95+ Degree Weather Draining Tank?

[GNBeswick]

So I went to start my car yesterday....cranked it as usual and it caught....but right after, it died. So I cranked it again and it caught, but was almost dead, barely firing the cylinders. So I gave it a little gas and it smoothed out fine. Car drove just like normal, perfectly fine. Went to start it after work. Did the same thing, cranked, caught, than died. Than it wouldnt start...just kept cranking. So I gave it some gas while starting. Started up....was slow at first, than the rpms shot way up and it idled really high for 20 seconds than went down. Got home and unplugged the ecm, waited 15 seconds and plugged it back in. Tried to start the car and it kept cranking about 5-6 seconds....than it fired and idled perfect. Shut it off....waited a minute, tried again and it fired right up after a crank or two. Waited 45 minutes and tried it again, fired right up. No codes on the Scanmaster, everything seems fine. Tried it again when I left for work, fired right up. But after 8 hours in the hot hot weather again, it was back to its old ways.

Checked my alky tank and it was all but drained. Last night it was 1/8 full maybe a little under. Didnt boost at all today and the alky system was off. Have no idea where it went....but my car was sitting out in 97 degree weather.

I was told the heat may be pressurizing the system some how and sucking alky into the up pipe. I guess this has happened before? Is there a fix to this at all?

 

[bmackinnon]

Hey guys, I think he's verified that it's losing alky while sitting in the sun all day... and becomes hard to start. Starts fine if it sits all nite (in the cool). See his 'hard start' thread in the general section:
http://www.turbobuick.com/forums/general-turbo-buick-tech/251002-hard-startup-new-post.html
I know I've read about this phenomena (tank pressurizing or siphoning in the heat) happening to you alky guys... just can't remember the specific check/fix... Isn't the tank vented (or supposed to be?)... or maybe a check valve needs to be installed somewhere?, or the tank is mounted too high??? or??? I pointed him here....

 

[Chuck Leeper]

Easy check... Unhook the alky, and see if it continues??
Scan tool readings?
F press?
Starting off the F Pump bypass circuit?
Leaky injs?
"Giving it gas" putting it into clear flood mode?

 

[bmackinnon]

He had the system off. The tank level is lowering after sitting in the sun all day, and then it's hard to start. Added alky at nite, marked level, started fine in morning, drove to work with system off, sat in sun all day, hard to start, alky empty.... I KNOW I've read about this here..... anyone???

 

[Razor]

Heat is not the problem. Nozzle location can be. If the height of the nozzle is lower than the liquid.. it can siphon into the motor. This is why nozzles are placed high up on the pipes.

95 degree's is Winter in Florida :wink:

 

[GNBeswick]

Well I am sure that the nozzle is higher than the alcohol level. My alky tank is now bone dry after sitting in the sun today. I opened the tank and it gave a quick hiss....so I know it was sealed pretty good. We'll see how the car starts tomorrow with no alky in the tank.
So is there any fix to this? To keep the alky from draining? Cause the alky doesnt drain at all when its not hot out....even in 80 degree weather its fine.

You can see the alky nozzle placement here:

 

[bmackinnon]

Well I am sure that the nozzle is higher than the alcohol level. My alky tank is now bone dry after sitting in the sun today. I opened the tank and it gave a quick hiss....so I know it was sealed pretty good. We'll see how the car starts tomorrow with no alky in the tank.
So is there any fix to this? To keep the alky from draining? Cause the alky doesnt drain at all when its not hot out....even in 80 degree weather its fine.

You can see the alky nozzle placement here:

Sounds to me like you just uncovered the problem yourself. "Hissing/sealed pretty good?" That lid to your alky tank should be vented. It's building pressure in the heat, and forcing alky thru the hose. If you fill it up hot, and run it a bunch (using alot of alky), I bet it will build a vacuum in the tank as well, causing less than good or possibly no flow, and/or collapsing (imploding) the tank from negative pressure. I would drill a small vent hole in the lid of the tank and see if that fixes it. I read up, and there's also an anti-siphon valve you can install in the line too, but with the vented cap, I doubt you'll need it. Give it a shot!

 

[GNBeswick]

Will do; I've just been using the cap that came with the alky kit. I have the old cap to the water overflow that has a vent in it. I thought about using it once....but wasnt sure if that would allow the alcohol to evaporate? Maybe thats a stupid thought, but I'm not %100 on the properties of methanol.

 

[Chuck Leeper]

I meant to

He had the system off. The tank level is lowering after sitting in the sun all day, and then it's hard to start. Added alky at nite, marked level, started fine in morning, drove to work with system off, sat in sun all day, hard to start, alky empty.... I KNOW I've read about this here..... anyone???

UNHOOK the line to the nozzle...

 

[Razor]

Well I am sure that the nozzle is higher than the alcohol level. My alky tank is now bone dry after sitting in the sun today. I opened the tank and it gave a quick hiss....so I know it was sealed pretty good. We'll see how the car starts tomorrow with no alky in the tank.
So is there any fix to this? To keep the alky from draining? Cause the alky doesnt drain at all when its not hot out....even in 80 degree weather its fine.

You can see the alky nozzle placement here:

A picture is worth a 1000 thousand words. Your problem is the cap on the tank is not vented.. It is not the cap I sell with the kit.

No wonder your having problems :wink:

 

[GNBeswick]

Errr......well thats the cap that came with the kit I got from you Razor. The kit is from around 2004 if that makes any difference. But I am positive it's the one that came with it, because I remember thinking it not having a vent might have something to do with methanol evaporating.

 

[Razor]

You need to get the cap changed. See I buy those caps and grind them down, drill a hole.. and mount the vent. Try an OEM cap with the cardboard insert. See if the problem your having goes away... if so.. then just buy a new cap with the vent.

I dont even remember what I did in 2004 That year came and went