Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Engine Idle Question??

Posted by Troy on 08/30/08 - 4:29 PM
#1

My Johnson 120 V4 seems to want to die more often than I think it should. Even when it is warm it will somtimes stop running when put in neutral. Other times it will idle just fine. It also will occasionally stop running when in forward gear at very low rpm. That one doesn't bother me as much. I have been adding Seafoam. What's the best way to correct these issues?

Posted by RevengeFamily on 08/30/08 - 5:46 PM
#2

Always check the simple things first. I have to ask... is your fuel fresh? When it does idle, is it smooth? rough? When it does stall, does it give any warning or does it just die?

Regards, Norm

Posted by joninnj on 08/30/08 - 7:40 PM
#3

Troy,

I agree with Norm, always go for the basic stuff first, tanks, filters, fuel line, primer bulb, vent on the tank... BTW, what RPM does it stall at in forward, it you are talking 600 RPM or less, then raise idle to 650 - 700 in forward.

If no luck, then go to the more invasive stuff, drain carbs if you can, there may be brass nuts at the lower section of the carbs which can be opened allow them to drain (have paper towels on hand). Could be junk or water in there which seafoam will not flush out.

Then go to the fuel pump, if your primer bulb is soft while running (and the line is new) fuel pump may be the culprit... The diaphrams stretch and can tear if they are old. This is a part that people seem to forget and it is easy to replace... It can cause headaches if ignored...

If this fails then bring it in to the shop...May need new jets and deep cleaning on the carbs. Also think about a compression test although it does not sound like deep internal problem, good info know.

Good luck...

Edited by joninnj on 08/31/08 - 5:05 AM

Posted by Barryg on 08/30/08 - 7:40 PM
#4

Troy, have you checked or tried to adjust the idle ? BG

Edited by Barryg on 08/30/08 - 7:41 PM

Posted by Troy on 08/31/08 - 5:09 AM
#5

The fuel is fresh. When I bought the boat, the fuel had been in for a while, so i ran the tank through and put in fresh. I've refilled a couple of times since. Seems to run smooth. It doesn't give any warning when it stalls, and I would say it probably is below 600. I haven't tried idle adjustment. I thought I would check with you guys before trying to remedy anything. I was concerned that upping the idle RPMs would cause it to jerk into gear. Then again, I think I have plenty of wiggle room on that one. I'll start to tinker with her using your collective suggestions and post back to let you know how it goes. Thanks for all of the ideas and advice!

Edited by Troy on 08/31/08 - 5:15 AM

Posted by Troy on 09/13/08 - 3:13 PM
#6

Problem is solved. I tinkered a little including a little adjustment with the idle scew and it seems to be good. My rpm guage doesn't read well at lower rpm's, so its anyones guess as to what the idle is actually set at now. Nontheless, it's running great!