377 small block chevy, dual 425s, many issues?

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broflow
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Re: 377 small block chevy, dual 425s, many issues?

Post by broflow » Thu Sep 27, 2018 5:25 pm

The tanks are mounted with brackets that orientate them with the top up. In looking at the cut-away picture I wonder if the bent pick-up tube has rotated or possibly come off? I assume I'll have to take the fill/outlet valve off the tank and that the pick up tube slides in under it?

What I don't understand is if it's picking up vapor only why would the line be frosting up? Doesn't the cooling action come from the change of state from liquid to a gas?

Another thing that I've observed since getting this running is when I turn the engine off there is a sound from the rear of the truck where the tanks are that I can only describe as the l.p. is leaking past the electric shut-off back into the tank? I have the electric shut-off mounted immediately after the tank. Is this correct or should it be up under the hood?

BigBlockMopar
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Re: 377 small block chevy, dual 425s, many issues?

Post by BigBlockMopar » Thu Sep 27, 2018 6:29 pm

Tanks should have electric lock-offs and and use one-way valved T-connections to prevent overpressurizing neighboring tanks due to heat and pressure differences.
Just in front of the vaporiser there's also a lock-off valve supposed to be installed (overhere at least).
Both (all) valves should electrically close through a timed-relay a few seconds after the engine has stalled for some reason.
The relay takes its 'live'-feed from a sparkplug wire. As long as there are sparks delivered to the (running) engine, the relay will keep the lock-off valves powered up and open.
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Re: 377 small block chevy, dual 425s, many issues?

Post by C3H8 » Sat Sep 29, 2018 11:46 pm

Forklift tanks come in two styles. Some older versions could only be used in a vertical position. Later the dip tube location orientation was made so they could be vertical or horizontal provided they were rotated to the correct position. One other item to keep in consideration is that forklift tanks have excess flows in them. If you run out of fuel and swap or choose a second tank already installed you have to remember to turn the valve on slowly. Open it too fast and the excess flow valve will close. Enough fuel will still get past through the pressure equalizing hole to run/idle the engine but that is all. When this happens just close the valve, wait a few seconds and slowly crack the valve wait a few seconds more and then open the valve slowly.

broflow
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Joined: Mon Jul 24, 2017 8:42 pm

Re: 377 small block chevy, dual 425s, many issues?

Post by broflow » Thu Oct 04, 2018 1:17 pm

good info on the excess flow valve. I will open the valve slower from now on, that could be it? I haven't had time to find out yet.

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