Rotten test run - need help!

[RobertC]

Did an HHO test run in a diesel RV. The bus is a full size coach at 40,000 lbs. Engine is a Detroit diesel 8V-92, 2-stroke. Displacement is of course 92 cubic inch per cyl. the math puts it at 12 liters. I built 2 dry cell units each with 2 stacks configured with 9 neutrals per stack. Between both cells there was 44 plates. the plates measured 5.25 by 7.5 inches with a 1/2 wide gasket. After several tests I found the best gasket thickness was .25 inch. Total output was a steady 12 liters per minute drawing 60 amps per dry cell.



We filled the tank drove 182 miles and refilled at the same pump. Mickey (the bus owner) said he got a steady 5.7 mpg before HHO. Our test mpg was 6.1 mpg. This was an increase of only 7%. I was very discouraged wit a .4 mpg improvement. We were hoping to get perhaps 1.5 mpg or better.



Would love to get any advice or input you guys have as to what to do to improve results.

RobertC

[Buster]

Just one thing I would look into.....

One of the main advantages of an HHO installation is the potential to increase the air to fuel ratio. This is what NASA's research highlighted, namely, that HHO allows a leaner fuel mix than is possible with straight fuel alone.

Presently you are only experiencing some of the potential gains from your HHO, I would guess, and by leaning the fuel mix you could achieve the rest of it's potential. If this is an old vehicle this adjustment may be simply a turn of a screw, but if it's a modern vehicle with an ECU you would need to use electronic means such as an Efie or AFC. I think some of the more electronically minded members may be able to give you some more help in this regard.
I hope this is of some help.

[hhonewbie]

Same as above & being a 24V application it might need reconfiguration(plate gaps, N plates, etc.) for efficiency & increased production.

[RobertC]

Hey,

Thanks for the replies, here's more info on the bus. The Detroit Diesel is all mechanical, no air to fuel ratio adjustments, no computer. I've learned that on a diesel 2-stroke, the turbo blows air into the cylinder when the piston approaches the bottom of the stroke. At this point the exhaust valve is opened and the force of the turbo (not the piston) blows the burnt gases up and out. My question is, how much air travels through the cylinder before the piston rises and closes the intake ports? Is there 2 or 3 times more air passing through the cylinder than is necessary? If so, we are blowing excess hho through the cylinder and out the exhaust unignited.

Some weeks ago I talked to an HHO seller and he told me that 3 liters per min. was a good starting point for a diesel that size. He further said that his bus (of similar size) has gained about 1.5 mpg with hho. He also said that “the more the better” and we really can't put too much to the engine. So I felt 12 lpm would be a measurable amount to work with.

When I was bench testing the cells I had to jump across both mine and my wife's car to get 24v to run the cell. Note: wife was not thrilled seeing this, had to cancel a trip to Wally-Mart :). As the cell drew more current (25 A) the voltage dropped to about 22v. Confident that the cell was in working order I installed it on a luggage rack slid into the bus hitch receiver. The bus had 2, 8d batteries in the engine compartment plus 4 more (8d) house batteries up front. This fed the cells with 27+ volts at more amps that the cells could handle with the engine running. Using 2, 60A pwm's I could easily feed 100 amps per cell. Had to throttle back to 60A to keep the pwm's from heating up. I was testing the hho output with a ½ liter bottle inverted in a column of water. The bottle would fill up in two and a half seconds. WOW! So I constructed a 2 liter bottle hhometer to give more accurate readings. Now the bottle would fill In 7-10 seconds measuring a solid 12 to 15 lpm.

Question: is the hho injection point critical? Ours was in the 8” rubber hose connecting between the air filter and turbo. From the nipple to the turbo is about 18”. Does it need to be as close to the turbo as possible?

Mickey is in the HVAC test and balance business. So he had the gauges to test the pressure in the intake line at the hho injection point. It was 2.5 inches negative to outside air. So we felt confident that the hho gas was not leaking out of the intake line.

I am really stumped at the poor results of the trip. So any questions and advice you have is welcome.

[doityourselfer]

Robert, did you ever get anywhere with this coach bus

[BioFarmer93]

Did an HHO test run in a diesel RV. The bus is a full size coach at 40,000 lbs. Engine is a Detroit diesel 8V-92, 2-stroke. Displacement is of course 92 cubic inch per cyl. the math puts it at 12 liters. I built 2 dry cell units each with 2 stacks configured with 9 neutrals per stack. Between both cells there was 44 plates. the plates measured 5.25 by 7.5 inches with a 1/2 wide gasket. After several tests I found the best gasket thickness was .25 inch. Total output was a steady 12 liters per minute drawing 60 amps per dry cell.



