For enthusiast of the Classic GMC Motorhome built from 1973 to 1978. A web-based mirror of the GMCnet mailing list.

Home » GMC » GMCnet » Note for those with fueling issues (like Rod & John)
Note for those with fueling issues (like Rod & John) [message #326794] Wed, 06 December 2017 08:36
Matt Colie is currently offline  Matt Colie   United States
Messages: 6474
Registered: March 2007
Location: S.E. Michigan
Karma: 32
Senior Member
For Rod, John and others.

My coach was a real bear to fuel for the first few seasons. Then I did a CFD of the fuel system to try to optimize the fix I intended to only to find out that it probably would not solve the problem. What the study did do was point me at the real issue which was that the head in the main (rear) tank would shut off the fill vent of the front (auxiliary) tank. The study suggested a workable solution that has served me well.

Look up - Recommending High T, 29 July 2012 21:06
If you use the forum search for -recommending high T - you will find it.

Summary: If you separate the fill vents at the T that is in the area of the auxiliary tank fill and run separate lines up to just under the cab floor and join the vent there, you will be capable of fueling from near dry to FULL in less than 7 minutes. This can be done without having the tanks down. You will have to be able to get under then coach and also remove the left wheel well liner. One does have to stand by and listen. When fueling that fast, the nozzle will burp at the end, so listen and slow it down. You can still put in that last 5+ gallons safely.


Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
Previous Topic: Leigh Harrison Brake Rotor
Next Topic: [GMCnet] Replacing Batteries
Goto Forum:

Current Time: Sun Dec 17 04:10:24 CST 2017

Total time taken to generate the page: 0.14027 seconds