Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Motor won't stay running without pushing the choke

Posted by Nightfishin on 11/11/11 - 8:00 AM
#1

Hey guys. I have a 1994 Johnson 48 spl. The motor was running fine 2 months ago but went to crank it last week and it would not keep running without pumping the choke at the key switch. The motor came on the boat and the owner said it had sat for 5 years. Anyway, I figured it was time to rebuild the carbs anyway so I did that. They were full of garbage. Put em back on yesterday and the top one is leaking a little so I have to pull it back off and see what is going on. At issue is that it still will not keep running without pushing the choke. When I go back to the motor and idle it up it will rev if I do it slowly but it I give it too much gas too quick it will die. When the motor stops I hear a breif sucking sound. I also noticed that after it dies the bulb is not super soft but it isn't tight either. Any ideas where to start? Could it just be the fuel line with a faulty bulb? Thanks in advance.

Posted by JohnnyCW on 11/11/11 - 10:55 AM
#2

Will it run better if you keep gently squeezing the bulb?

I don't know anything about your particular engine but years ago I experiencesimilarar behavior with an old Merc. Turned out mine required a fuel pump rebuild. The check valves were no longer keeping a proper seal.

Posted by Swamp on 11/11/11 - 2:46 PM
#3

It's a fuel thing most likely. I had a similar problem with my 93 60 hp. The needle valves in the carbs were gummed shut. A rebuild and all was solved.

The reason the motor works only when operating the electric primer (choke) is this is dumping fuel into the engine through an alternate path. The carbs might still be messed up. It doesn't take much. Your fuel pump could be messed up. You said there was a lot of junk in the carbs. Take apart the fuel pump and clean out the filter. There is a screen in there. Verify good operation by disconnecting the outlet from the fuel tee and cranking the motor. Use a little glass jar to verify the pump is pumping well. Ensure there are no obstructions in the lines between the tank and the carb.

It is normal for the bulb to go a little soft after starting the motor.

You can find all the diagrams for the motor at:
http://epc.brp.com/

Posted by Nightfishin on 11/13/11 - 12:34 PM
#4

Thanks for the input. I try to do most of this stuff myself because that 80 an hour adds up quick with the mechanics. I am going to pull both carbs and reclean them again this afternoon, and clean the pump as well, but we already verified that it was pumping when we had the carbs off. while cranking it was pumping strong. squeezing the bulb did keep it running longer than not squeezing it.

Posted by Nightfishin on 11/13/11 - 2:45 PM
#5

So i pulled the carbs and pump, recleaned, took the fitting at the remote tank off, stuck the hose in a 2 gallon can and adjusted idle up and all is well. Purring like a kitten. Thanks guys!