We filled the tank drove 182 miles and refilled at the same pump. Mickey (the bus owner) said he got a steady 5.7 mpg before HHO. Our test mpg was 6.1 mpg. This was an increase of only 7%. I was very discouraged wit a .4 mpg improvement. We were hoping to get perhaps 1.5 mpg or better.



Would love to get any advice or input you guys have as to what to do to improve results.

RobertC

Before anyone hammers me, I know the thread is almost 4 years old- it does bring up an interesting point though about two-stroke jimmy's. To get equivalent gains in mpg you would have to make TWICE as much HHO, because besides the slight wastage of unburnt HHO used in the exhaust purge of blown 2-stroke GMC diesels, the cylinders are firing on every other stroke, rather than every fourth stroke. Big difference in the the amount of intake air between one of these Jimmy's and a 12L Cat or Mercedes at 1800rpm. I think a 1.5mpg gain in this instance is about right on target..

[myoldyourgold]

Bio I agree unless he goes post turbo which I have not tried on a two stroke. I would like to try though.

[BioFarmer93]

Bio I agree unless he goes post turbo which I have not tried on a two stroke. I would like to try though.

Hey Carter,
I think I must have missed the boat on that little change- not that I think the overall amount of HHO necessary is actually dictated by the pre- or post- turbo injection point, as has been the sea change on this forum over the last year or two, but the straight up fact that you're having a power stroke every revolution rather than every other revolution necessarily dictates that you will need twice the HHO. Take Care- Gus

[myoldyourgold]

Bio, I have some doubts popping up in my mind about needing twice as much HHO in a 2 stroke. That would mean that a 2 stroke uses twice as much fuel to make the same HP as a four stroke. Help me out here. On first thought I agreed but this nagging doubt has popped up. I need to think about this a little more. I think it can not be related simply to 2 or for stroke but the volume of air and fuel ratio to HHO ratio, regardless of 2 or 4 stroke, that is running through the engine. If there is twice as much fuel per power stroke in a 4 stroke compared to a power stroke in a 2 stroke then yes if not then no. Does that make sense. Like I said I need to think about this a little more.

[BioFarmer93]

Bio, I have some doubts popping up in my mind about needing twice as much HHO in a 2 stroke. That would mean that a 2 stroke uses twice as much fuel to make the same HP as a four stroke. Help me out here. On first thought I agreed but this nagging doubt has popped up. I need to think about this a little more. I think it can not be related simply to 2 or for stroke but the volume of air and fuel ratio to HHO ratio, regardless of 2 or 4 stroke, that is running through the engine. If there is twice as much fuel per power stroke in a 4 stroke compared to a power stroke in a 2 stroke then yes if not then no. Does that make sense. Like I said I need to think about this a little more.

Well, I guess if the exhaust gas purging is sufficient (via blower) to provide all clean air for the compression stroke, then a blown two stroke 6 cyl. diesel should probably make more horsepower at a given rpm than a turbo'd 4 stroke 6 cyl. diesel. Why? My thinking is that at any rpm the two stroke is hitting on every cyl. every revolution, where the 4 stroke is only hitting on half of its cyl's every revolution. But, this doesn't answer your question does it? Since reading your response, I have been thinking about it more- diesels don't really run "rich" or "lean", they just run fast or slow... So- (thinking now, watch out for flying debris) if power stroke every revolution, then perhaps (probably) less fuel per injection because of double the number of power strokes for any given rpm? If not less fuel per injection, then roughly double the rpm? If it is truly only necessary to use half the amount of fuel to attain a given rpm, as may be the case, then yes I agree with you, the HHO usage ratio should be similar... Take care, and thank you for helping to shake out some of the cobwebs ;):D

[TwinTurbo]

