MH Hawker
Vice Admiral
- Joined
- Jul 13, 2011
- Messages
- 5,516
I have a Canadian made 1996 mariner 9.9 Ser # 0G119661 on a 20 foot pontoon boat remote controlled. I seam to be having a fuel fluctuation issue. The motor has been ran a good bit over the summer and over the last few weeks I have noticed a change in performance it wont hold a constant rpm. I normally run it at 4000 and it will slowly drop off to 3600 to 3800 and if I add a bit more throttle it jumps to 4200 t0 4400 and then starts dropping off again unless i go wot, and even that has dropped off from 5400 to 5000,. And today while I was out it didn't want to idle, normal idle is 900 to 1000 in gear and today it dropped off to 700 or died. The only change was I did have to get 2 new fuel tanks due to the old ones being stolen so right now I am suspecting the fuel fittings on the fuel line, their less than 2 years old, got a new line last year. I use only pure gas from the marina. I ran into this same sort of a problem with a Nissan last year and it turned out to be a bad O ring in a fitting. My plan is tomorrow is to get 2 new fittings and give that a try.