99 Larson 186 SEI Ski-n-Fish Re-Deck Project

[QuickPuppy]

On to the engine issues. The ‘99 Johnson 115 appeared to be running on two cylinders when I bought the boat. Today I was able to confirm that I have spark on all four plugs which are new and gapped correctly. I replaced the fuel lines on the outside of the boat/engine and mixed up a gallon can of fresh 50:1 premix with some Seafoam in it. I put the fuel line directly into the gallon can, pumped up the bulb, put the muffs on, turned it over and it fired right up for about three seconds. I was not able to keep it running for longer than that. Crank... sputters for a bit, then quits. It does still sound to me like it’s running on less than three cylinders. I’m guessing that the carbs need to be gone though and at least cleaned up if not rebuilt. The pic is what I pulled out of the tank last year.
I’ve rebuilt plenty of Jetski carbs over the years, I assume these would be similar? Any tips to help me get it running are appreciated.

 

[chevymaher]

Flush that gas out of there. Put some lucas injector cleaner in it. Spray the carb out with brake cleaner. That may do it but in reality the carb needs to be taken apart and soaked in laquer thinner and kerosine mix. to dissolve the varnish in the small passages. Then just put a rebuild kit in it. Kit should come with instructions. Look on You Tube someone will have a video showing how to do it.

 

[Mechanicalmike08]

I like your floor panels, mine doesn't have anything down there and it looks like a nice place for driver cup holder and a nice little side storage. How were yours attached? Do you like or hate them.

 

[QuickPuppy]

Mike...
I can’t say if I like the panels or not because I haven’t been able to actually use the boat yet. They are attached to the floor with corner brackets and stainless screws. The drivers side has the radio, cup holder, 12v outlet and a small storage bin as well as the long storage area along the side. The port side has a rod holder and cup holder.

 

[QuickPuppy]

Thanks Chevy,

Anyone have any insight on oem vs aftermarket carb kits?

 

[chevymaher]

Thanks Chevy,

Anyone have any insight on oem vs aftermarket carb kits?

E Bay them there are Mercruiser kits with floats at good prices. Alot of marinas sell stuff there.

 

[QuickPuppy]

Rebuilt all four carbs and it appeared that they had all been recently done. All were pristine inside. I did however find cracks in the float bowls on all of them. That could certainly cause my engine issues. I’m waiting on replacements now.

In the meantime, I replaced the water pump. I am putting the lower unit back on today and will probably check the prop seal and change the drive oil.

 

[QuickPuppy]

Got the new bowls today and installed them. Put the carbs back on the motor and primed the system. The top port side carb started dumping fuel... stuck float. Took it off and cleaned it out again. Reinstalled and primed... held pressure. Took a bit to get it started but it finally did. It was still running on two cylinders. Pulled plug wires on the top two and motor stalled. Pulled the bottom two and no change so double checked that I had spark everywhere and pulled and cleaned out the bottom two carbs again. Squeezed the primer bulb while they were off to try to flush the lines some more. Didn’t really find any issues with the carbs so put them back on. Primed and the bottom SB side now dumped fuel. You have got to be kidding me.
Pulled it again and cleaned it out. Reinstalled... primed... all four held pressure. Started and lo and behold... engine idles normally! Finally.
Tried to slowly ramp up the rpms and could not get it to stay smooth. Looking into carb syncing now.

 

[QuickPuppy]

Anyone happen to know where the port side balance tube hose connects to? I believe this was disconnected when I bought the boat. I thought it was a drain tube of some type. The one from the SB side connects under the front port/middle of the engine under the fuel pump. I can’t find anywhere similar to connect the other one.

 

[QuickPuppy]

That balance tube actually went into the air box.

The engine issues did seem to all be carb bowl related. (Cracked bowls and a gasket that would not seal the bowl to the base.) I read somewhere on here that an outboard without a load on it will tend to try to free run on you. That's what it was doing in my water barrel, so I backed the boat in our pond and it moves under its own power without reving on its own. Even got up on plane a couple times.

Unfortunately I forgot the battery was only connected by the cables, no battery box. Full throttle sent the 60 lbs of battery flying back into the bilge on top of the recently installed bilge pump and float switch. Ahh, more work, just what I wanted. :facepalm: Nothing some super glue and JB Weld won't fix.

Onto the bird's nest of electrical issues the prior owner left me with... Lots of dangling, disconnected, and unlabeled wires everywhere.

I got a bunch of batteries and heavy duty cables (1/0 and 2/0) from an old UPS system we retired at work. Installed two battery boxes and new cables with a battery switch.


The bilge pump, aerator pump, trolling motor panel, voltmeter, horn, courtesy lights, nav and anchor lights, all did not work. Now everything does except for the horn, which appears to be both a bad switch and horn itself. One side of the front panel voltmeter also appears to be a bad battery selector switch. Replacements ordered.

Tonight I will attempt to get all of the wiring dressed up.

 

[iantuffs]

Finally had a chance to work on it again today. Figured out the kick panels... 3 screws took me a half hour to find. Should make it easier to get the rotted deck out a bit further forward.

View attachment 266290



Also got the rear bench vertical support boards out. I think I can remove the decking under the seat now and slide new plywood in place. (The whole bench floats about an inch above the deck as it is part of the cap.)


Also removed, drained and cleaned out the fuel tank. There was only about three gallons in it but it didn't look so good. Lots of oily scum under the tank in the bilge. The hose barb on the pickup tube snapped in half when I tried to get the hose off. Also will need a new gasket for the fuel gauge. It looked half gone. View attachment 266292
View attachment 266294
View attachment 266295
View attachment 266304
View attachment 266305

where did you purchase you Fuel Sending Unit from? I need to replace mine on my 1999 Larson SEI 186. Thanks