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View Full Version : Fuel-Tank & Pick-up issue ?



silverghost
02-19-2011, 04:19 PM
The very last time we used our 24' American Skier Eagle Skiboat we had an engine fuel starvation issue. The engine was running out of fuel and stalling.
I was later able to later trace this problem to the top of my fuel tank & it's pick-up !
The tank pick-up fittings
were made of Aluminum that was heaviy corroded and turning to dust.
My fuel pump was sucking in air as a result !

Background:
The 47 gallon custom shaped aft fuel-tank is made of 5/16" thick cross-linked sem-clear Polyethelene.
It is located under the boat's rear sun-pad & storage area.

The old tank pick-up consisted of a 3/8" 90* aluminum pipe elbow with a plastic tube glued into the male threaded end of the tank elbow.
This tube then goes from that 90* elbow to the tank bottom where it is cut on a 45* angle. There is no pick-up screen on the end of this tube at all.
The Aluminum elbow & pick-up assembly was threaded into an Aluminum bushing bung molded into the fuel tank !
It too was heavily corroded !

When trying to remove this heavily corroded pick-up 90* elbow it literally crumbled to corroded aluminum dust !

I now need to fabricate a new pick-up assembly out of better materials for the marine environment !

The other bigger issue I now have is with the threaded bushing in the top of the Poly tank itself.
This 3/8" female pipe bushng was made out of the very same cheap aluminum and has turned to corroded dust also.
Most of this bushing came out of the top of the Poly gas-tank with the aluminum pick-up elbow !
Now I have no threads in the tank at all to install a new pick-up elbow !

My questions to the Forum members~~~

1) How should I fabricate a new & better pick-up elbow & tube assembly ?
Should I include a filter screen ?

2) How do I get a new threaded 3/8" female pipe bushing in the top of my old Poly tank ?
The hole now remaining in the tank itself is now smooth without any remaining threads and is now oversize!
I now need to somehow install a new threaded bung fitting in the top of my Poly tank !

3) Should I install some new sort of anti-syphon valve that I see in the fuel tank parts section of the West Marie Catalog.
This new valve is supposedly Coast Guard required on all new inboard tank applications according to West Marine!
Will this valve be of any real safety benefit?
Will it restrict any fuel flow to my Big Block Chevy HP 500 ski-boat engine ?

Any ideas or help greatly appreciated !
Thank's

Brad Hunter
215 947 4676
silverghost1926@msn.com

MOP
02-19-2011, 04:45 PM
Is there enough meat left to re-tap to 1/2" ?

silverghost
02-19-2011, 05:03 PM
There would not be very much left to thread a 1/2" pipe bushing fitting into the tank top.
The tank is only 5/16" thick~~~at best !
Where the old threaded 3/8" bung was originally molded into the tank it is only slightly thicker~~~
Going to 1/2" pipe bushing thread size would remove all of this old thicker bung fitting portion !
There would only be 1-2 course pipe threads in the tank's poly plastic top !
There would not be very much holding the new 1/2" bushng in place there !
I don't know of ANY glue or epoxy that would stick to Poly that could be used to "Build-Up" this thickness in this area ?

Ed Donnelly
02-19-2011, 05:41 PM
When I go to the shop on Monday, I will get the name of the stuff we used to build up a plastic tank to drill and tap a 1/2" nipple .......Ed