3 hp jw 14 won't start

[Yastrimsk]

Hello. I have a 3 hp jw 14 that will not start. I haven't really tried to troubleshoot it too much. I thought I'd ask you guys first before I proceed, because I'm baffled. Last year I put a carb kit in and it ran great ( in the barrel ) when I attached the motor to the boat, no go. Really ??? I mean it would start right up and idle very low, and it would throttle up nice too....... in the barrel. But when I went to use it, I couldn't even start it !! I've got great spark to both plugs. They're getting wet ( but not soaked ) in fuel. Compression was always very light ( easy to pull over ) but ran nice. I'm pretty sure I don't have the plugs crossed. I've monkeyed with needles and tried different settings, but no go. I can start it, but only for a split second. I seems too me, that it's deprived of fuel ? My Pistons have some carbon build up, and my compression tests are = , but only 50lbs. That seems a little low to me too, are my rings stuck ? What confuses me is its always pulled over easy....... yet started right up. Fuel was fresh and clean. Any suggestions ? Thanks so much in advance.

 

[oldboat1]

Great spark is 1/4" to 3/8" or so measured with an adjustable tester. Tank vent and fuel shut off have to be open, of course (presumably, like in the barrel). You might start over with the needles when on the boat. Start with about 1 turn open for the low speed, maybe slightly more, and about 3/4 open for the h.s. I would use a 16:1 mix.

 

[lindy46]

Plugged filter? Filter is in the tank above the petcock.

 

[Yastrimsk]

I'm assuming I'm good there, because I have good flow to carb. I think I will eventually replace fuel and will check that just to be safe.

 

[lindy46]

If you're sure fuel flow is strong enough to run the motor at WOT, then check the float. Did you put in a new float and adjust it properly? If the needle is closing too soon or stuck shut, that would cause a fuel delivery problem. The rubber-tipped needles can stick in the orifice if you don't install the little spring clip that comes in the kit.

 

[Yastrimsk]

Thanks for the replies. Im going to start over, starting with fresh gas. I will also take another peak at the carb. I did replace the cork float, but didn't use the rubber needle, but I will take a close look at the float/needle.

 

[Bonaventure]

I would make sure the tank is clean, the filter as well then put new gas in. I think it may be that your high speed needle is set too rich. I believe t is better to adjust this setting on the boat under load.

 

[F_R]

50 PSI is too low on compression, assuming you have a compatible gauge. That would explain the hard starting in the water too. Too much back pressure on the exhaust for the powerhead to overcome. Confirm by starting it up out of the water (remove the lower unit first if you value the water pump). If it runs out of the water but not in the water, well there ya go--

 

[Bonaventure]

I think my post was a bit hasty. I should have read the original post again. F R is right, this is a compression problem and some serious motor overhaul will probably be needed. I would guess that disassembly,boring out both cylinders for oversized rings, cylinder honing and then reassembly is likely to be the solution. It may be feasible to find an engine like yours that does not need this work and to use this one for a parts engine.

 

[oldboat1]

mmmm...."got great spark..." Measure it with an adjustable tester. Put in new coils when you did the carb work?

50 psi ain't great, but then only 60 or 65 would be considered OK on the 3. Try another tester, as suggested. Test with both plugs out, and pull it over until the needle stops rising, probably 5 or 6 times.