water treatment for valves???

[old_chopper]

I heard an engine stop like that several years ago at the Buffalo Chip. Some dude has his bad crotch rocket on the burn out ramp lighting the rear tire up. He buzzed thru the gears and had it revved to the moon. A few seconds later there was a "THUNK" and then a brief silence, then thousands of people screaming and cheering. The rider was not part of the cheering! The bike didn't look very old, like maybe still being payed off...

[rkjjeep]

the water thing works, but brings the risk that you will catch a piece of freed carbon off the piston between the valve and seat, bending the valve. Seen it happen. Do the water thing as a LAST resort.

[ddominik]

I recall in the late 70's there was a company marketing a water injection system for cars and trucks. The claim at the time was better gas mileage. Remember the gas shortages and sitting in a gas line for hours?

A friend installed one in his big block truck and claimed a modest (?) increase in gas mileage. He didn't trust the metering device so it got pulled soon after.

.... just another useless piece of info floating around my brain .... but at this point in my 64 years .... nostalgia is entertaining ...

Well ... 70 out there today ... time to go riding .... ain't retirement GREAT!!!!

Later
Dom

[BassCliff]

it sounded like snake oil to me so i threw it out there....i know i need to do the valves on both my zukes soon.. I am a bit timid about it though..I was looking at the search for some tolerances for the 750 8 valve but hadnt seen it yet.. i was thinking that from waht i have seen is too shoot for a .04mm overall tolerance..

Hi,

I documented one of my valve adjustments with pictures. You might find it helpful. The link to my website is in my sig below. The range spec is .03mm - .08mm for these 8-valve shim over bucket motors. I'd be leery about spraying water into my engine. Sure, it might work but, for me, it's too gimmicky without much return for the effort.

Thank you for your indulgence,

BassCliff

[oldgrumpy]

tinkering with water injection.....

an old mate of mine in toowoomba,, queensland ..sam pisarski.... use an ols international vergi truck ,,,petrol engine to travel to different districts ,,buying and selling tyres regrooved .. anyway to make it more economical he put a water injection system on the truck with a 44 gall/ drum in the back delivering the water to the engine ,, everything worked well untill 1 night he went to bed late and left the water system on,, and it filled up all the cylinders over night and THUS placing rust on the linings of the cylinders ..hope this helps regards david

[BIKERTUCKER]

Per my stepdad, who was a mechanic for the U.S. Airforce from 1950 till early 60's spraying water into the intake of Radial engine's on aircraft was routine maint. Said the first time he preformed task it scared him. Carbon shot out the exhaust so hard it would impact the plywood mounted on the back wall of the shop like bullets. He said carbon build up on valves could also cause valve train to become noisy. Not sure if newer composit metals would respond poorly to same treatment. Just thought I'd throw in his story that Uncle Sam at one time taught it to their mechanic's who in turn preformed it as routine maintenance.

Tim

[Nessism]

.... just another useless piece of info floating around my brain .... but at this point in my 64 years .... nostalgia is entertaining ...

Well ... 70 out there today ... time to go riding .... ain't retirement GREAT!!!!

Later
Dom

Enjoy your retirement Dom, and don't let your mind wonder too much while blasting along those Tennessee two laners.

[gggGary]

We want data! Wish I had tried this on my recent 11E purchase before I tore it down, the only thing really wrong with her was carbon build up. Ideally someone will do 2 out of 4 cylinders on a high mile motor and then tear it down and compare to see what it did. Anyone going to tear one down anyhow?

[teddux]

Your engine wasn't designed for water injection.
Called WEP on WWII Aircraft.

"All WEP methods result in greater-than-usual stresses on the engine, and correspond to a reduced engine lifetime. For some airplanes, such as the P-51, use of WEP required the plane to be grounded after landing and the engine torn down and inspected for damage before returning to the air."

You can also run your bike on water and fuel fumes...@ your expense, of course.

[chuckycheese]

Agua

I tried it several years ago. I don't think it hurt anything but I also don't think it did any good. Could have been my technique!!

[themess]

I've never seen an engineering/thermodynamics analysis of water injection, but without one I would not intentionally inject or squirt water into an engine.

If an engine is adjusted and tuned, valves should never have that kind of carbon build up.

Water in an engine doesn't release oxygen.

The energy required to vaporize water only takes power away from the engine. It cools the gases in the engine, so they don't occupy as much volume at the same pressure. Therefore, more fuel must be burned, which requires more air. More fuel, more air, yes, higher compression ratio. But if it gives more power, it won't give a huge increase in power.

Tune the engine properly and skip water.

[BIKERTUCKER]

I thought the question was the use of a spray of water mist to clean valves as a form of maint. Not constant injection of water as a means to increase hp.

[chuck hahn]

it was trucker..an old coot told me they used to do the mist in the carb thing to be sure all the carbon was off the valves before they did the shimming and adjusting.. said it made sure the valves were seating all the way so you could get the best possible readings when checking the valve clearances..just a few good mists into each carb ..

[rustybronco]

Do you want a sure fire way of removing excess carbon in the combustion chamber?

start up an engine and advance the throttle while retarding the timing. you'll see the glowing embers of carbon exiting the exhaust.

It worked well on lift trucks but I would NOT recommend doing it on an air cooled motor

[jimfj]

I don't want to make a recomendation on this but I'll give up some personal expirience.

I had a 1976 Glastron runabout with a straight six chevy blocked motor. Great running old girl and fun on the water. One day as I was doing some pre M and this started with changing some old plugs. I had noticed some hesitation and was just trying to establish a baseline. I did a compression test on the motor with all the plugs out of the block. As I turned the motor over I noticed some liquid (water) misting into one of the cylinders. I stuck my trusty led bendable flashlight into the said cylinder and found it to be spotlessly clean. Carbon in every other and a little build up on the piston crowns. This one had nothing, again spotless.
Time to change the headgasket. Once that was done it looked like all the others and the plug was the same color. Hesitation gone.

Moral of the story. IMHE water will clean the carbon out of a cylinder, very well. Like anything we do thats not procedure in the manual, you run a risk. I'm also wondering if the people who told you this weren't going back to the two-stroke days when carbon really was a huge problem and you had to de-carbon things all the time.

my .02