Water Injection and Piston noise question - page 1 - IDI Engine - VWDiesel.net The IDI, TDI, and mTDI source.

• Water Injection and Piston noise question by Solar_Subaru on 05 Apr, 2006 20:23
• Ok folks, this is my first night on this forum, so please be gentle.
  I am relatively new to diesels and VWs, but I have been running my 92 ecodiesel jetta (little tiny turbo) with the pump turned up, so I am running about 16 psi boost at full.  I also run biodiesel, WVO, and I have recently been running water injection, so here is my question.
  
  What would cause noise that soundes like piston slap when I inject water/methanol?
  My water/meth injection adds 3-4 psi at full boost and is ver addictive, but I am concerned about the noise it is making. Could the engine be detonating/preigniting? or is it just making more noise because it is working harder?
  I did a rather amaturish job of changing out the t-belt last time, could my injection pump timing be off, making my advance to high?
  
  -Tony
• #1 by hillfolk'r on 06 Apr, 2006 16:18
• man,,mine never did that what kind of setup do you have?,,maybe too much water???yea i use blue washer fluid,,,,
• #2 by Solar_Subaru on 06 Apr, 2006 17:58
• I have 1.6 with a mechanical pump. I am spraying water into the turbo, I am also using blue washer fluid.  I tried water/meth mix too, but it made the noise worse than with the washer fluid.  This lead me to believe that it was the meth that was making it preignite/detonate.
  Do you think I should go through the whole dial indicator thing to set the pump timing? to be honest, my fuel economy went down the crapper after I turned up the pump and changed the t-belt.
  
  -Tony
• #3 by firestorm13666 on 06 Apr, 2006 19:14
• Tell me if i read this wrong but you said you are injection what into the turbo meaning before or at the compresser housing.If so you have it set up wrong form what i know of water injection.I belive when i was looking into water injection the best place to put the injector is about 10 to 15 inchs before the TB but our diesels do not have a TB so i just put it about that far or maybe 20 inchs form the ports?Also if this is all true your noise that you are hearing could be form the turbo it's self form the heat shock you are giving it form the water,also you can not really compress water which is what you are doing.I hope this helps out and i am sure the others will chime in and tell me if i am wrong and help you out more then me.Later and good luck
• #4 by hillfolk'r on 06 Apr, 2006 20:58
• no that setup is ok, intake pipe is ok,i have mine about 6 inches from turbo inlet,,,"jet" it down some,,,toomuch water,,,its not thermal shock,,,,theturbo actually helps atomize that water like a mutha!!,,ithinkyou are shooting toomuchwater,,i never tried anything but washer fluid,it has meth in it too i thought,,actually,when i had mine "in development",,it stillwould shoot a stream like 5 feet,,,,,i didnt aim it at the turbowheel either,i aimed it at the side of the intake pipe a little too,hoping the water bouncing off,would be broken up better,,,,,,i shoved a old carb jet in the hose,before the actual spraying jet i used,,both are probably .040 or so,,was from my ol suzuki dirt bikes,,,,,mine was using an old a2 washer bottle,gallon,sweet,, also mine was activated by shifter button,,iactivated it at 3500 rpm or more,cause i was scared what would happen down low,,,,like hydrolock,,i ran mine like this for about 2 years,,,,,,,,ive got a few of those thick "how to" supercharge/turbocharge an engine,,,they say the pre turbo setup is acceptable,and works fine :wink:
• #5 by Solar_Subaru on 07 Apr, 2006 09:00
• Hey man,  It sounds like we have just about the same setup.  The washer does have a good amount of meth, but I ran a higher percentage of meth at one point, and I thought I was going to break something.  From what I have read on the Water Injection forums,  shooting water directly into the turbo is ok with a fine mist, it won't erode the compressor wheel this way, and that doing this actually makes the turbo almost perfectly thermally efficient!!, making a turbo act like one that is almost 25% larger, which makes sense, because, with no intercooler, I get about 3-4 psi higher with the washer injection at 15psi.
   My setup is very simple, but I did the same thing as you did with the placement of the jet, aiming at the inlet hose wall hoping it would atomise better.  I hooked my hose from the windshield washer bottle to a jet made by heating up and squashing the end of a 1/8 plastic tube.  Mine shot about 12 feet, I remember because I squirted my garage partner with it! HAHA!  I got really lucky with the jet sizing, this is how I know:
  1. Below 5psi boost, if I activate it it does nothing. If I hold it on, the engine will start to misfire, this is probably very bad, but it hasn't blown up, and now I know that it is too much.
  2. above 5, right up to 12psi, if I activate it there is a noticeable power increase (with the "detonation"noise), and the boost gage shoots up really fast.
  3. If I wait til I'm at full boost (16-17psi) to hit it, there is very little diffence in power, So either I'm running out of fuel at this point, or the water volume is not enough.
  I have some other issues as well, I have bubbles in my fuel line to the pump, so I might have small leak somewhere. From what I hear this can seriously affect power and mileage, and like I said before, I think my pump timing might be off.
  1. Is there a place on this forum that outlines the perfect pump and cam timing and the procedure for getting them?  
  2.Is my cam timing adjustable?
  3.Can these adjustments be optimized for economy/power?
  At one point I had the car pulling so hard without the water injection, that my NEW CLUTCH started slipping when the boost came up in third. But the rpms wouldn't drop back down after accelerating so I turned it back.  I think I saw the pump mod thread on here yesterday that might address this, I stumbled on most of those mods myself by messing around.
  
