Truck died when switching tanks

[Jims86]

Unless somebody was under there prior to your discovery, I dont have an answer for you. I have not dealt with too many dual tank setups.
But, what I do to cure it, is add a fuel reservoir( welded 5x5x5" box with barbed fittings) that was mounted after and fed by the selector valve, and ahead of that would be an inline pump. The in tank pumps would be used as lift pumps.
the reservior has 3 fittings, one for feed from the Tank, one outlet to the new primary pump, and one fitting at the top, which I would T into the oem return line.
SAE J30R9 fuel line recommended.

 

[towjoe]

Thats a pretty kool idea. Only thing is wouldn't the return line suck air? or you think in tank pumps would provide plenty of fuel so it wouldn't?

 

[chengny]

Per towjoe:

I've seen this problem more in more than one truck that has fuel injection.

That is a key point.

When the discussion involves an injected engine (with active fuel return lines), it changes everything.

I have to learn to check the model year for the "87" designation - especially in this (engine & performance) sub-forum.

 

[Jims86]

Thats a pretty kool idea. Only thing is wouldn't the return line suck air? or you think in tank pumps would provide plenty of fuel so it wouldn't?

Dammit, I thought I replied to this earlier.
No, the return lines wont suck anything. The T to the return line from the res, is just there incase the capacity is exceeded. It is best to think of the feed and return lines as two entirely different animals.
The pumps in the tank are the same as the in line pump, just add the barbed fittings....again, the objective is to maintain pressure to the TBI while the fuel tank switching takes place.