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1996 Johnson 15hp Poor Warm Starting and performance

tomjoh

New member
The story begins:

I had a 91 merc 15 hp that was perfect. but it was stolen from my 14 ft alumacraft. It could push the boat up to 24 mph (gps) and started every time.

I recently purchased a 96 Johnson 15 hp that was well cared for but stored for the last year and a half. By all appearances it was very well maintained.

The biggest problem is that the boat starts very difficult after being warmed up. It starts immediately when cold.

Once warm, if shut down it needs to be immediately choked and pulled twice to get a cough and then 3 pulls later it starts without the choke. I've tinkered with the fuel idle mix and the performance with the cups is great. However, in the water it is now worse.

The bit I have read says this could be related to the float valves, can anyone confirm?

Secondly, the merc would push up to 24 mph and this one tops out at 19. It seems like it should have a lot more left. Any suggestions on this? it runs very smooth at WOT.

Thank you for the advice!
 
Re: 96 Johnson 15 Poor Warm Starting and performance

try pumping the fuel bulb before you try to crank it warn, let us know what happens.
 
Re: 96 Johnson 15 Poor Warm Starting and performance

Cranking the fuel bulb doesn't do anything.

I'm soaking the carb as I write.

The strange thing to this is how consistent it is.

I am bringing the compression gauge to the lake tomorrow.

Why would it be lean (requiring a choke to start) when warm?
 
Re: 96 Johnson 15 Poor Warm Starting and performance

I have had 2 of those motors and both operated the same way, hell to start the 1st time but ok afterwards.
 
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