Carbon removal with water spray...?

[HammerDown]

Anyone done it...I recall hearing about doing this back in the 70's and 80's.
Feedback?

[SoLow]

Originally Posted by HammerDown

Anyone done it...I recall hearing about doing this back in the 70's and 80's.
Feedback?

Did it back in the day ..... .....NOT for the faint of heart as it sounds like your motor has ingested a box of BB's.........The theory is that the water bounces around the valves and knocks off the carbon build up.

We did it by pouring water s-l-o-w-l-y out of a coke bottle into the carb as the motor was revved to about 2000 r.p.m. It will pop like pop-corn..white smoke for about 10 minutes then be OK. We also used ATF but it would smoke for a day after doing it. OLD-TIMERS did it back then and showed me how.....Oh to be young and dumb again

[Bill75]

Originally Posted by SoLow

Did it back in the day ..... .....NOT for the faint of heart as it sounds like your motor has ingested a box of BB's.........The theory is that the water bounces around the valves and knocks off the carbon build up.

We did it by pouring water s-l-o-w-l-y out of a coke bottle into the carb as the motor was revved to about 2000 r.p.m. It will pop like pop-corn..white smoke for about 10 minutes then be OK. We also used ATF but it would smoke for a day after doing it. OLD-TIMERS did it back then and showed me how.....Oh to be young and dumb again

You wern't the only one! I had a 396 Chevelle that we used to SLOWLY pour STP oil treatment down the carb while revving the engine to keep it going. TALK ABOUT SMOKE!!! Man what a cloud! All sorts of carbon would come out of the exhaust though, I think it actually did work taking the carbon off the pistons. Well, the carbon came from somewhere not sure it was the pistons but it was always on the ground under the tailpipe when we were done.
It might not work but it was fun to do!

Bill

[Yoda]

You can add me to the "water down the carb" treatment..

I had a 67 Corvette years ago and had it at a body shop getting a new front clip and paint job. It was there for almost 10 months, when the body/fender guy called and said it was done, he also mentioned bringing a trailer to haul it home Seems it develop a very loud "knocking" sound.

I started it up and sure enough it sounded like the engine was tearing itself apart When I got it home I called a buddy that built engines for local racers and had him come over. I started it up and shut it down RIGHT AWAY, he said let it run, then took a long screw driver and started listening all over the engine. FINALLY he said shut it off, go get a bottle of water.

We started it up again, then he started pouring the water down the carb, and within a few seconds (which seemed like minutes) the knock went away and the 67 LOOKED good and RAN great..

My buddy has since passed on, but I will never forget this experience nor the friendship of Howard Hubka from Central City, Nebraska

Bud

(Howard’s diagnosis was a piece of carbon the top of #4 piston..)

[Tom Bryant]

Yep, what Bud said. It used to be common for carbon to build up on pistons of cars in the early '70 to a point that the valves would actually hit and cause a knock. GM came out with a carbon desolver called Top Engine Cleaner that you poured 1/2 of the can down the carb running the engine fast then poured all the rest down all at once stalling out the engine. You let it set and desolve for a period of time then restarted the engine reving it to blow out the carbon. The product is still available.

Water will do the same thing except for the soaking part. Steam cleans the piston, valve heads and chambers. If you have a mid '70s era car with a pellet type cat converter be sure to disconnect the converter from the front pipe or it will just load up with debris and become plugged. Then you get to buy a new converter.

Tom

[HammerDown]

So would I be ok for me to use a spray bottle with a (fine mist)... or dribble some water down the carb ?

[SoLow]

Originally Posted by HammerDown

So would I be ok for me to use a spray bottle with a (fine mist)... or dribble some water down the carb ?

DRIBBLE as you would atomize the water if you fine misted it in.

[HammerDown]

Uh...am I suppose to see white smoke out the tail pipe and maybe hear some popping and crackling noises?
Because nothing really happened when the engine in-jested the water at 2000 rpm

[mainelaker]

I still have a can of GM's top engine cleaner in the garage somewhere. Go to a GM garage & see if you can buy some, it is pretty good stuff, better than water when I used to use it.