Carb cleaner down the prechambers? - PeachParts Mercedes-Benz Forum

bipolardave · #1 08-19-2011, 06:40 PM

Just a thought...

I've removed my fuel injectors and shipped the off to be cleaned and tested.

I peered down into the prechambers and saw what looked like "rosebuds" in each one, which I assume to the all important ball that helps to disperse the atomized fuel.

Anyway, I also saw lots of gray which I assume to be carbon build up.

Would there be any harm in buying a few cans of carb cleaner and spraying them into the prechambers?

At worst I figure that I'll wash out some soot that'll flow down the pistons and be blown out the exhaust valves when I fire it up.

It'll take at least a week to get the injectors back, so that should be plenty of time for it to evaporate.

Yes, no, maybe?

engatwork · #2 08-19-2011, 06:49 PM

Personally I would not do it on any of my vehicles. I would not want that crap/crud sitting on the pistons nor getting on the cylinder walls for any length of time.

SD Blue · #3 08-19-2011, 08:45 PM

If it's carbon, I sincerely doubt that carb cleaner would do much anyway. Carb cleaner is literally "varnish remover" and that is not an issue with diesel engines.

A better method would be using Diesel Purge, or similar, after you reinstall the injectors and get things running again.

okto · #4 08-19-2011, 09:34 PM

Quote:

Originally Posted by bipolardave

At worst I figure that I'll wash out some soot that'll flow down the pistons and be blown out the exhaust valves when I fire it up.

Well, true worst would be that it hangs out in the cylinders and your engine runs away when you fire it up. I'm sure it's somewhat irrational, but the idea of spraying anything flammable/explosive into a diesel engine scares me. Too many runaway diesel videos on YouTube...

layback40 · #5 08-19-2011, 11:12 PM

An Italian tune will do a much better job of removing carbon deposits from where its important than carb cleaner.

vstech · #6 08-19-2011, 11:17 PM

I've successfully used PB blaster on the carbon in the PC's during Injector swaps etc. works great! blow it out by cranking over the motor PRIOR to installing the heat shields!

Diesel911 · #7 08-20-2011, 12:48 AM

I have dumped Marvel Mystery Oil into the Cylinders through the Glow Plug Holes of the Volvo and Mercedes (and let it soak) with no ill effects.
I did nothing to help the Mercedes but it freed something up in the Volvo because it stopped putting out the Hazy Gray Smoke that it had at all Engine speeds.

So I believe that the Marvel Mystery Oil will at least soften Carbon but I also think it takes time.

Back in the 1970s we used Carburetor Dip (this is different from the spray) to remove and soften Carbon; and, it was very effective. (Cannot be used with parts on the Engine/Car.)
Since that time the EPA most likely has caused the formula to be changed.

If left in the cleaner overnight Aluminun will get discolored or even eaten up some.

KarTek · #8 08-20-2011, 07:06 AM

Quote:

Originally Posted by vstech

I've successfully used PB blaster on the carbon in the PC's during Injector swaps etc. works great! blow it out by cranking over the motor PRIOR to installing the heat shields!

Yeah, what he said.

The OM606 has deep wells that fill with greasy oil. I sprayed one out at a time then blew the mess out the top by cranking the engine briefly. It blows the old heat shield right out of the head!

I would not however, spray too much in there (more than a teaspoon full) to minimize the risk of a collision between the piston and the accumulated fluid against the head.

Also, don't wait for an extended glow before cranking the engine lest you blow a fire ball out of the injector hole.

whunter · #9 08-20-2011, 07:40 AM

Quote:

Originally Posted by KarTek

Also, don't wait for an extended glow before cranking the engine lest you blow a fire ball out of the injector hole.

This is why you disconnect the glow plug relay FIRST..

vstech · #10 08-20-2011, 08:00 AM

also...
is carb cleaner flammable? when I worked in a shop in the early 80's we used it all the time... IIRC, spraying it into a running motor stalled the motor...

KarTek · #11 08-20-2011, 08:47 AM

Quote:

Originally Posted by vstech

also...
is carb cleaner flammable? when I worked in a shop in the early 80's we used it all the time... IIRC, spraying it into a running motor stalled the motor...

Dang, are you kidding? I use it for starting fluid in a pinch! (Lawn mower

)

pmckechnie · #12 08-20-2011, 08:53 AM

Carb cleaner IS combustable. When we have a no start engine we spray carb cleaner in the intake and try to start. If it fires for a second or two, then we know we have a fuel problem. We have actually driven cars in the shop by walking beside the car, spraying carb cleaner in the air intake and someone else drives the car. However we don't use it around diesels so I don't know what happens with them.

Paul

winmutt · #13 08-20-2011, 09:27 AM

Quote:

Originally Posted by SD Blue

A better method would be using Diesel Purge

What do you think DP is?

whunter · #14 08-20-2011, 09:55 AM

Lubro Moly - Diesel Purge
http://www.worldpac.com/tagged/DieselPurgeLM2005.pdf

Are Diesel additives ,70-90% diesel to start with ?
http://www.peachparts.com/shopforum/showthread.php?t=263157

winmutt · #15 08-20-2011, 11:52 AM

Precisely my point. 73% diesel 15% cetane additive and the rest is gas/petroleum distillants.

Carb/breake cleaner will eat aluminum, probably not the best thing with aluminum alloy pistons?