All GP or some GP, that is the question. - PeachParts Mercedes-Benz Forum

winmutt · #1 10-30-2006, 03:41 PM

Someone in here suggested doing all if more than one has failed. I think I would like to back this statement up. Tested my GP a few weeks ago, found a few bad ones and replaced them. GP still didnt light up. Turns out another had burnt out. So maybe replacing all at once is not such a bad idea (a bit pricey though at $10 per).

dieseldiehard · #2 10-30-2006, 05:28 PM

Its the burned light syndrome, if one fails in a string of lights chances are great that there is soon to be another die, if they were all put into service at the same time. So the labor to get all the tools out is repeated if you only replaced one GP, also its better to turn the engine over after you use the GP reamer with no GP's in the car. This throws out all the loose crud with a few seconds of cranking. $10 is a good price, think of the labor you are saving by DIY, its greater than the cost of the plugs.

With the 617 engine so easy to get at the GP's its a cake walk compared to the 602, 603 engines where you have to be a masochist to change GP's with the intake manifold in place.

#3 10-30-2006, 05:46 PM

I don't think there is a "correct" answer, it's up to you. On my 616 and 617, I just replace them one at a time as they burn out because it's so easy to do. I don't bother to take off the injector lines, I just squeeze my hand in and get it done in 2 or 3 minutes. If I had a 60x, I would probably do them all at once because it's more work.

Jadavis · #4 10-30-2006, 08:22 PM

Quote:

Originally Posted by Craig

If I had a 60x, I would probably do them all at once because it's more work.

That is where I am right now. Of course I also broke a throttle linkage end piece while I was in there so now I am waiting on that before I can put it all back together. (Intake manifold is out.)

2 of my 6 read completely open. 2 read around 30 ohms. One read .8 ohms and the other read .6 ohms. I put in 6 new, but I am keeping the 2 good ones.

-Jim

dieseldiehard · #5 10-31-2006, 11:40 AM

You removed the manifold I presume? Anyone that can change GP's on the 603 engine without removing the manifold and injection lines is a nutcase as far as I am concerned
BTW you can get metal ends to replace the plastic throttle ends that MB started using in '87

Incidentally, anyone with a E300D (OM606) will have serious GP issues and probably should not attempt removing GP's especially one that is stuck, else the head has to come off

Jadavis · #6 10-31-2006, 12:21 PM

I removed the intake manifold and cross over. Even with them removed it took several combinations of tools to get all of them out.

While I am in there I cleaned all the gunk out of the intake manifold and crossover tube and out of the ports in the head leading to the intake valves.

Tomorrow I'll be installing the injector line heaters. I'm going to run the lines back to the fuse box, but not finish installing them right now. I don't have time. You can't do the heaters with the manifold on so I am doing that part right now. I also removed my ALDA.

Hopefully the rod ends that I ordered from Phil are the metal ones.

-Jim