617 Head disassembly and EGR crud.
 

I removed the valves from a turbo 617 head and found you really don't need any spring compressors to remove them. The valve springs really don't have much tension on them once you remove the nuts from them. It was one of the easiest head disassemblies I have ever done.
I did find lots of carbon on the intake valves and ports. It was shocking to see what a horrible thing an EGR is to a diesel engine.
The exhaust valves also had a groove worn into the face. It seems that by at least a 170K miles there is damage done to the exhaust valves. I tore into another head with unknown mileage and found more of the same but even more wear on the valves and even more crud in the intake ports. I could imagine over time these engines can get choked to death from the carbon soot in the intakes caused by the EGR.
Another good reason to remove the EGR for "testing" purposes.

I was at Pick N Pull today looking for a thermostat housing and a water
pump housing. had to remove the EGR on two cars 81 SD and 82 300D.
on both of them the hole was plugged solid. can imagine how the rest of
the manifold looked inside.
at 249798 miles we changed my Ca. 85. got rid of the trap and other Ca.
required s#%&. the intake manifold was really packed with carbon sootand oil. I just removed manifolds after 81000 miles, and they are really clean.
just a little oily. amazing how much crap the EGR dumps in there.
also the intakes on the head still have quite a bit inside.
this has to lessen the performance & mpg as these engines are getting
older.
charlie

At the rpm these diesels turn the valve springs don't have to be all that strong. This contributes to long life and reduces friction. It also is something to keep in mind when revving it up high.

Some folks here talk about revving it over the redline. This invites a valve meeting up with a piston.

Thanks for sharing.

Tom W

It makes sense about the "weak" springs. Diesels are usually slow revving engines. It just amazed me how easy it was to remove the valves. I'm used to having to apply lots of pressure to remove the retainers from the valve springs. I was actually prepared to do the same with the 617 head.
The other thing was all the crud in the intakes. I'm wondering about the Italian tune ups our members do. Running the higher mileage engines hard could possibly dislodge the crud into the intakes causing who knows what to the combustion chambers. You certainly don't want to introduce any cleaners directly into the intake as the crud can be easily loosened by solvent oils.

You can install titanium valves and get an engine that will rev higher with the same springs and just a tad more power. Since the OM617 isn't well know for breathing well if you combine them with a reground cam with a more aggressive profile and you have a lot more potential for power and torque. It will cost you $$$ though.:rolleyes:

http://www.delwestusa.com/manufactured/titanium_valves.asp

Right now I'm really just going to look for another running engine.