WI

[dax021]

I have finally got a batch of WVO ready for consumption in my SR2, but am reluctant to try it without WI.  I still haven't got my head around how to install WI, but remember reading a post where someone modified an oil bath filter to feed water into the intake.  To me this would be the easiest solution, but am concerned about whether it will work and also whether the filter will still work as an air filter, not having the oil bath.  I know Ed and Glort will be able to advise.


Thanks,
Peter

[EdDee]

Hi Peter,

Glort's the man for WVO advice.... but.... in the interim, fuel it up, run it, if it looks like its starting to ail, a squirty bottle and a bit of water puffed down the snout while up to running temp to break any carbon free....

But let's wait for Glort to give a real answer!!

Cheers
Ed

[dax021]

Thanks Ed, will see what Glort has to say.  Also hoping the OP of the oil bath WI will jump in

[dax021]

Hi Glort, thanks for the info. 

Engine is in a shed, permanantly mounted running a 4Kw alternator @1500RPM.  I think the displacement is 1100cc, twin obviously.  I use it for standby power for when my solar can't cope or when welding, running a compressor, etc.  I had it serviced when I bought it and have since put on just over 200hrs without any problems.  I guess on average I run it about 5-10hrs a month.  I read your (or was it Ed's) comments about feeding a drip into the intake and watching the exhaust, but haven't quite figured out how, being a twin and the fact that the exhaust goes through the shed wall and then underground.  Maybe i'm overthinking the whole thing and should just run the WVO and squirt a litre or so of water down the intake once a month.

Thanks for the advice.
Peter     

[BruceM]

Mr X's had a very simple and effective system for WI that I liked. He used a shallow covered pan (I'm thinking Tupperware or similar) located just barely below the intake manifold, with a small tube and flattened brass end into the intake manifold.  No chance of disaster in failure, stops when engine stops.  The shallow pan with water just below the intake is to allow the minimal intake vacuum to do the job and provide relatively uniform rate of delivery. A needle valve or crimped brass tube in that small silicone (RC fuel line) line could restrict the water consumption rate.

The addition of methyl alcohol to the water to prevent freezing in winter was also discussed.  Glort reported methyl alcohol improves diesel power so that's a plus.

The additions I was thinking of making were to add a shut off valve controlled by engine temperature and a magnet-hall effect sensor to sense throttle position.  I'd keep WI off until engine was up to temperature and load was better than half load.  I've also pondered adding a float valve to the pan, making it quite small, and feeding the float valve from a larger gravity feed tank mounted on the wall.  The tank should last 8 hrs of run time, since I do a check over and oil service at that interval.  If the very small pan tank has an overflow tube that runs to a catch pail, a float valve fail will be of no concern. 

 I have some relatively low power very small 12V solenoids for low pressure that I could use. A snap switch could be use for head temperature sensing, it could feed the throttle arm magnet/hall effect or magnet-reed switch for a combined signal. A power transistor or DC solid state switch could then operate the solenoid.

My Listeroid does much of it's service in air compression so AC power isn't always present.

Glort, let me know if you think this is overkill for a remote start, unattended engine; I already have the controller shut down the engine if has no electrical or compressor load for 10 minutes.  I assumed that WI on a cold (just started) or unloaded engine would be a bad idea.  Getting rid of the throttle position sensing would make it much simpler, though it is certainly not too tough.

[BruceM]

Thanks for the helpful advice, Glort.  It's much appreciated.

A low power, 12V dispensing pump does have some merit- same controls as a solenoid valve and perhaps about the same current.  The supply could then be anywhere, and no float valve simplifies things too.

The smallest one I can find uses 300 ma at 12V. No doubt the water flow is excessive but I suppose I could run it off a cmos 555 timer can cut the duty cycle to 1 second in 10 or so.  I'll still have to rig a bypass for excess flow.

Maybe I'll find a better suited pump on ebay tomorrow AM.

[BruceM]

Good ideas for thought. I can see why petrol injectors would be appealing as a means of atomizing and metering for your oil burner design. 

I think small droplets are OK for WI in the intake manifold so a brass tube into manifold with venturi effect seems appealing; even with a micro DC pump it could be set up with a tee-bypass and crimped brass tube insert flow restriction so that water head is insufficient without intake manifold venturi/vacuum.  Silicone tubing would make that readily visible for adjustment.

I don't have AC power when doing a lot of air compressing; I like to unstrap the generator head as it does affect my fuel consumption.  So I'd like to keep my power use to the minimum.  I do have a little 40W panel and 12V battery (hand me down's from my no-alternator car that have lost too much capacity) in the engine shed, but I like to keep running power draw to a bare minimum. 

