Hello everyone,

I need some help doing valve adjustments on an 84 300D Turbo. I've read dieselgiant pictorial and a lot here in this forum, but nothing is helping.

I have 3 stubborn exhaust valves that I can't loosen to fit a .305mm feeler through it. A .102mm fits, and I can get that stuck and I can also make it loose, but I can't get it loose enough to make a .305mm feeler fit.

I am using the top to adjust the height and the bottom nut to loosen/tighten. I did notice that when I keep the top nut still and loosen the bottom, the valve spring moves. Is it supposed to? or is it supposed to be stationary when loosening/tightening? I've been turning it a lot and the gap stays the same. If it's supposed to stay still, how do you keep if from moving without using a wrench (I don't have one large enough). I've heard of using a screwdriver, but I don't understand how that works.

Thanks in advanced!!

The OM61X series engines are readily adjustable using factory wrenches that are designed not only for the correct sizing but with a 'just-right' offset to clear valvetrain components. I've never even attempted a valve adjustment without the wrench set. It may be tough otherwise to break-loose a few of the adjustment nuts. As for the turning of the valve spring, that's where having the big wrench of the wrench set comes into play. Phil, with Fastlane, can order the wrenches for you.

thanks for the reply Adenauer...

I do have 14mm wrenches, but not the large 30mm one.

So just so I understand, if both nuts and spring are turning when loosening or tightening, then the valve stays still, meaning it's not going up or down. correct?? Also, that means that if the valve spring is turning, then again, the whole valve is turning and is not moving up nor down. correct?

I'll check out fastlane for the wrench, BUT.....

Does anyone know how I can keep the valve still without purchasing the wrench?? My car has not been driven for 3 weeks, and I only have time to work on it on weekends. I kinda want to be done today

Thanks again.

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1984 300D Turbo -- Just bought it June 2007 for only $650. My first Mercedes-Benz and my first Diesel.
1964 VW Karmann Ghia -- in parts Long overdue for a restore.
2006 Audi A3 -- Great car, but I hate the car payments!!

Use a large screwdriver wedged against the side of the valve spring retainer so that it cannot rotate. The retainer is indexed to the valve stem; if it cannot rotate, neither can the valve.

many here have bent their own wrenches...

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Cheers,
Robert

Hey Tangofox I did it!!!

Engine starts so much quicker and runs a lot smoother.

Thanks!!!

I read in previous post to use a large screwdriver as well, but I wedged it between the spring coils. Obviously that didn't work. And for some reason when you posted to wedge a large screwdriver, I looked at it again, and I wedged it against the other spring retainer adjacent to the valve I was working on. I also did one that wedged against the rocker arm tower thingy (excuse me, im a noob,haha) and that worked as well.

This always happens to me, whenever I have a problem, I ask someone, then miraculously I figure it out. Anyway, It took me about 6 hours, but well worth it. I'm glad I don't have to do this for a while.

Thanks again!!

__________________
1984 300D Turbo -- Just bought it June 2007 for only $650. My first Mercedes-Benz and my first Diesel.
1964 VW Karmann Ghia -- in parts Long overdue for a restore.
2006 Audi A3 -- Great car, but I hate the car payments!!

i had my wife hold the large spring nut with some gas pliers while i adjusted the valve... worked pretty good but having the correct bent wrenches would have made it much easier