Vacuum intake manifold or Air intake?

[Omega]

Yes, I have my generator gas exit just past the air box. I have a diesel, so dont have the vacuum options.

When running the generator on vacuum with a check valve between the bubbler, you need to make sure your generator has a small leak or something. The reason is as follows. The greatest vacuum is created at engine idle. Lets say your engine produces 20Hg at idle. Your hho gen is now at 20Hg as well, then when you step on the gas pedal the engine vacuum drops below 20Hg. That will cause the check valve to close which will not allow the HHO gen to equalize the vacuum pressure because the hho gen vacuum is greater than the engine vacuum. This will especialy become a problem in city driving.

That's why I've changed from a vacuum line to the air intake for putting the HHO into the motor. I live in the mountains a coast a lot, so the generator saw lots of max. vacuum time. It's necessary to leave some air space in the top of the generator which creates more problems with a significant vacuum "volume" that is very powerful. My generator was completely sealed with no leaks and the problems were numerous.

The biggest problem with the vacuum line hookup is the lower boiling point of water at a vacuum. A running temperature of 160 or 170F becomes boiling at a certain vacuum level. So "thermal runaway" can occur under a vacuum when it wouldn't if hooked up to the air intake.

The vacuum effect in the bubbler was an issue I couldn't overcome. Water would get sucked out no matter what I did. The advantages of hooking up to a vacuum line are far outweighed by the disadvantages, IMO.

With my HHO input going to the air intake, I have no loss of water out of the bubbler and no problem leaving an adequate air space in the generator. The car actually seems to run better with the current hookup, too.

[HHOhoper]

I agree. I've investigated the vacuum from the air intake and I was surprised that on both of my cars the hose still produced enough vacuum that I'm convinced it's still sucking a considerable amount of gas without putting a huge vacuum pressure on the cell.

[RMForbes]

On my car I used both. I have a line that T's into the crankcase vent hose that enters the intake just before the butterfly valve, and ran a line into a main vacuum port. I added a valve to the vacuum line so I could reduce the vacuum to the cell at idle to the same as the cell was producing. This is easier than it sounds because when the cell is under vacuum the water level rises, so I just watched the water level in the cell and the bubbler adjusting to the max gas output without rising the cell water level. Both lines have one way check valves inline so when the engine vacuum drops that check valve closes and the gas from the cell flowes to the other line.

[Stratous]

Currently, I have built 5 cells. I have found that a large vacuum will slowly cause the container seals to leak. The last cell sat for 6 days with no leaks, then ran under vacuum for 1 day. The next moring after sitting unused for the night, I discoverd a leak. I am certain that the vacuum caused the leak.

[countryboy18]

if the cell is under vacuum then the water will boil at a lower temp. so what is the problem with the water boiling. if the temp is the same weather under vacuum and at normal presure then what is the problem with the water boiling. another thing you can do is use antifreeze insted of water or do a mix of the two to reduce the chance of it boiling.