  What do I do now? :?
• #6 by LeeG on 07 Apr, 2006 13:04
• here is the best description of timing setting I have found here:
  http://www.vwdiesel.net/phpBB/viewtopic.php?t=3587
  about half way down, long post by wyldman
  
  The cam sprocket is on a taper with no key, sprocket needs to be loose on cam when setting belt timing.
• #7 by VentoTD on 07 Apr, 2006 14:26
• Isn't methanol very flammable? I think it detonates by compression, wich makes ugly sounds because the timing gets affected. Try using just water. I'm also spraying my turbo with a water jet from a window washer. Works nice.
• #8 by hillfolk'r on 07 Apr, 2006 21:55
• use blue washer fluid,,,mine shot like 12 feet also,with the one jet,,,i put the other restrictor in to cut it down,,,,,,water injection reduces egt's,,,its good for that,not necessarily more power,,but it will add some,,do this test,,,wheni was on the hiway,pulling up a grade,holding a steady speed,sayat like 70-75,,you will probably be pushing 8-10 psi at that point,,,,,now activate the injection,,see you haveta get out of the throttle,cause it accelerates,,drop off a few psi boost,,thats horsepower,not alot,but it proves it,,,,like isaid i realy didnt activate it till over 10 psi anyways,,i tried it at slower speeds once,and i felt it misfire,like it was toomuch,putting out the flame sorta,,,actually thats what i did,,90 deg plastic elbow,like washer bottle plumbing crap,,,jet in the end,sealed in with shrink wrap,dont wanna lose a jet,,,you haveta install a lift pump,,thatll give a little better throttle action+possibly power, ,,iuse one from a late model dodge ,the isb(cummins 6b) lift pump,,,
  1,,theres probably some info on checking timing on here ,,search,,,,,,,,2 yea sorta,the camgear isnt keyed to the cam,the tool requires feeler guages as shims,so games can be played there,although idont do it myself,,,,,,3   on my tdi-m,,,without touching anything igot between 51-54 mpg on a trip to ny state,and,i ran about 97(read,almost 100) in the backroad officialmeasured 1/4mile ,,,so when you are not in the throttle,it aint usin fuel,,,4 yea tellme about clutches,,,stockones wont hold up,,get a centerforce dualfriction,,,i got one,,but when its cold(engine temp) sometimes it wont hold in5th at wot so i may need to upgrade,,if im nice to it for about 25 minutes or so,it doesnt slip when warm,,,,im gonna get a paddle,screw it,,but a centerforce on a 1.6 is ok,,,i originally had this clutch on mine,,and it only had like 8k on it,,,maybe iwas a little too easy on it from break in,,ill see,,,i prettymuch left my timing towards the max end of stock,right around 1.00,maybe 1.05 or so,,im sure theres someone knows whats up with that too,,this site has alot of dudes that know good vw stuff,and share it too,,realcool place to hang out
• #9 by Solar_Subaru on 10 Apr, 2006 06:30
• I installed a six-puck bronze clutch, it has been a pain to learn how to drive it in traffic, but it seems to hold well.
  On a long uphill pull on the highway,  I don't need to push the pedal down anymore, I just pull the squirter switch, and it climbs without extra throttle.
  I have no doubt about the Horsepower, it is definately there!
  I'll check out the thread on pump timing.
  Thanks
  -Tony
• #10 by fspGTD on 10 Apr, 2006 09:59
• Hey guys, thanks for posting about your experiences with water/alcohol injection.  And Solar_subaru, welcome to the board!
  
