So, I switched to E85 last fall, drove it for a while and all was fine. I had my alky turned off the whole time, and kept it full so i could use it for mapswitching in case i ever needed to fill up on gasoline.

I switched back to pump gas about a month ago, and the car runs perfect on my old tune, except for the Aquamist HFS-1. First pull, it flows what it should, then teeters off up top. Any pull after that, I get 4/8 bars of flow, and AFR's are 1 point higher on the wideband. I use 50/50 meth/water, 1.0mm jet. Normally I see 6 or 7 out of 8 bars on the flow meter when it is operating correctly. I checked for leaks around the on/off valve, flow sensor, and at the point of injection. I swapped out the nozzle with a .9mm jet, and got consistently only 2 bars out of 8.

I haven't ripped apart the trunk yet to see if there's anythign leaking back there, but I haven't seen any drippage or excessive loss of fluid.

I think it is temperature related, because I was on the dyno recently, and the temps in the dyno bay were ~60-70 degrees F, while normally the car is outside, it is much much colder, anywhere from -10 to +30F. While on the dyno, I got the normal amount of flow I'd expect, right around 6 or 7 bars.

I've 'solved' the power loss associated with this problem (i.e. just running w/o alky, straight pump gas) by installing a BBK , but for some strange reason I have the urge to turn the alky back on and boost back up

Any ideas?

 

have you cleaned out the filter by the pump?

 

no...brilliant!

But how would this be temp related? Perhaps water freezing in there or something?

 

Someone in Canada reported the same, when the temperture went down to -40C.

As soon as the car went into a garage overnight, it start to flow normal again. We think it has something to do with the viscosity.

Chart shows the viscosity doubles between 25 deg.C and 0 deg.C

 

Checking the filter is a good idea.
You already swapped out nozzles so its not a clogged nozzle.

I'm just guessing now - does water's viscosity change with temp?

 

Arggg... Richard you beat me to it...so it is realated to viscosity change with temp.

Any way to calculate the viscosity of water when mixed with meth 50/50?

 

I found this chart by google.

Abner has posted a viscosity formula some time ago. I can seem to find it at the moment.

 

Hrm well it'll be extra warm here tomorrow and friday, I'll have to flip it on and see what happens! 45F woot!

 

Ok so on the days where its colder, I get 4/8 bars consistently. When its warmer than 32' F, I get 5 bars. When I was on the dyno, the bay was about 60'F, and I got 6/8 or 7/8 bars, as I would expect.

Last night I pulled the tank/pump assembly out and examined it. All looked fine, took apart the filter and it is nice and clean, and no signs of any leaks, anywhere.

I installed the kit last March, and if I think back it was probably fairly warm the whole time, maybe like 35+. Not sure what to do next.

 

When a nozzle is spefied for oil, it flows differently for water. The viscosity may have something to do with it.

If you still have a cold days left, perhaps you can made a one-minute test with your spare nozzle onto a measuring glass. and repeat the same test on a warmer day.

If I have time I will freeze a gallon of water/methnol overnight and run some tests. I want to find out the mystery soon so that I can design some counter mearure if there is a drop in flow or just reading lower by the flow sensor.

 

IDK, there's several other aquamist kits running around MN, I haven't heard any of them report this problem. I could switch back to 100% meth I guess....

 

* and they're all running 50/50 that I know of.

 

Well sure enough, its 50'F here today and I get a solid 6 bars of flow. At least I can be happy for a while

 

how could it evaporate/disperse with a sealed cap? I think a leak is depleting your fluids

 

Nope. The tank was 100% full the entire time, I never topped it off. I had some issues with leaks last summer and had replaced the tank and re-sealed everything.