Removed the intake manifold on my 617.952 and found all the intake passges clogged with a carbon goo with a similar consistency to chewing gum. Not being a diesel mechanic I have never encountered something like this before. Is there any sort of home remedy that can clean this out? I can think of things like a hot tank on a professional level, but I don't know what approach would work at home. I have never seen anything like it.

IMO, just give it to a machine shop to hot tank it.

Or you can let it sit in high purity bio diesel.

__________________
1998 Ford Escort ZX2 5 speed - 279,000 miles My Daily

1992 Mercedes 300D 2.5 202,000 - Pure junk
2000 Mercedes E320 Black - 136,000 miles - Needs repair

Don't forget to grease the screw and threads on the spring compressor.

Yup, hot tanking it is the best/easiest/least messy way to deal with it and you don't have to do any scrubbing. A bath in a 50/50 mix of ammonia and hot water works well but is stinky and messy. Never tried the bio-diesel for clean-up. Might be worth a shot.

__________________
“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.”
― Brian P. Cleary, You Oughta Know By Now

Scrape out what you can, it'll make the job a lot easier. Get a big tub and soak the manifold in a strong concentration of degreaser, it'll soften the crap so it comes out pretty easy with a bottle brush. Wear gloves, it makes a mess. If all else fails, Kerosene works well.

When you're done, disable the EGR system if you want to keep it clean.

__________________
Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Gone and wanting to forget:
1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]

cons/pros to disabling? how would you suggest? plug it up or run it under the car?(rust prevention? )

__________________
1978 300D

regarding disabling the EGR.

Pros, runs cleaner. Better fuel mileage.

Cons, you won't get the privilege of cleaning your intake manifold in another 100k miles.

There is absolutely no reason to keep your EGR functioning. Contact ROLL GUY in this forum for a kit to disable.

$1000 fine if they ever start enforcing diesel emissions. Social responsibility not to pollute. Negligible impact on fuel economy or performance.

Most people don’t even know what egr is. Majority of cars 20 years ago and up don’t have it. I’d be shocked to believe that a cop knows exactly what to look for then cares enough to write paperwork on it. Egr has been nothing but problems and does very little for emissions

__________________
1993 e300
1995 e320
1994 e320
2006 s500 4matic
2004 Jeep wj overland
2001 Ducati 748
2004 Honda shadow aero

ah I meant removing the CCV not the EGR. my non turbo doesn't have EGR. I was looking to route my CCV line under the car or something since I just cleaned my intake after new header/gaskets

__________________
1978 300D

What I've done with this is to buy a big plastic tub from HD. The manifold has to fit entirely inside or you'll make a huge mess for which she'll never forgive you. Wear your oldest, expendable clothes. High cuff chemical resistant gloves, with a pair of thin nitrile gloves underneath. Use a bunch of small paint brushes and disposable cloth rags. The best brushes to use are the cheap ones they sell for applying solder flux, the steel handles do double duty as scrappers. Buy a bag:

https://www.homedepot.com/p/Steel-Core-1-2-in-x-6-1-8-in-Horsehair-Bristle-Shop-Acid-Brushes-144-Piece-75841/308076784

Gasoline is the best solvent, but very dangerous. The advantage is that it's cheap and really cuts the crud. It evaporates quickly, which helps with cleanup. Mineral spirits also works. The good news is that you only have to do this every 150K miles or so.

You won't be able to dump the spent cleaning fluid anywhere, so the best bet is to stick it under the deck until it evaporates. Gloves, clothes, hat, rags, brushes, all bagged and trashed.

a bag of oil soaking dust/dirt can take care of that spent black fuel.

__________________
2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

I went to an engine shop and had them hot tank and media blast it for me.

$35 was money well spent.

__________________
Onus probandi incumbit ei qui dicit, non ei qui negat

I recondition w123/w126/w124/w140/r107/r129/ steering boxes!


1984 300D "Elsa" odo reset 6/2011 147k
1983 300TD "Mitzi" ~268k OM603 powered
1995 E300 "Adelheid" 262k [Sold]

I’ve used a plumbers torch and air compressor at the same time. Cleans it out like a mofo and fast

__________________
1993 e300
1995 e320
1994 e320
2006 s500 4matic
2004 Jeep wj overland
2001 Ducati 748
2004 Honda shadow aero

__________________
“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.”
― Brian P. Cleary, You Oughta Know By Now

2x fire if you’re wanting to DIY

I used one of those trigger operated propane blow torches for weed killing.
Worked very well. Obviously you’re gonna wanna stay up wind

__________________
Current fleet
2006 E320 CDI
1992 300D - 5speed manual swapped

former members
1984 300D "Blues Mobile"

1978 300CD "El Toro"