  I have a request: would you try injecting pure water (no alcohol) and see if by itself, it makes a change in boost pressure and/or power?  I'm very curious about this because my racing class allows water injection, but does not allow using alcohol.
  
  Also, do you have any worries that the blue dye or soap (assuming there is some inside the windshield washer fluid) will accumulate in your combustion chambers?
  
  Edit: moved to IDI Diesel (power enhancement) section
• #11 by wyldman on 10 Apr, 2006 11:32
• Water only will not make power,only help reduce EGT's and IAT's,and allow you to run more fuel and make more power without detonation.
  
  It's the meth that makes the power.The stronger the meth concentration the bigger the gain.Boost pressures,timing,and RPM must be right for optimal power gains.
  
  Injection should be delayed until at least 7-8 pounds of boost.You also need a fairly high pressure pump.A winshield washer pump won't cut it.
  
  You can also make it two stage,if your running big boost numbers,to minimize low RPM problems,yet still get the max benefit at higher RPM\boost levels.
  
  The blue is just a dye,and it's concentration is less than .05%,it won't harm anything.
  
  If you want to use just water injection for racing,then you can set the engine up with more boost\fuel,and use the water to keep it cooler.It will allow more power to be produced,with reduced EGT's.
• #12 by Solar_Subaru on 10 Apr, 2006 13:31
• I found that water alone does make about 1.5 psi extra boost at about 15 psi, just enough to notice a light increase in acceleration. But this is only when injected into the turbo inlet.  What I was told on the water injection forums, is that it makes the turbo more thermally efficient, making a compressor up to 25% more efficient. As wyldman already said, my engine doesn't heat up when under long periods of boost. In a gas motor, this will allow you to run higher compression ratios, lower octane fuel, or a higher spark advance curve. I would guess you could do the same with injection pump timing on a diesel?
  personally I am starting to think that when squirting into the turbo, you really don't need the higher pressure pump, except maybe for better atomisation of the water to avoid hard impact on the compressor blades.
  I imagine longevity of the washer pump will be an issue if I continue to run it this way.  But for a quick rigged system, that didn't cost anything (YET) this system hjas been very effective, to gain 4 psi using what the car already has!
  
  I also know guys on gassers that just run a venturi style water injection, with a boost line to the water resevior so the injection pressure increases with boost. I really don't know how effective this is though.
  Thanks for the welcome!
• #13 by fspGTD on 10 Apr, 2006 13:44
• Wyldman: As I understand it, water injection can increase cylinder pressures in the power stroke (and therefore, power and torque) if the water droplets are not completely vaporized before the intake valve closes.  If some of them evaporate and expand during combustion, it could possibly increase the expansion of the mixture.  Although I agree that if injected before the compressor and given a lot of time and distance to travel in the intake tract, that it would be more likely that all the droplets vaporize.  While this would give more cooling of the intake air temps, it would possibly not give the possibly power increase, so I am still interested in hearing from someone who has tried it in a VW Diesel (either pre- or post-compressor.)
  
  Edit - Solar_Subaru, just saw your response... very cool to hear you have tried pure water injection, and that is very interesting that you've found a 1.5 psi boost pressure increase and accompanying (albeit slight) power increase.
• #14 by wyldman on 10 Apr, 2006 14:03
• Normally your injection is done post turbo,so you need a good pump to overcome boost pressure.It also has to be well pressurized for proper atomization.
  
  I haven't found any benefit of adding pump timing with the water or meth.Optimal timing seems to be the same.
  
  Most of the water\meth injection I have done is on bigger high HP diesels,mostly 6BT's and ISB's well over 500HP.I tell you,you can gain some serious HP on those setups.You need a 200 PSI pump though.