Sunday, September 1, 2019

Figuring out MPG/ KPL and all that stuff....

With a rig as big as our Allegro, the issue of fuel economy comes up on almost every trip. With gas over $3US per gallon any increase in efficiency is welcome.

Okay, I spent some time and money rebuilding the carb and on the trip up to the 1000 Islands the economy seemed to be pretty good. Nearly 10 mpg is nothing to sneeze at. On the trip back the mpg decidedly took a steep dip down back into the old 6.5 mpg range.

Well.... there may be a reason for that. I just moved the RV around in the driveway and spotted quite the trail along the pavement. So much so that I tracked it down and felt that it might even be a safety hazard. I did find a leak right after the Carter fuel pump and the cracked hose was spraying gas all over the LP tank!!!! No kidding! I took a picture of it.

 The yellow oval shows the hose and on the left is the actual spray while the pump is working!!!
The Carter fuel pump on order to replace the original one above. Brackets and all.


Since the pump is likely original (33 years young) and the associated connectors, I decided to just order and replace the pump and hoses.

Here are pics of the parts on order. A YouTube vid will be available for the install.
View the later video of the fuel pump, filter and line replacement this weekend. Got a decent boost of performance with this work duns!

Replaced Fuel Pump and lines....

UPDATE: After driving the RV and working on getting the ONAN to start remotely again with the cheap carb replacement I had an incident last evening that could have ended in disaster. What I thought was the fuel flow needle valve managed to vibrate loose and come completely out of the carb. This was in reality just a brass bolt plug at the base of the carb (no fuel flow allowed I guess) and when performing my regular start-up for the genset it managed to just come out and land on the genset. This allowed a substantial amount of fuel to spill out onto the genset, all over the genset exhaust on onto the ground. Luckily I smelled the gas and shut the genset down. I felt around where I could see the fuel leaking and realized that bolt had fallen out! I new O ring, copper crush washer and Red Locktite solved this issue.

Be safe out there and always check, test and keep an eye on your RV systems!! You can never be sure when old, original parts will give out. Glad this happened in the driveway and not on the road.

UPDate: I've done a couple of shorter trips in the RV. The last one was about 40 miles and I averaged about 9 MPG on this one. I would say that the conditions have improved over the last trip with the leaky fuel lines. If this is something to look for the tank could have 576 miles per fill up in the future. Not betting on it but it's a goal worth going for!