ordered up a good set of tune up paraphenalia (*SP?) and am getting ready to start next weekend,
I just wanted to know if there is anything particular I should look out for?
Crazy girl has NEVER changed her oil (although it leaks pretty bad, so it almost always has fresh oil, but filter never been changed!@*#*($#)) ) her Distributer cap has been cracked for years, and it is difficult to start due to condensation in the cap... so of course I ordered full set of DC parts and plugs. I think I will skip the wireset. 102 for the CHEAP set of wires. I am getting two mahle Oil filters one for now and one for 1000 or so miles later.
looking for any specific or recommended points to inspect on this during tune up.
thanks,
John

Use the correct h9dc bosch spark plugs. They are a non resistor plug. Use of a resistor plug will break down the wires, cap, rotor, and coil in short order, especially one as described. The plug wires likely will be very difficult to remove too, in extreme cases it has taken 2 screwdrivers prying opposite one another pulling the connector out of the recess. Go in with a good pair of boot pullers and resort to the prying method once the rubber cover starts to tear. Cracking the insulator is soon to follow tearing the rubber, so quit there and pry.

Good luck gettin the wires off in once piece, better budget a set of new ones along with the plugs. I did this on my chum's 300E and we ended up having to chisel down the ceramic on the plugs to get to the head of the plug. His haven't been changed easily within 10 years. Cap and rotor are a must for the M103 to run well.

Aside from that, run a can of Seafoam through the top end. Consider changing the fuel filter too. Maybe pick up an air filter while you're at it, flush the PS then toss a new filter in there too.

Eye the fan belt and the fan clutch.

Maybe she'll cook ya dinner and more...

__________________
I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]

iceberg if this is a 10+ year old car that has never had any maintenance.

I went through a similar drill with a 1990 300SE.

The ignition on the M103 might need everything if it has never been maintained:

-rotor and cap, especially if the timing chain cover has leaked (and it does) which leads to an oily distributor cap, also the suppressor housings break down with heat and often crack when you remove them. Fixing the leak is documented in the wiki but takes time and patience.

-as noted, the plug wires will likely be fused to the plugs. Anticipate needing to cut them to remove and of course that means new wires. If you replace wires, getting them in the plastic cover is a pain and your back will ache from leaning over to work on it.

If there is oil leaking from the cam cover, you'll need to replace the gasket.

Transmission cooling hoses often develop leaks - easy to change but messy.

If you replace the serpentine ('poly V') belt, there is a possibility that the belt tensioner will be on its last legs and break leaving you with the prospect of replacing it before you can tension the belt. This is almost as much work as replacing the water pump. Mine was fine but others will tell you of problems.

I guess I'm suggesting that you be aware that cascading repairs often result from what looks to be a simple tune-up on a car that has lots of deferred maintenance and indifferent treatment.

The good news is that parts are very reasonable, both here at Fastlane or at other web vendors.

Also you should do a transmission / Torque Converter drain and re-fill . You will need a Transmission Kit. Coolant drain and re-fill with MB Coolant or Zerex G-05. Drain and Re-fill Differential.

Steve

Dist cap is not so easy to replace.

Read about here
http://www.peachparts.com/Wikka/M103TimingCoverReseal

__________________
Kent Christensen
Albuquerque
'07 GL320CDI, '10 CL550. '01 Porsche Boxster
Two BMW motorcycles

everyone is right about wires, cap etc, also if there is anyoil in the cap the seal is shot, and read the book about the tensioner as you can mess it up easy, was it overheating or just leaking?