I'll take a look today at floor (pump) vs wall mount tanks (gravity) and see what seems easiest. 

[BruceM]

I checked out my engine room for water injection possibilities.  I think I'll try a covered shallow pan just below the intake manifold method developed by Mr X first.  There's a nice spot on the wall that I can add some brackets and a plastic storage bin as the feed tank.  I found the small solenoid valve in a parts box in the engine room, and even a needle valve so this could be a very cheap to build setup.  I've got to look at my thermal snap disc collection next.

edit- sorry, wrong video link here, will re- upload and update the link next.
Here's the on-topic video I meant to list:

https://youtu.be/AiMfoOW6CLw

[32 coupe]

Nice video, as always !


Gary

[BruceM]

Thanks Gary, Alas, I uploaded the wrong video- it was one showing my Listerioid setup but not the one I had intended for this thread. 

Because of the ease of implementing Mr X's intake venturi feed method as I discussed, I'm rounding up parts  to give it a try.

[BruceM]

It's Mr X's method as he reported here; a shallow pan with water level just below the intake manifold, feeding a pipe in the intake manifold. Intake suction pulses pull the water up the last inch in via venturi.  He flattened the end of the tube to get reduced flow and finer droplets.  I'll report on how it goes. I'll just be adding the solenoid valve and head temperature switch. 

[ajaffa1]

Very much looking forward to this, I love to learn new things from people with experience. More pics and videos PLEASE

Bob

[dax021]

Yes please, also looking forward some pictures.  I presume with a twin, one would just T the water line, one branch to each intake?

[BruceM]

You nailed it, Glort.  The CS intake vacuum is so limited that flow rate will vary with height above the water, and even a few inches will change the flow rate.  Mr X already proved this approach works using a shallow pan to reduce the variation, so I will pursue it further. The flow rate will also vary with restriction of air filter. I'm not sure what Mr X used, I have a paper filter and he may have used the stock oil bath.

That is the advantage of Glort's preferred metered, pressurized system; a consistent flow rate.  But I'd like to see how this intake venturi/vacuum method works out.  As you pointed out, Glort, a fairly wide range of WI is OK, and once set up if flow increases by 50% because the air filter is getting dirty, it should be fine. A reduced WI rate as supply is used up is also not a show stopper as long as the variation is not more than 75% for a useful volume of water.

Your rather brilliant and original idea of using an inverted bottle to maintain a constant level would completely eliminate the water level variance ... A two liter soda bottle inverted in a small container might be an easy to service WI supply with a totally constant water level.  A float valve filled small container would also do that and allow for a larger water supply.

I'll know more today after I test the intake vacuum and venturi flow rate variance. I want to try different tube diameters in the intake manifold to see if that affects suction. 

Glort or any other experienced WI users:  Could you provide a guesstimate of a range of water flow that you think would be appropriate for my Listeroid CS 6/1?  The minimum effective water flow rate to reduce carbon buildup using dino diesel would be particularly helpful. 

Dax021- yes, a tee should do a twin.  I'll try to collect vacuum and flow data today if the wind doesn't do me in. I'm still at the thinking and collecting data stage.  I will update as I progress.

[BruceM]

I measured the suction on the running CS 6/1 intake manifold at only 35 mm or 1 3/8 inches of water.   So the range of water that can be used without a flood on stopping is very shallow.  For the emitter in the intake manifold I used 3/16 OD brass tube with the end cut at 45 degrees facing away from the flow. 

https://youtu.be/LBIlMnNyCic

I see why Mr X flattened the end of his tube to restrict flow-  with the open tube, as you raise the water level (in my case raising a 10 ml syringe body attached to a telescoping stand), the flow is fairly brisk (>1 ml per second) until the water gets below the flow level and then it just stops. 

This tray feed method could certainly be used effectively as a batch WI process- get the engine warmed up and then fill up your tray; it is essentially gravity flow until the water level gets down to the stopping level of 35mm below the highest point of the manifold emitter. If you fill your tray above 35mm, you risk an intake flood if the engine should shut down.  The WI flow rate should vary linearly with water level.   

This is not what i had in mind for my use since my generator shed is quite remote and I'm more interested in something automatic that just needs water every 8 hrs of engine run time, with my usual runs of 40-60 minutes.
I'll need to add some complexity; a constant water level to be regulated via float valve or the upside down bottle method Glort suggested.  I can now fiddle on my bench with the manifold orifices  and needle valve to get the desired flow rate with a head of about 20mm of water.

If I use a 4 ml/minute flow,  8 hours of run time would use about  2 liters of water.  Is that sufficient? Would pulses of higher flow be better for dislodging deposits?