2000 Johnson 150HP hard to start after sitting

[scboater53]

I have just bought a Wellcraft with a Johnson 150hp on it. The engine only had 136 hours on it. It starts and runs like a champ but when hot and after sitting for a few minutes it is hard to start and when it does start runs very rough like it's flooded. The plugs are new and the comprsssion checks great. Prior posts all point to the fuel pump diaphragm but on this year there isn't a rebuild kit. The fuel pump must be replaced (part cost $375). I would like to know if there are any suggestions on how I can verify that the problem is the fuel pump and not something else before I invest in a new pump.

 

[reeldutch]

Re: 2000 Johnson 150HP hard to start after sitting

did you check for spark when its hard to start?
how do the plugs look like ?

 

[scboater53]

Re: 2000 Johnson 150HP hard to start after sitting

I have not checked the plugs. I am a little "handy" and this acts like the engine has gotten flooded. Once you get it started it smokes and runs rough. Once you leave the dock and give it speed it smoothes out and runs great again. The problem largely comes while trying to trailer it after tying it up to go back the trailer into the water. What would I look for if I start pulling the plugs?

 

[jonesg]

Re: 2000 Johnson 150HP hard to start after sitting

I What would I look for if I start pulling the plugs?

plug condition, they tell a tale.

keep each plug matched to its cylinder and make note of each one in your service manual, got one right?
www.outboardbooks,com
or
evinrude.com

it could be heat soak, test that by keeping the engine idling when you stop, then pump the bulb up firm when you stop it.
If it fires up ok then its heat soak. The fuel gets boiled off in the bowls.
Do you have metal bowls, got carbs ??

 

[Dhadley]

Re: 2000 Johnson 150HP hard to start after sitting

What spark plugs are you using?

(Note - your carb bowls are plastic. All 6V6's have plastic carb bodys)

 

[scboater53]

Re: 2000 Johnson 150HP hard to start after sitting

Thanks for all the help. The bulb is still tight when we have the start problem.

 

[reeldutch]

Re: 2000 Johnson 150HP hard to start after sitting

may be a needle thats not closing all the way.

when you sqeeze the primer bulp can you see fuel leaking from the carbs somewhere?

 

[scboater53]

Re: 2000 Johnson 150HP hard to start after sitting

Thanks for the suggestion. I will check to see if there is a leak.