Holy soot build up!!!
 

Yesterday I went to replace the valve cover gasket on my '87 300TD. In taking the air intake crossover pipe off, I discovered that there is a serious build up of soot in the cross-over pipe and the whole intake manifold. I scraped off as much as I could, using my shop vac and a wire brush. Unfortunately I couldn't get to the inside of the intake manifold/plenum (sp). There is a serious build up in there and I imagine the engine would run even better if that were all cleaned out. Has anyone removed the manifold and cleaned it out?

I took the entire intake manifold off as part of a glow plug replacement job. It was also good to replace the intake manifold gasket at the head because it appeared to be leaking.

The best I could do was scrape all I could with a gasket removal scraper, and then use degreaser and a garden hose through the sections I could not reach. I'm sure I got the majority of the buildup out of there.

This is caused by the EGR valve porting exhaust soot into the intake manifold. The intake also gets oily crankcase blowby as it is ported into the intake near the turbo. The combination of soot and oily air creates a sludge buildup. If your EGR would happen to malfunction somehow, then the soot would not be present.....

:)

Ken300D

I heard that!

you will also get less buildup with synthetic oil, as it won't coke like the dino stuff.

Peter

Yeah, the vacuum line for the EGR on my '85 300D became mysteriously plugged up shortly after I aquired it..;)