1996 Johnson 150 won't start

[Poopdeck]

So my preacher gave me a boat because I needed an engine for a different boat. The 1996 60* Johnson 150 looks great but was completely stopped up with varnish where the boat had sit for more than a few years. I mean this stuff looked like tar. Anyway, I took everything apart and cleaned it all. Carbs, reed valves, manifolds, fuel lines, everything. Put it all back together and it ran great but the primer solenoid didn't work so I rebuilt it and now it works too. Now to the problem, I have a large fuel tank under the deck, a fuel/water separator then a clear fuel filter prior to the outboard. Once it goes into the cowling the fuel line goes into the VRO. The VRO is unhooked from the oil line so that is not in play here. I have gas in all 6 carb bowls but can not get the engine to run. It won't even fire. It will run fine spraying fuel into the carb throats but not on its own. The fuel line is tight, so tight it leaks from the fuel lines if I want it too. What am I missing? Why won't this thing run anymore? I had it running on a portable tank while cleaning it and now it's on the big tank but it ran on the big tank also prior to this. Any help would be awesome.

 

[oldboat1]

Condition of fuel? Draw from the large tank at the intake (use the hand pump). Water settles lower than fuel. Let the drawn fuel settle in a glass jar and look for separation.

IMO, the water separating filter is enough filtration. It can be overwhelmed, however. Check it to see if it's more water than fuel.

I've seen an awful lot of project motors, but don't think I've run into one with as much varnish(?) as yours. I think I would continue working on it with the portable tank for a while until the mystery of the big tank is solved.

 

[Poopdeck]

Yeah it was bad. There was even tar on the piston side of the reeds. All the small holes in the manifolds were completely plugged. Everything was covered in sticky tar-like varnish. It was everywhere.

The boat tank was drained and cleaned by me. It had water in it and lots of pieces of the old float and sending unit. I shop-vaced the entire thing as best I could with a homemade contraption to get as much as possible through the sending unit hole.

I'll continue with the portable but the fuel coming into the carbs from the boat is clean.

Thanks for the reply.

 

[dingbat]

Have you checked fuel pressure using the big tank?

If the fuel pump is OE it’s long past it’s prime. The extra head pressure required by of the big tank might be putting it over the top.

 

[jakedaawg]

Did you clean the throttle bodies? Small orifices in there for idle and mid range

 

[Poopdeck]

I cleaned everything. By throttle bodies I assume you mean the pieces between the reeds and carbs. I called them manifolds but yes I cleaned them. They were completely stopped up.

The fuel pump I assume is OE. It was working though. I can pump the line tight and it never looses pressure even after cranking the engine over unless I take something apart in the fuel circuit. To me that suggests the carb floats are all sealing and the bowls are full. Opening the bowl drains confirms that.