John, My FI fuel pump is the new style with only two ports so there's no way the gas can back into the tank from it.
Bruce On Sat, Jul 28, 2012 at 7:18 AM, John Palumbo <[email protected]> wrote: > Just a quick thought, I would tend to think it would have something to do > with the fuel delivery from the fuel pump. The fuel it would seem is > getting pumped back into the tank, instead of to the pump where it belongs, > hense you noticed it took longer for the pressure light to go out. > > If I can recall, the older pumps had three ports on them, one to the SPICA > pump, one as a return to the tank, and I think the third was for some > emmissions thing, I'm not sure. I know the the newer pumps had only two > ports. > > So maybe if you had a spare pump, you could try installing it and see if > it does the same thing. Perhaps there is a sort of check valve system, > similiar to that of a diode thats gone bad, it being that alows the fuel to > flow in only one direction, to the SPICA pump. The other thought would be > to run it with the fuel cap off. But there should be no logical reason why > the tank should be over pressurizing. > > John > > T-Mobile, America's First Nationwide 4G Network > Sent by Samsung Mobile > > Bruce Giller <[email protected]> wrote: > > >Yesterday we (David Tallerico and I) attended a Seat Time session at > Summit > >Point track after a too-long hiatus. The weather temp wasn't hot but > >pretty warm - mid to upper 80's or so. It is 1.5 hour drive from my house > >there and we stopped in Charles Town for gas. at around 7:50 am. At the > >station the car would not restart and we discovered that it was getting > any > >gas for the plugs were dry. The fuel pressure light went out but it took > >longer than usual for it to go out; usually after running for a bit, it > >only takes 1 second for it to wink out. I removed the return hose from > the > >SPICA pump and gas was pumped out with the fuel pump on. We 'fixed' the > >non-starting problem with starter fluid sprayed down the throats. Off to > >the track! > > > >Barely into my first session of the day, I started getting a whiff of > >gasoline but I attributed it to all the other cars whizzing past me. But > >then it got stronger and stronger which lead me to pull into the pits > >before I caught on fire. On the false grid, I stopped and opened the hood > >- no smell there. But in the trunk, there was a light layer of gas in the > >fuel gauge sender and a light coating over portions of the tank. When I > >loosened the filler cap, I could hear air escaping at more than normal > >pressure. And the car would not restart. I removed the air cleaner but > >this time it started without the need of the starter fluid. And replacing > >the air cleaner did not kill the engine. Gas supply related, perhaps? > > > >On the next session I withstood the fumes until they started bothering my > >eyes, so I exited the track and drove the car to our spot. This time gas > >was dripping from the front of the tank as well as being on the fuel gauge > >sender. The drip was not coming the lower exit to the fuel pump but up > top > >where the SPICA fuel return hose is connecterd to the tank. My flashlight > >turned out to be dead so I couldn't see if it was really coming from that > >connection. Once again the tank was pressurized far more than normal. I > >removed the fuel vapor recovery container and found it to contain a > >considerable amount of fuel - so much so that it when held level it poured > >out the two lower outlets (one drains condensed fuel back into the tank, > >the other allows vapor into the container). I drained the fuel back into > >the tank. The return fuel line did not show any evidence of cracks at the > >end and I tightened the clamp a bit more than normal when I put it back > on. > > > >I reasoned that the fuel in the vapor container was blocking the outlets > >and thus leading to over pressurizing the tank; and the fuel was > >an accumulation over many years. The two hose connections to the tank > were > >clear as well as the vacuum line back to the engine. And the air breather > >on the vacuum line allowed in and out - I don't think that it is designed > >like the later models that had a check valve to allow air in but not out. > > > >On the next session (tank was about 1/2 full by now - should have started > >with 1/2 tank), I ran the full 20 minutes and didn't smell gas (well, at > >least not nearly as much as previous session). Back at our spot, I > checked > >the trunk and I could hear air loudly hissing from the filler cap (tightly > >screwed on) and from the vapor container's air breather. I could hear > >gurgling sounds from inside the tank. And when I started to pull the > >filler cap from the tank neck, fuel & air spurted out of the filler all > the > >way up my arm and partially on my face - fortunately I was standing to the > >side and didn't get sprayed full on. I screwed the cap partially back on > >to let the pressure escape. After the tank was depressurized, I > discovered > >that the vapor container remained pressurized. There was even more gas in > >the container than previous which I drained back into the tank once the > >pressure was released. > > > >We left before the last session. At the end of the 1.5 hour trip back > >home, I cracked open the filler cap and found no pressurization. Tank had > >about 2-3 gallons left in it. The temps in the DC area where much warmer > >than at Summit Point and the traffic much slower. > > > >So just how is the tank getting so over pressurized?? Outside source?? > My > >rear muffler is not too close to the tank for there is the standard 3"-4" > >gap between them. The gas tank was warm to the touch when over > pressurized > >but not frying pan hot. I did replace the front resonator with a straight > >pipe but that shouldn't heat up the rest of the system that much. And how > >could it heat up almost 11 gallons of fuel so quickly on the track to > cause > >the pressurization? > > > >And how could the normal operation of the fuel pump system lead to > >producing this much pressure ? It is a closed system but with a vent to > >the outside via the vapor recovery container's air breather. If the > system > >is in working order on the car, the pressure built up so rapidly as to > >overwhelm the air breather's venting capacity and then the high pressure > in > >the tank forced gas up into the canister which in turn covered the two > >lower outlets aggravating the problem in the tank. > > > >All in all, very odd and disconcerting. It will be hard to replicate the > >problem in the driveway since it only seems to happen the car is driven > >hard on the track. > > > >Any ideas where I should look ?? > > > >Thanks, > > Bruce > > > >'73 GTV > >-- > >to be removed from alfa, see http://www.digest.net/bin/digest-subs.cgi > >or email "unsubscribe alfa" to [email protected] -- to be removed from alfa, see http://www.digest.net/bin/digest-subs.cgi or email "unsubscribe alfa" to [email protected]