I have a few thoughts to contribute to this discussion since i have some experience with both engines, i can only speculate though on the hho portion, first off I realize you guys know alot of what i'm going to post but will include some basics for others reading. The 8v92 is as has already been established, a two stroke supercharged (mechanically driven blower) diesel engine. Now the ones i'm more familiar with also had a turbo feeding the blower, which in itself is a needed variable in the equation to determine how much air is moving through the engine. A two stroke is going to flow almost double the amount of air (CFM's) as a 4 stroke of the same size (CID) at the same rpm's. I say almost because of the inherent inefficiencies of the two stroke you are not able to completely fill the cylinder to its total volume or completely remove all exhaust gasses until you add forced induction which i will get to in a moment. While they are capable of making more power than a 4 stroke, they require higher rpms to do it, so again, more air moving through the engine. as an example, and for easy figuring lets use a 500 cubic in motor, in one revolution of the crankshaft, it requires 250 cubic inches of air for a 4 stroke, 500 for a 2 stroke (not figuring in boost pressure for either one) now if the 4 stroke runs at 1800 rpms for peak power it requires a flow rate of 260 cfm. If the two stroke makes its peak power at 2500 rpm, it is flowing 723 cfm's. now if we figure in the volumetric efficiency (1.6 for the turbocharged 4 stroke, 1.9 for the turbo and supercharged 2 stroke) the requirements become 417 cfm and 1374 cfm respectively. So now we have more than tripled our air requirement and I can only assume that if the hho is not increased at the same ratio it will have become to diluted to offer much if any benefit. Correct me if I am wrong but it would seem that tuning for the proper hho amount should have just as much, if not more, to do with the amount of air going in than the fuel should it not? I don't know if that helped at all but I feel like i at least tried to contribute something to this forum finally :) On a side note i have built my first generator of my own design and am in the testing process, but that's for another thread.

[myoldyourgold]

I have a few thoughts to contribute to this discussion since i have some experience with both engines, i can only speculate though on the hho portion, first off I realize you guys know alot of what i'm going to post but will include some basics for others reading. The 8v92 is as has already been established, a two stroke supercharged (mechanically driven blower) diesel engine. Now the ones i'm more familiar with also had a turbo feeding the blower, which in itself is a needed variable in the equation to determine how much air is moving through the engine. A two stroke is going to flow almost double the amount of air (CFM's) as a 4 stroke of the same size (CID) at the same rpm's. I say almost because of the inherent inefficiencies of the two stroke you are not able to completely fill the cylinder to its total volume or completely remove all exhaust gasses until you add forced induction which i will get to in a moment. While they are capable of making more power than a 4 stroke, they require higher rpms to do it, so again, more air moving through the engine. as an example, and for easy figuring lets use a 500 cubic in motor, in one revolution of the crankshaft, it requires 250 cubic inches of air for a 4 stroke, 500 for a 2 stroke (not figuring in boost pressure for either one) now if the 4 stroke runs at 1800 rpms for peak power it requires a flow rate of 260 cfm. If the two stroke makes its peak power at 2500 rpm, it is flowing 723 cfm's. now if we figure in the volumetric efficiency (1.6 for the turbocharged 4 stroke, 1.9 for the turbo and supercharged 2 stroke) the requirements become 417 cfm and 1374 cfm respectively. So now we have more than tripled our air requirement and I can only assume that if the hho is not increased at the same ratio it will have become to diluted to offer much if any benefit. Correct me if I am wrong but it would seem that tuning for the proper hho amount should have just as much, if not more, to do with the amount of air going in than the fuel should it not? I don't know if that helped at all but I feel like i at least tried to contribute something to this forum finally On a side note i have built my first generator of my own design and am in the testing process, but that's for another thread.

Great contribution. This is one thing that is not taken into consideration and that is the amount of remaining exhaust in the two stroke compared to the remaining exhaust in a 4 stroke. In my limited testing on a 2 stroke (not a diesel) I found over all for the same HP it took less HHO than a 4 stroke. I am not sure how that would apply to the diesel and have no good explanation as to why but I think is has to do with the oil in the fuel of a gasoline 2 stroke when you add HHO. It seams to make more HP at lower rpm. Depending on the amount of exhaust left in the combustion chamber one could be making other very explosive gases in the combustion chamber too which would contribute to the process. Like you said to make the same HP it would be at higher rpm normally and here again it is going to depend on how the timing of the ports are. To build bottom end power there is less over lap and power is built at lower rpm. It would be interesting to here from someone who has actually put HHO on a 2 stroke diesel. Some times HHO does not follow the logical and theoretical explanation.

