Water treatment

[R.White]

Something that I know can be done to remove carbon build up from an engine is adding a little water to the carb intake. I must admit that I have never done this myself; having known a number of engines be destroyed by water getting into them when cars have been driven through flooded areas, has made me somewhat wary.

Has anyone with personal experience (who hasn't blown up their engine!) got the answer to how best to do this safely when the carb is an updraught? Would it be possible to use the windscreen wiper vacuum pipe? (perhaps with a restrictor of some kind) or does it need a mist spray into the carb? Obviously, only a small amount of water at a time is safe and presumably applied to a hot engine and to leave running afterwards just to be safe.

I bet some of you guys have done this - braver than me!

Ray.

[Phil 32DL6]

I think first I'd want to know the answer to: "How do I know this is necessary?"

[keiser31]

I have seen it done to an updraft by an old mechanic. The spray mist is the way he did it. Needs to be done VERY SLOWLY and someone must be on the throttle to feather it or it may die. Gotta keep it running. Works really well.

[Pete K.]

Yes, this will work, but I have to mention I believe the modern, chemical, gas treatments may be an easier way to go. If they won't work, I think one would need to un button the engine and do some scraping. I use a product called "Seafoam", a gas and oil treatment and stabilizer to boot. It works well and seems to do what the can says it will do. Did you know some early, large aircraft had a water injection system for their engines? It was definitely not for removing carbon, but for added power on takeoff!

[R.White]

I guessed this would get some reactions! To be honest, it is something which has got me thinking quite a lot about 'old school' methods. I should imagine, although I don't know for sure, that this practice would have been quite common before the introduction of detachable cylinder heads on engines, when carbon build up would have been a much more serious problem - especially in commercial vehicle down time and would have been a quick fix. Even if my engine did suffer from pinking (what we call pre ignition here) was choked with carbon and needed a decoke, I still think I would be too nervous to try it. Perhaps on a scrapper, just for fun.

Ray

[Machinist_Bill]

Never heard of water. When I was 16 we used a spray bottle of kerosene and while the engine was running spray into the carb. It would idle sooooooooo much better after 5 minutes of spray. When we were done we sprayed the outside of the car to make it shine for Friday nights!

Todays engines don't run rich like the old carbs. Every newer engine I've rebuilt are VERY CLEAN!

[R.White]

Quite right Bill. We were subjected to some pretty awful small (8hp) Ford engines in the past which would choke up readily. Also they didn't last too long but then they were dirt cheap to replace. You pay your money and get what you pay for. My first car was one of these - they were practically worthless second hand. You don't know what you've been missing!!

Ray