Help with Johnson 48hp

[tsubaki]

When y'all swapped tanks, did you change to a different hose and bubble too?

[Curapa]

Originally Posted by tsubaki

When y'all swapped tanks, did you change to a different hose and bubble too?

Hose and bubble stayed the same. Brand new only been used about 5 trips.

[Destroyer]

Like I said, you've just about fixed or replaced the entire fuel system.. that's why I went electrical.. and if you think about it... when you're on the muffs at home you're not really heating the coils up ... not stressing them the way you do when you're at WOT. I've seen many a coil that went south as soon as it got really hot.. and then seemed fine again when it cooled down.. Anyways, it's still my best guess...

[tsubaki]

We have a similar situation going on with a Mariner and have narrowed it down to the new fuel fitting on the tank or the new bubble. Fuel tank has been drained, cleaned, inspected, all the way up to the new outlet fitting. Vent too.
When we swap to a remote tank and different hose/bubble, the problem goes away.

On the 48 horse I'd be next thinking like Destroyer, look at changing the coils.

[phatdaddy]

probably a long shot, when it starts runing bad, does taking the cowling off affect it. had a old 7.5 honda that dirt daubers built a nest in the cowling vents and it was starving for air. didn't act up on the hose because i usually had the cowling off

[Curapa]

We are going to get a fuel pump rebuild kit from Burns tomorrow. That is the last part besides the fuel line and primer bulb that I can think of to replace or repair.

If no luck we will look at the electrical side.

Cowling on or off makes no difference.

[Curapa]

Just an update...

We disassembled the fuel pump and it was clean as can be. The diaphragm looked great so we put it back together. My buddy dropped the boat back at the shop today. We will see.