[BioFarmer93]

I have a few thoughts to contribute to this discussion since i have some experience with both engines, i can only speculate though on the hho portion, first off I realize you guys know alot of what i'm going to post but will include some basics for others reading. The 8v92 is as has already been established, a two stroke supercharged (mechanically driven blower) diesel engine. Now the ones i'm more familiar with also had a turbo feeding the blower, which in itself is a needed variable in the equation to determine how much air is moving through the engine. A two stroke is going to flow almost double the amount of air (CFM's) as a 4 stroke of the same size (CID) at the same rpm's. I say almost because of the inherent inefficiencies of the two stroke you are not able to completely fill the cylinder to its total volume or completely remove all exhaust gasses until you add forced induction which i will get to in a moment. While they are capable of making more power than a 4 stroke, they require higher rpms to do it, so again, more air moving through the engine. as an example, and for easy figuring lets use a 500 cubic in motor, in one revolution of the crankshaft, it requires 250 cubic inches of air for a 4 stroke, 500 for a 2 stroke (not figuring in boost pressure for either one) now if the 4 stroke runs at 1800 rpms for peak power it requires a flow rate of 260 cfm. If the two stroke makes its peak power at 2500 rpm, it is flowing 723 cfm's. now if we figure in the volumetric efficiency (1.6 for the turbocharged 4 stroke, 1.9 for the turbo and supercharged 2 stroke) the requirements become 417 cfm and 1374 cfm respectively. So now we have more than tripled our air requirement and I can only assume that if the hho is not increased at the same ratio it will have become to diluted to offer much if any benefit. Correct me if I am wrong but it would seem that tuning for the proper hho amount should have just as much, if not more, to do with the amount of air going in than the fuel should it not? I don't know if that helped at all but I feel like i at least tried to contribute something to this forum finally :) On a side note i have built my first generator of my own design and am in the testing process, but that's for another thread.

-Indeed.. Which puts the ball back into the court of my original premise, with the caveat that fueling (Myold) amount vs. HHO amount will also play a role. I suppose I'll have to buy a screamin' Jimmy to test to know for sure. Another diesel, oh darn...

[TwinTurbo]

-Indeed.. Which puts the ball back into the court of my original premise, with the caveat that fueling (Myold) amount vs. HHO amount will also play a role. I suppose I'll have to buy a screamin' Jimmy to test to know for sure. Another diesel, oh darn...

Yup - I've got one in a '73 Peterbilt, runs great just to many irons in the fire and not enough fuel to keep it lit:rolleyes:

[myoldyourgold]

I made a preliminary proposal a few years ago to add HHO to a Wartsila Sulzer RTA96C 12 cylinder, which required some major rehashing based on further testing. The Sulzer RTA96C type engine is a low-speed, direct-reversible, single-acting two-stroke engine, comprising crosshead-guided running gear, hydraulically operated poppet type exhaust valves, turbocharged uniflow scavenging system and oil cooled pistons. The Sulzer RTA96C is designed for running on a wide range of fuels from marine diesel oil (MDO) to heavy fuel oils (HFO) of different qualities. I have been working on the revised proposal but am waiting for some further testing to be completed before I complete it. Unfortunately I had to sign a very tight Non-Disclosure agreement so can not post any details. I think for one where we are a little confused is in the fact that you are assuming a much higher rpm and I am not. The above referenced engine is only a 102 rpm engine with a maximum output for the twelve-cylinder engine of 68,640 kW. This engine weighs over 2 metric tons and is found in many container ships. To complicate everything the engine not only burns 171 g/kWh of fuel but also burns slightly less then 2 gallons of engine oil per kWh after it is broken in.

Main features:
Bore>>>>>>>>>>>>>>960 mm
Stroke>>>>>>>>>>>>>2500 mm
Number of cylinders>>>>>6 to 12

Main parameters (R1):

Power (MCR)>>>>>>>>>5720 kW/cyl
Speed (MCR)>>>>>>>>>102 rpm
Mean effect. press.>>>>> 18.6 bar
Mean piston speed>>>>>>8.5 m/s

Additionally we need to consider the amount of hydrocarbons that the HHO can react with, the formation of highly reactive nitrogen elements, other gases some unknown all formed in the combustion process which add additional HP by using the HHO and wasted heat from the combustion process. This wasted heat would normally go out the exhaust or into the cooling system. Things are not totally like one would think. More testing is necessary before I am willing to make a final decision or statement so as not to mislead anyone because of the many variables not yet tested. To put it simply there is more to it than just the volume of air per power stroke to calculate the amount of HHO needed. Of course this has to be taken into consideration when trying to get the ratio correct but all the rest is just as important. I would be very interested in anyone's experience using HHO with both 2 stroke and 4 stroke diesels especially ones with EGR's and water injection.