I have a 76 300D (115 114) that is tough to start, especially when warm. I have a manual for the W123 series diesel (Haynes)but some of the stuff looks different than my engine. Can someone give me some tips on the proper way to set the start of fuel delivery for the engine in my car.

Thanks,
John

John,
I doubt if your injection pump is out of time,unless the timing chain has jumped by more than one link. I have seen them start and run 18 degrees off. That's one chain link. If it's off by two links, the pistons will hit the valves.
Let me suggest you do a valve clearance adjustemt. Improper valve clearance will make a diesel hard to start.
Make sure you have pure diesel fuel in the tank. A mix of diesel/gas will make a diesel hard to start. Too much gas in the mix. and a diesel won't start.
The next thing to do is to do a compression test. Your car is 25 years old, so maybe its age is begining to show.
Keep us posted on you progress.
Bill Lewallen Lexington,Ky. Home of LexMark Printers

Greetings,

There could possibly be a few things preventing your car from starting right off when the engine is already warm. First thing that comes to mind, is as Bill said, tired and most likely losing compression. Once the oil has warmed up to operating temperature it is more likely upon cranking the engine to pass by the rings causing a decrease in compression until it's actually running again. The other problem you may find, probable but most likely not the cause, is your check valve on your primer pump is sticking open allowing fuel to drain out of the line making you lose your prime on the injection pump. You'd be able to see air in the clear return lines if someone else was cranking on the starter while your head was under the hood. Wild stab, but have seen it happen on an overly used and old primer pump. They're cheap to replace if that is the problem. I think part shop has them for around $14.00

Charles

I adjusted the valves on Sunday. It made some difference in the ease of starting when warm. Still not perfect, but enough of an improvement to convince my wife that she can get it going when she takes it out.

Thanks for the help.

John

John,
Have you tried letting the glow plugs stay on a little longer. When the glow plug indicator light goes out, the glow plugs are not turned off right then. They (glow plugs) will stay on for quite a while after the light goes. Check this by connecting a volt meter to one of the glow plugs, and see when the voltage drops back to zero. If you don't have a volt meter, after the light goes out, be real quite and you will hear the glow plug relay click off. Have patience. You may be suprised at how long the glow plugs are actually on.
Bill Lewallen Lexington,Ky. Where diesels purr and turbos whirr..

Greetings,

As Bill mentioned the glow relay on your car probably stays on even after the light goes out, generally another 45 seconds or so then you'll hear it click off. You can either count to 20 after the light goes off and give her a crank and the prechamber should be quite warm. I noticed that Bosch also makes a quick timer for glow plugs as well, that stays on for 3 minutes after the light goes off. Just wondering if they have one that dates back to my '80 serial numbered engine. Last time I looked it wouldn't, so maybe someone out there could help us out on this one.

Charles

I tried letting the glow plugs warm the engine after the light went off, with positive results. Car starts first time, every time. Between the valve adjustment and this little tip, the wife is very happy with her car. Acceptable pickup, starts easier.

Thanks for the advice.

John