240D Ping when first started
 

There is a slight ping when I start my 81 240D after it has been setting for 8 hours. After about 5 mins the ping goes a way.

I know that I need to replace the glow plug relay,because sometimes it doesn't work at all. I wait tell I hear the "click" to start the car. Sometimes the relay will turn on and right off, so I only start the car after one cycle is over.

What a diesel purge do anything to help the ping or could be the relay not giving any power to one or more glow plugs?

How do you do a diesel purge?

Its normal. That is the detonation of fuel your hearing, the excess pinging is caused by a cold engine.

Thanks for the info. One last question. What controls the glow plug light on the dash. Does the relay control this?

The relay and a temp sender in the engine control the light. Having your injectors checked for spray pattern would not hurt, and could give you a bit more power. Nailing is often caused by a poor spray from old injectors.

Agreed
 

My experience is DP stops nailing when it's actually being burned but doesn't make it go away long term. Good spray pattern and pop pressure fixes it.

That has been my experience too.

What is the cost to replace the injectors? Or can they be cleaned? Would a purge help any?

I have very good news for you......

I took an injector from my 1977 240D apart last Saturday.

You need a 27mm deep socket (Mine a Craftsman) to remove the Injector and the torque is high so I have a 2 ft piece of pipe to extend my ratchet handle.

I simply put the removed injector in a vice, opened it up, and there are just about five parts in a serial assembly. The pintle is on bottom.

I used a bath of solvent (degreaser) and voila....

When it went back together it was perfect.

This is a very easy task and anyone can do it.

Make sure the shim is put back on top of spring the way it came out.

I was expecting something way more complex and difficult based on narrative on various groups. I see no need to take it to a shop but I am sure it does not hurt. You can see that it is clean by visual inspection. I do not have a cleaning kit.

Go for it and let me know how you are doing.....

I might give this a try. What about doing a purge?

A purge is like using liquid plumber versus a power snake.

I never got a fix out of a bottle other than Whisky!!!!!

Use a purge to keep a system running great....not to fix a system.

Please let me know how you did....