removing carbon buildup

dqdave1 · Dec 18, 2007

How can you remove carbon buildup short of teardown. Glow plugs have carbon buildup and cannot not be removed. Are there any additives or sprays for diesels that can be used to remove carbon. I thought there may be something to spray into intake with air cleaner removed while engine is running to remove carbon.

jjmarotz · Dec 18, 2007

Short of a teardown I have never heard of any sprays or addatives that accomplish this. Excessive carbon buildup is a byproduct of un-burnt fuels. Everytime you see a diesel pickup or big rig belching out black smoke, guess what===that's unburnt fuel. If you think you have too much buildup this could be caused by a faulty or out of whack injector pump or carburator. I commonly, (on my old carbed pickups) will mash the throttle for a short burst with high rpm's to create a higher temp in the combustion chamber and valve train, than normal. The higher heat will burn out most of the excessive "CRAP" out of it, thus making it run better. Newer fuel injected and computer controlled engines don't normally see this problem.

RoyJackson · Dec 19, 2007

Boy, you've either got a lot of hours on that tractor...or a lot of idling time!
I've read that misting water in a gas engine can break up carbon deposits, but never heard of using this method on a diesel.
Have you talked to a diesel mechanic yet? The proper solution will probably be pulling the haed, but you never know until you ask.

BTW, I had to have my Ford Explorer's heads decarbonized a few years back...ain't cheap.

RichNJKubota · Dec 19, 2007

Be careful with that water mist. The water must be in vapor form. Water droplets have been known to crack hot piston rings.

RalphVa · Dec 19, 2007

I've seen my Dad pour water down the carb inlet to decarbonize a gas engine. Not recommended for a diesel.

I'd try using something called Chevron Techron red line. I've used it twice in my 1983 Benz to stop pinging at constant, medium speed. (That's all, just twice in 25 years and 205k miles) Worked both times. The pinging was likely caused by carbon buildup causing hot spots. You put the Techron into the diesel fuel. I'll work in one tankful if it's going to.

Ralph

drtydeed · Dec 19, 2007

We used to use brake fluid in the garages that I worked at (for gas engines). Simply poured into carbs at approx half-3/4 throttle. Worked great. Not sure if this method can be used on diesel.

Farmerford · Dec 19, 2007

Like Ralph, I used Chevron Techron in Mercedes diesels and it worked well, although you will probably need more than one treatment for heavy carbon. I recall that Chevron recommended only one treatment between oil changes, but I could be wrong.

The Mercedes dealer recommended the Red Line brand and it seemed to work a little better than Techron. And I don't think Red Line had a limit on how often you could use it.

If you can make it through the winter without changing the glow plugs, I would use Techron or Red Line in every tank (if allowed) and work the engine hard

okie350 · Dec 19, 2007

Sea Foam works very well.

montanaman · Dec 19, 2007

dqdave1 said:
How can you remove carbon buildup short of teardown. Glow plugs have carbon buildup and cannot not be removed. Are there any additives or sprays for diesels that can be used to remove carbon. I thought there may be something to spray into intake with air cleaner removed while engine is running to remove carbon.

Can you get them out enough to get anything to run down the glow plugs?? GM used to have a top engine cleaner that worked wonders. Had an engine on a stand to re-do the top end and we set it up so one bank of cylinders was level and poured just enough on each piston to cover the top. The next day, the carbon from the pistons was floating on top of the top engine cleaner and when we wiped it out, the pistons looked brand new.

Ken

skipmarcy · Dec 19, 2007

montanaman said:
Can you get them out enough to get anything to run down the glow plugs?? GM used to have a top engine cleaner that worked wonders. Had an engine on a stand to re-do the top end and we set it up so one bank of cylinders was level and poured just enough on each piston to cover the top. The next day, the carbon from the pistons was floating on top of the top engine cleaner and when we wiped it out, the pistons looked brand new.

Ken

He's right, GM top engine lube was great for removing carbon, we used it back in the 1960's & 70's on Cadillacs & Oldsmobiles. Auto trans fluid works almost as well as the GM stuff, but I have never done a diesel engine with either one so I can't say for sure on that note. I have used water many times as well on gas engines but it would seem obvious that it would be incompatible with a diesel - not supposed to get any water in a diesel.