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Latest problem...vaporlock...perhaps [message #220715] Sat, 31 August 2013 21:38 Go to previous message
kerry pinkerton is currently offline  kerry pinkerton   United States
Messages: 2565
Registered: July 2012
Location: Harvest, Al
Karma:
Senior Member

Rob Mueller and I were out in our coach. 93 degrees and sunny.

Gas tanks about 1/4 full. Drove up the highway about 5 miles and stopped at a hardware store for about 5 minutes. As we were pulling out, the coach dies. Rob immediately said 'vaporlock'. My first experience.

Coach started right up and as we got back on the highway, I switched to the aux tank which has an electric fuel pump. A couple mile further I stopped and filled up with our local crapanol (10% blend). We then proceeded about 7 miles into Huntsville and stopped at Home Depot for about 10 minutes.

Rob drove the coach the 10 miles home on the electric fuel pump. About 2 miles into the trip the coach started loosing power at about 2500 rpm. Below that it ran fine. Above that it would just buck and loose power.

Eased on home. The fuel pump is running and I can kind of feel the solenoid engaging, although it is not as hard a 'click' as I would expect.

I called Emery and he mentioned that he's know for these solenoids not to fully engage.

I would have thought that the 25 gallons of gas I put in it would have cooled down things for quite some time??? One further note is that when we stopped for gas, there was a pretty significant overpressure in the tanks. Finally, when we got back home, there was a little overpressure in the tanks BUT the fumes coming out of the filler tube were very noticeably hot. I did not think to shoot the tank or the tank inlet with my IR thermometer.

So is this the dreaded vaporlock or could it be somethign else? Carb? Remember last week I had backfiring through the carb and went through it. Also replaced both the inline and in carb filters although nothing was found in the incarb filter when I cut it open.

Another data point is that I have installed a new Paterson distributor and have the timing set at 12 degrees. Is there any possibility that the ignition module or coil could cause this symptom.

Tomorrow, we're going to pull the gas line off the mechanical pump and put it in a gas can to verify the electric pump is actually pumping. Then we are going to clamp off the two fuel tank lines to make sure the switch is actually switching. We may pull the solenoid and visually check to ensure it is opening fully.

I've just ordered a new carb from Dick Paterson but don't expect it until nearly time to leave for Branson. I really need to get this fixed. The wife will not deal well with vapor lock.

I'm considering and am prepared to install the intank pumps if that is what it will take.

Thoughts, ideas, wild guesses welcome.


Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
 
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