'99 Johnson 115 V4 Stalls at idle while warm, fine when cold.

[Captain Jeff]

Hello,

My 1999 Johnson 115 60 degree V4 idles great in neutral and in gear when it is relatively cool BUT After I have been running it for a while and it has warmed up and go to idle either in gear or neutral it will idle for a bit and stall. If I restart it, it will stall again after 10-30 seconds unless I keep pushing in the key primer solenoid.

This motor has been doing this for the past couple of years. It is well maintained and I have rebuilt all 4 carbs, new VRO, new powerpack and optical sensor and the normal maintenance stuff. Just did a link and sync too.

This is driving me crazy, it is a lot of fun when it is windy out and you are trying to dock with your boat constantly stalling. Also, maybe unrelated but I only do about 4900 RPM at wide open throttle. This is on an 18' V hull center console boat. The throttle plates are fully open. This is with the stock 14 1/2 X 19 prop. Thank you for your help.

 

[tashasdaddy]

Re: '99 Johnson 115 V4 Stalls at idle while warm, fine when cold.

well i suggest you check compression and spark first, you are either not running of all cylinders, or definately have the wrong prop. you should be turning 5500-6000 rpms, preferable to the high side. it is also very possible, you have one or more clogged low speed jets. what are your in gear, in the water, idle rpms?

 

[Captain Jeff]

Re: '99 Johnson 115 V4 Stalls at idle while warm, fine when cold.

Thanks for your response. I did not get to check spark or compression but when I have checked it in the past, both have been good and I had the same problem at those times too.

When the motor was cold my RPMs at idle were:
750-800 in gear
850 in neutral

Once the motor was warmed up:
850-925 in gear
1025 in neutral

I did better on WOT this time too at just over 5000 with only two people in the boat vs 4 the other day. Last night the motor actually stalled once while cold at idle in gear. Thank you again for your help.

 

[tashasdaddy]

Re: '99 Johnson 115 V4 Stalls at idle while warm, fine when cold.

i think you either have carb problems, or linc n sinc problems. you idle should be 600-750 in gear in the water, the lower the better, the faster the idle the more wear of the clutch dog when shifting. you need to do compression and spark. that was then we need now.