| well chit [message #278789] |
Sun, 31 May 2015 15:40  |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
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I had problems with the coach vapor locking at inopportune moments. Like in downtown Atlanta on I - 75 - 85 at 5 in the afternoon. So, when we got home I started in on (obviously) needed repairs/upgrades.
The hoses to the charcoal cannisters were toast, now replaced.
All the wires and hoses on the engine checked and ty-rapped out of harm's way.
Built up a piece of flat steel with two Mr Gasket fuel pumps and a relay, and cut and fitted it from the frame rail to the crossmember the front tank straps bolt to.
Now, the tank valve power pulls in the relay, whose SPDT contacts switch ignition 12V from the main to the aux pump, using the dash switch. Since these pumps draw ``2 amps running, and since I added a relay and a separate fused supply to the ViAir compressor, I used the ignition hot feed to the compressor. It now supplies one relay and one Mr Gasket pump at a time. I will be reducing its fuse to about 10 amps. I teed the output of the two pumps into the fuel feed line going frontwards to the mechanical pump and carb. The pumps have internal check valves,so the running pump will supply the carb. I'll be testing and road trying this setup tomorrow. Next step is to bypass the mechanical pump on the engine. I left a loop in the 12v pump line for a turnover switch. I propose to acquire the safety switch from an 05 - 09 Ranger, which resides on the passenger side firewall just above the toeboard in the pickups. It responds to a sharp blow as well as being 90 degrees or more off level. Way simpler than an oil pressure switch.
In the middle of all this, I am acquiring a Holley TBI system. When I install it, I'll simply remove the Mr Gasket low pressure pumps and duplicate the pump which comes with the system. Thus I'll still have two switched pumps and no valve. They will fit in place of the Mr Gasket ones, so no further plumbing will be required in the back of the coach. The Holley return if there is one) can be teed into the filler vent line.
I hope this cures the vapor lock problem.
--johnny
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
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