Have 78 Barth, 454 engine, after market headers which was on motor when I got the Barth. In hot weather engine has vapor lock when using fuel out of right side tank only. Any ideas how to stop this problem?

I am certainly not Click or Clack but it sounds like a gas cap problem to me. If you had normal vapor lock it wouldn't matter what tank your using.

quote:

Originally posted by bill h:
My 84 has only one tank, so I can't be too specific here.

Vapor lock can be attacked from two directions, pressure and heat.

Does each tank have its own electric pump? It so, check for both pressure and volume. If not, install an electric pump an near to the tank outlet as possible.

As to the heat, an insulating wrapping around the fuel line, or a shield or barrier between the exhaust and the line may help. Make ther isn't an exhaust leak blowing hot air on a line. Believe it or not, I had a leaky tailpipe blowing hot exhaust on a fuel tank, causing the whole tank to boil audibly. That had to be the ultimate vapor lock! Ram air can be ducted to flow on the area of the fuel line near the exhaust. I Have also threaded a duct over the fuel line, with the line extending through a hole in the side of the duct. The end of the duct extends forward to catch cool ram air.

In general, MH engine compartments get too hot. I have two 4 inch flexible ducts running from under the bumper to each exhaust header to provide cool air, and one to the air cleaner snout.

Isn't it a little early for vapor lock?

Hope this helps

Bill

Bill,

Thank you for your reply. You and Dave Bowers made some interesting points. I may have several problems. You mentioned a boiling fuel tank. The exhaust pipe from headers runs under the left side tank about two inches below tank. Several times, when refueling there has been a pressure build up in this tank causing a wait of maybe thirty seconds for the pressure to clear. I will need to extend exhaust pipe and some sort of heat shield to protect left side tank.

No electric fuel pumps on fuel tanks. Will look into adding those to tanks and the air ducts. Already installed some heat shields between headers and frame where fuel lines are located and was planning on wrapping lines that are still exposed to exhaust heat.

Will agree engines compartments get way too hot. No vapor lock so far only notice in warmer seasons, but want to fix before then.

Again Thank you

Kenny

quote:

Originally posted by davebowers:
I am certainly not Click or Clack but it sounds like a gas cap problem to me. If you had normal vapor lock it wouldn't matter what tank your using....

Dave,
Thank You for your reply. This isn't a normal vapor lock as you suggest. Left side tank has a pressure build up from exhaust pipe running too close to tank. Your and Bills reply brought this to my attention. I again Thank You

Kenny