Bringing an old Johnson back to life after sitting 10+ years

fmjnax

Chief Petty Officer
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Jul 21, 2011
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457
A couple of years ago I picked an old bass boat out of a farmers field as a project. Their nephew had parked it in 2009 and it hadn't been touched since. $100 for the titles and I got started.

Engine is a 1987 V4 90hp (J90TLCUR). Pistons were shot. Instead of dealing with that, I just bought a remanufactured powerhead. New plugs and wires. Took off the lower unit and checked it out (nothing but oil drained), resealed it, new water pump. Stripped down the carbs and rebuilt them. Replaced electrical/wiring as needed. VRO delete. Completely stripped it down and rebuilt it back up.

Finally got around to bolting everything back up and giving it a test. Have spark, have fuel, but won't fire up. I noticed fuel pouring out the front air silencer cover. Took off that cover and turned the key. Fuel appears to be pouring out the large hole at the top of the housing in between the butterflies and also from the two small brass tubes in the bottom of each throat. Happening on both top and bottom carbs. Doesn't matter if I have the prime solenoid on or off or the engine choked or not.

I had rebuilt the carbs a few months ago and had them sitting on a shelf in my workshop. Before bolting them on, I blew through the fuel lines and confirmed that it allowed air upright but wouldn't when upside down. Still, I suppose it's possible I need to re-clean the carbs since they have been sitting.

It has been well over 10 years since I last had an outboard so I've very rusty. What could be the cause of the fuel spillage and also not firing up? Anything additional I need to look over?
 

racerone

Supreme Mariner
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Dec 28, 2013
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38,452
The primer solenoid has nothing to do with it.-----Clean carburetors and check float and float valve.
 

fmjnax

Chief Petty Officer
Joined
Jul 21, 2011
Messages
457
Well, the carbs weren't directly the problem. I took them both off and completely disassembled, cleaned, and rebuilt with another new kit. Adjusted the floats correctly and confirmed float needle operation. It's not pouring fuel out of the "breather" hole anymore.

Unfortunately, I still have no start. It will smoke out of the exhaust and occasionally backfire, but won't fire up. I did notice that the starter bendix isn't disengaging so I'm going to take the starter off and either rebuild or replace it. Also thinking maybe the flywheel wasn't torqued down and maybe the key sheared so I'll be pulling that to take a look. Battery is also on the charger, though it should have had plenty of juice in it and is brand new.

Carbs do seem to be pulsing/sucking when I put my hand over them. I'll pull the plugs and check them again and will do a compression check. This is a brand new remanufactured powerhead from a reputable source so everything SHOULD be fine with that, though.

Any other thoughts?
 
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fmjnax

Chief Petty Officer
Joined
Jul 21, 2011
Messages
457
Um, yep, I knew the woodruff key was sheared before I even took the flywheel off. I was able to break the nut with my breaker bar and holding the flywheel with my other hand. Definitely NOT torqued down. Pulled the flywheel and confirmed. Looks like I'll be cleaning up the shaft and replacing the key. Hopefully that does the trick.
 

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fmjnax

Chief Petty Officer
Joined
Jul 21, 2011
Messages
457
That did the trick. Put in the new key and torqued down the flywheel nut to spec. Primed the fuel system and she fired right up without any trouble. Now on to the next trouble.

Since I am on muffs, I only ran it until the heads were starting to get hot and only idled, but I wasn't getting anything at all from the tell-tale. Confirmed the drive shaft was working as it should with the shifter. I put on a new water pump a couple weeks ago. The powerhead was reassembled with an entirely new thermostat assembly (stats, gaskets, cover, hoses). I cleared the pisser hose so there's no obstruction (but will check again). Doing some research now, but open to suggestions.

*EDIT* Is it possible that I somehow didn't line up my pickup tube when installing the Lower Unit? The pee hose is 100% clear. When I blow into the end, I can hear air circulating and I can feel a little pressure difference on each of the thermostat-to-head hoses so I'm pretty sure I have an open path without any blockage. It's too hot to drop the LU again today, but I think that is my next course of action. I'll split it again and run a flow test from the pickup tube in the midsection to make sure water flows through the powerhead and then I'll do a flow test on the LU itself by spinning the shaft while on the muffs. If both of those pass, it seems like it has to be an error during install; not getting my tubes lined up.
 
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fmjnax

Chief Petty Officer
Joined
Jul 21, 2011
Messages
457
Case closed. I didn't have my tubes lined up. When I split them again, the impeller pumped water on the muffs while rotating the drive shaft and water flowed through the powerhead from the pickup tube. Put the two back together and paid extra attention to the alignment. She pee's know and runs very well. Thanks fmjnax for figuring it out!
 
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