Outboard Help

[blaze]

Hi all
Outboard in question is
1978 evinrude 70 hp
The only problem to date has been black box failure
Last trip out I noticed, after idling and working a school of fish, the revs wer'nt real responsive to wot, lots of hesitation.
My thoughts at the time was it may of oil the plugs, as it cleared it self and never faultered again that day.
Today the motor seamed to run out of fuel, pumped the primer bulb and it pcked up revs and seemed o/k, then decided that I would return to ramp and on the return trip the revs were going from wot to nil wot to nil, sorta pig rooting all the way back to the ramp (only about 500m). I think it is a fuel problem (thought maybe dirty fuel, but have got fuel from the same place for 20 years with no prior problems), cleaned out the fuel strainer on motor and found only a small amout of shit and no water. may be a air leak as i found a small leak on the inlet hose between the strainer and the carbies. just like some thoughts from other members.
Does any body use those small inline filters in their fuel lines
cheers
blaze

[landy1]

G,day Blaze
Mine had similar problems before the latest fiasco, its an evinrude of similar vintage but a pull start 25hp. the problem turned out to be bad spark from poor points and condenser. dont know if this helps.
cheers
Michael

[blaze]

Hi michael
mine o/b has electronic ignition and the unit has only been replaced about 6 months ago
cheers
blaze

[budgie]

G'day Blaze,
Might help to look at the fuel pickup in the tank, i had a similar problem and it turned out that the pickup gradually became clogged as the tank was shaken up, revs would drop, you could pump the primer and revs would pick up again. Worst part about it was after the tank settled for a while everything seemed OK, then on a big trip and it would start all over again!!!!
Cheers, Budgie

[blaze]

Hi budgie
Tanks are plastic and only about 12 months old, same problem on both tanks. I will pull the pickups out and have a look though, helps to eliminate.
cheers
blaze

[drevil]

Have you checked out outboardrepairs.com? It's a great site with heaps of stuff about problems like this.

The link to the Evinrude section is http://www.outboardrepairs.com/evinrude/

Hope it helps.

[blaze]

Hi drevil
top link going to replace some fuel lines today, just to eliminate sucking air, I will give the old girl a run then
cheers
blaze

[blaze]

Hi all
Thats a good link drevil, o/b is now fine, replaced a fuel line from the external connection to the pump ( may have been sucking air at the pump) and removed 1/4 of a thumb nail of shit outa the strainer in the pump ( must fit a fuel filter) Went for a run out the bay 30 knot eastly winds, bloody rough, not ideal test conditions, after running around for about 1/2, very happy again. Must do winter maintance earlier
cheers
blaze

[littlejim]

blaze,

have a similar evinrude. Had an experience almost identical to yours. In my case the fuel line which is fairly long, got trapped behind something at the back and got a kink in it. At low revs enough fuel got through for normal performance, at high revs the carby bowl kept it going until drained, then it would only run at revs that matched the small amount of fuel coming past the kink. Straightening the fuel line out fixed the problem. Of course it took a while to work out what the problem was.