Diesel backfire = too much W/M???

[gear jammer 91"]

I installed a second squirter on my w/m setup tonight. The first squirter is 14gph and the second is 10. I'm runnin a 50/50 mix of w/m and its commin on at 10psi. The first two full throttle pulls I did were in 4th gear and everything was great, lots of power nothin to worry about. The second pull was from a stop, when I hit third about half way through the gear it popped so I backed out of it and stopped to do a visual, all ok. I took about half throttle got into third and backfired twice and blew a bunch of smoke. It runs fine with it off, did I just go too big? Thanks for all the help, sorry about the book.

[Begle1]

I didn't know it could backfire. I thought it would just preignite and result in detonation damage?

Mmmmm, you're a manual. Maybe when you are taking your foot off the pedal in between shifts, the solenoids aren't closing with the boost drop... Causing the pump to flood the intake really rich for a second and a subsequent "backfire". Maybe?

[gear jammer 91"]

I think you may have been partially right Begle, about the solenoid not closing. When I shift if I'm runnin it hard the boost falls off but not fast enough, it was staying above the pressure that engages the w/m for a split second with little or no throttle in between gears. I upped the engagement pressure to 15psi from the 8-10psi it was at, and I also changed my second squirter from a 10gph to a 5gph just to be safe. I've made a couple full throttle runs up through the gears now with no issue's and a couple part throttle runs also with no issue's. Do you know, if I'm runnin straight water just for cooling what would happen if I used too much? When I turn the fuel pressure up all the way she gets really hot, and the reason I got the w/m was to take care of that. Thanks again.

[Begle1]

Too much water will bog down the engine. Way too much water will hydrolock the engine, which may bend rods.

[CumminsPride]

Doesn't also increase the cylinder pressure due to the water having mass?

[Begle1]

There seems to be a few different theories regarding what water injection actually does.

Water vapor shouldn't drastically increase pressures, since a gaseous water molecule is the same as an oxygen or nitrogen air molecule.

Liquid water doesn't compress and drastically increases your compression ratio.

BUT, water fumigation for gassers is advertised as "letting you run a lower-octane fuel without detonation". I don't get how that works.

I guess that the water cools charge air, resulting in denser air at a lower temperature. It's temperature and not pressure that results in detonation. So water gives a lower temperature throughout the entire compression stroke, but it gives a higher pressure at the same time. Liquid water gives lots more pressure, but the water may still keep temperatures low enough so that you don't see detonation.

I thought about it a lot a while ago, and it kind of came down to that no matter what your level of understanding is, there are enough unknown variables that your going to end up doing things through trial-and-error test-and-tune anyways...

[GLHS]

You have it set too low.
Minimum before engaging should be 20+ in my opinion.
If you only make 20 psi of boost you could turn it on that soon. If your making 40-50 I would set to at least 25.

[gear jammer 91"]

My max boost varies by gear. It starts at about 15psi max in second and climbs to a little over 30psi in fifth. I ran the w/m for about a month and a half with the single 14gph squirter set around 10psi with no issue's but I guess that was because I wasn't pushin enough w/m. The 15psi I have it set at now seems to be good so far.

I think I might have created a bigger problem. There is just the slightest little amount of a white milky substance on the end of my dipstick. (Not that dipstick ) Once it cools down outside I'm gonna drain the oil and see if I have coolant in it. The radiator doesn't have any oil in it. So does anybody know what could cause that, besides a blown head gasket or a cracked head ?

[PToombs]

I think that's a by-product of running the w/m. I've heard other guys say their oil gets milky if they use it alot. Like out playing around at nite, using it alot for 2-3 hours, something like that. Once or twice a day didn't seem to bother at all.

[gear jammer 91"]

Thats what I am startin to think. I drained the oil last night and there was no trace of water in it, and the new oil doesn't show any sign's of water either. The radiator was also clear of oil. I think I'm safe.

[fergavs]

I did the exact sqame thing just before I tore the motor down this last time. I had been using the w/m for a long time (aprox 1 year) but didnt use it a lot because at higher rpm it kinda made the motor "crackle". Well after doing a tune up and adding as much timing as possible I took the truck for a test run and under full throttle/high boost flicked on the w/m. There was a terrible bang,bang,bang before I could let off. I popped the head gasket and decided to tear the motor down and do a bunch of stuff. Anyway I called Snow and asked why my w/m would be doing this. They instantly replied you have the nozzels installed backwards. I said no way I was sure I had double checked. The tech disagreed politely and said he was positive that was the problem. I asked why had it took so long to cause a problem? He said because of the heavy over fueling it probably was able to accept most of the water but with the extra timing.....POP!!! So is it posssible your other nozzel had been installed backwards? I was sure mine werent but when I checked they were. Now I have a very nice mist vs a very bad squirt.

Sorry for the short story.

[Begle1]

Nozzle installed backwards? I guess I've never seen the real "nozzles" that they use...


Methanol or propane don't mix with highly advanced timing, that's a recipe for headgaskets if not bent rods.

[gear jammer 91"]

the nozzles I have are not capable of being installed backwards, I allready double checked just to make sure. The kit I got is from a company called devils own and the squirter's they use are different than the ones everybody else uses.

It popped/backfired again. This time I was in third, no shifting just a full throttle burst. I'm gonna drain my w/m tank and run straight water to see if it's boggin the motor cause it's gettin too much w/m and not enough diesel, or what its doin. My fuel screw is backed out quite a ways for mileage, I can barely hit 1200 wide open in fifth right now so it could be gettin too little diesel. Who needs good mileage anyway.

[gear jammer 91"]

"the nozzles I have are not capable of being installed backwards"

Please completely disregard this comment as I did in fact have both nozzles installed backwards. Once I pulled my head out of my arse I was able to figure that out.

Thanks fergavs I never would of figured that one out on my own.

[Begle1]

Could you post pictures or explain what these nozzles even look like?

How does having a non-atomized spray result in backfire?