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Decarbonizing technique

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Michael Oritt

Michael Oritt

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I heard this from an LBC oldtimer today: Pouring a cup or so of water through each carb while the engine is running is a good way of cleaning out the combustion chambers. I have never heard of this and were the fellow who told it to me not so experienced I would have dismissed it out of hand.

So, has anyone ever run across this technique and does it work?

Best--Michael Oritt
 
:yesnod: My uncle who was a "Chevy" mechanic for over 30 years (from the 40's and 60"s) and who also was a USAC racer Sprint cars always told me to do that. In fact, most dealerships did that. You had to start the car and let it good and warm and with the throttle (remember those?) open, pour slowly a cup or two of water into the carb until the engine stalled. Let the motor sit awhile then restart, he called it a "quick tuneup".
 
My take on that is to keep the revs up a ways and pour slowly enough so the engine does not stall. Likewise , I had heard of it but never practiced it. Basically, why bother ? I imagine with modern formulated gasoline building carbon is a long drawn process. Bob
 
Bob, obviously you've never had the head off a car running "modern" gasoline,I've seen the back side of intake valves so fouled w/buildup I wondered how they even run. Also piston tops carboned up beyond belief for the mileage of the engine.Sun equipment sells a stand alone machine for cleaning intakes&valves,BPG does also.Modern gas sucks! cheers Genos2
 
Friends of mine have dropped in a good shot of Redex with the engine reving, that certainly produced some rubbish out of the exhaust.

Bob
 
You can use something more safe to clean out the deposits in your engine that you can buy over the counter, it's called "RXP"(or something like that). It's a small orangish plastic bottle and you pour into your gastank for less than ten dollars. After about 30 minutes of idle or driving your engine is clean. Many cars that fail smog inspections can give this a try before they start buying expensive replacement parts to pass emissions tests. My oldest son had an older van that failed the emissions test and I suggested he try it and he bought a bottle and poured it in and drove back to the testing facility and passed. The facility was impressed how easily and quickly the problem was fixed. I don't know if this will work for our Healey engines but it is worth a try.
Patrick
 
Hello,

if I understand it right, with my language knowledge. You discuss a practice to clean the combustion chambers and the inside of the head, if you fill water in a running machine...
It can be, that nothing is destroyed. But I can`t believe that you remove really the carbon layer. But I see a high risk to crack your head, to crack the pistons, to crack the block....Water is not compressible. Ok, the most water come in a the hot engine as steam, but with which risk ?
It sounds for me as not a practical way.... If you want remove the carbon,without disassembling of the engine,I would buy some cleaning additive from the aftermarket (to fill in the gasoline)
I think that the people believe they clean, because of the steam out of the exhaust...but this is only water.
What I definitly know is, if you have a small broken area in your gasket over a longer time from a water channel to the direction of the cylinder,this cylinder is really clean .

Bye- michel who is wondering which ideas some people have... :confuse:
 
Hi Michael,

Back in the late 50's, in my Ford Flathead days, my buddies in the hot rod club and I used to do that on a regular basis, just to keep the "cobs" blown out.

The theory is that as the cold water hits the hot block, valves, and plugs, the water explodes into live steam and "blasts" the carbon build-up from those internal parts.

Back in those days, most of us ran straight pipes and you could see a LOT of crud coming out of the pipes for the first couple of times it was done.

It seemed to work.

Haven't done it for 50 years though.....

Tim
 
Just so folks know, there is a risk of hydrolocking your engine. Our friend from Germany points out that water is non compressable. In fact, enough water will lock your engine mid revolution and you can bend rods, crack pistons and otherwise damage your engine.

The trick here I guess is to pour a very small amount in so that it flashes to steam and does not stop the combustion process. I would want to watch someone else do it successfully on their car before I gave it a try on mine. If there is something that goes into the tank, as discussed above, that would be my first choice.
 
I use stuff called Seafoam in my boat and my older Explorer.

Brings back throttle response in the 2 stroke boat engine, and gets rid of engine knock in the 302 Ford.

Never tried it in the Healey.

I've heard of the water slowly through the carb technique, but never done it.
 
I used to run a mocked up water injection in my truck. It stopped the pinging on cheap gas and noticably improved gas milage and performance. Tearing down this motor later in its life the combustion chambers were very clean, especially tops of pistons. Looked more like propane had been run thru motor.
 
The steam cleaning effect makes some sense. I would like this idea better if it weren't so unconventional.

If this really works, why isn't it more widely known and used? Is it because it is free and nobody gets to sell anything?
How do gasoline additives work to get a similar result (if they do)?

Seems to me we really need two dirty engines and before and after inside pictures to settle it. One for the water method, one for an additive. The benefits seem to make this worthwhile.
 
You mean like water injection used on airplanes during WW II before the jetage?
 
I once worked on a '64 Chevy that had a head gasket leak that leaked water into one of the cylinders. That cylinder was completely clean of carbon when I pulled the head.

I would get a spray bottle and spray the water in rather than pour it. Much easier with side-draft SUs and it would keep you from pouring in too much at a time.
 
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