water decarbonization...

[acranox]

Okay, so I decided to try the water through the PCV system trick on my 87 Honda Accord. I know there is carbon buildup on the pistons.

Anyhow, I took out the PCV valve which is mounted into the intake manifold. One side has a pipe which runs down towards the block, and the other side seems to go towards the carburetor. There should only be vacuum on the intake side of the valve, right?

Anyhow, I hooked up a hose, and put some water in the cup, sat in the car, and held the revs at about 3000 and held the hose at the surface of the water and let the hose just suck up the water. The vacuum was real strong, and it took the water pretty quick. I did 4oz at a time, 4 times total.
I had a piece of plywood propped against the back bumper to catch the spray out the tailpipe. I checked the plywood after each time, and I didn't see any signs of water. I've got a big hole in the exhaust, which I'm fixing now, but I didn't see signs of steam there either.

So I decide to stop, and change the oil since I know that should be done afterwards.
It looks to me like all the water went into the oil. I took the valve cover off and there was signs of water in there. What did I do wrong?

 

[mechtech]

Sounds like a workable technique.
I don't know how the water got in the engine internals.
Not seeing water vapor in the exhaust is normal.
Steam is invisible - it's a gas.
Only condensed water vapor is visible. That's why you see water coming out of tailpipes only when the engine is cold, at start up.
Get the engine good and hot, and the water in the oil will evaporate - no harm done.

 

[TallPaul]

Could the PCV system have sucked the water directly into the crankcase? Normally I would use a manifold connected vacuum line for this. I ran 22 ounces of water through mine (14 through a sprayer bottle and 8 poured in over a couple minutes) and did not see any sign of water in the oil.

 

[Kestas]

No, it couldn't happen. The crankcase doesn't have vacuum, only the intake manifold has vacuum.

I use a similar method, but plumb it up for treatment during highway driving.

 

[Gary Allan]

No, it couldn't happen. The crankcase doesn't have vacuum, only the intake manifold has vacuum.


I wouldn't say that. My BMW wouldn't run with the oil cap off ..or the dipstick pulled (well ..it would go into convulsions with just the dipstick pulled).

He needs to verify that the line that he's pouring the water into attaches to the manfold below the throttle body on the intake. For all we know via remote viewing ..he used the fresh air vent.

That would explain water in the oil if this was the case.

 

[Kestas]

You're right. But acranox mentioned he used the pcv valve by removing it and introducing water through it. How could the crankcase see vacuum, and more importantly, how could water find its way into the 87 Honda crankcase under those conditions?

 

[Gary Allan]

I see what you're saying ..but we don't know if acranox is truly referring to the pcv valve ..or just the grommet to some place in the pcv system. We're taking his word for it. The only reason I'm suggesting that this is the case is that they result kinda leads me to believe that something is "unright" with his description of what he did

 

[acranox]

No, I didn't actually use the PCV valve. Okay here's my best description. There is a piece of hose, about 4 inches long that forms a loop, and both ends connect to the intake manifold. One side of the hose has the PCV valve, which pops into a grommet. On the side with the valve, it appears that it is just a bracket, there is a hose that goes down below the manifold. The other side, has a casting which heads towards the base of the carb.
On the side without the valve is where I attached a hose. There was a very strong vacuum, and if I didn't plug the hose, the car would stall (i figure it leaned out the mixture too much)

That vacuum had to have been generated in the intake, but after everything was done the oil seemed really thin. It's 10W-30. And there were signs of frothyness in the valve cover.
As I said, there was a piece of plywood up against the back bumper to catch anything that came out the tailpipe (people reported chunks of carbon coming out, and my sister's '03 civic was parked there) Shouldn't there have been signs of steam on the plywood?

It really seems like the water mostly went into the oil, but I'm not sure how.

Oh, also, there is a hose from the valve cover to the air filter housing, called a blow-by hose, and there was definitely some water in there.

 

[acranox]

quick question.
What effect, if any, does the water decarbonization trick have on spark plugs?

 

[Gary Allan]

Hmmm ...I'm still lost here

You're describing a "Y" tube configuration. If it's just one piece of tubing ..then the base of the carb to the PCV valve grommet should be the only thing there. You're asserting that there is somewhere else this goes. This implies a "third member" to this single piece of tubing (see why I'm

).

quote:

---

and both ends connect to the intake manifold.

---

Then what "other end" is attached to the PCV valve and gets inserted into the valve cover ...or did you mean "of the three "ends" ..two attach to the intake manifold???

 

[acranox]

No, it's not a Y.
Clearly a picture would be worth a thousand words. Or at least a hundred here, but I don't have a picture available now.

Thanks for the help though.
I'm sure that the water was going into the intake, it had to have been. I guess maybe there was just enough blowby to put a lot of the water into the oil. I'm going to just treat my car right, and not do anything drastic, and let it live out the rest of it's life, which hopefully is another year or two.

 

[Winston]

It does all sound really strange. I cannot imagine that there is so much blowby that the oil would turn gray. Pcv valve with two tubes sounds strange too. PCV valve mounted on the intake manifold sounds strange too. No black crud on the plywood sounds strange too.

Driving the car to burn off the water from the oil is not such a great idea either. I would change the oil. He did four ounces four times. That is a lot of water.

IMHO

 

['Tard]

Just spray into the carb with a spray bottle. Why did you make it so complicated?
The 'blowby hose' sounds more like your PCV system anyhow.
Did you do this when the engine was hot? Thats required for this to work. I mean run hard hot, not just warmed up.