sudden stall out then rough idle

[tystick]

i have a 1990 merc 4.3L that ran beautiful 1st time out then when returning to dock...it suddenly died. I did get it to run rough in driveway the next day but I could not attend to issue until now. <br />Several months later...i startered up again and it seemed to run fine - no rough idle. Checked fuel filters and were ok. Could it be crap in tank that was disturbed and blocked pick up tube and then settled back down after sitting?<br />thx robert

 

[vicsponjr]

Re: sudden stall out then rough idle

I had a similar problem every time I got to my no wake zone. I had my idle too high, so I was always pulling back on the throttle, and I believe the shift interrupt was engaging, which slows down the engine to assist the drive in shifting. Always smelled like it was running very rich when it happened. My shift cable probably isn't adjusted properly. <br />I'm no expert, but maybe your having the same problem.

 

[Bondo]

Re: sudden stall out then rough idle

Checked fuel filters and were ok.

Changed,.. or Checked,...??? How,.??<br />

Could it be crap in tank that was disturbed and blocked pick up tube and then settled back down after sitting?<br />

Or,.....<br />It could be Crap laying in the Float Bowl....................

 

[vicsponjr]

Re: sudden stall out then rough idle

How about the anti-siphon tube for blockage?

 

[vicsponjr]

Re: sudden stall out then rough idle

How about the anti-siphon tube for blockage?<br />If it ran good at open throttle and had problems at idle I don't think it would be a fuel delivery problem. But if you haven't changed all the filters I would definately do that first. Your fuel may also be contaminated. How long did it sit?

 

[tystick]

Re: sudden stall out then rough idle

Victor,<br />It sat from last season. Started right up - no problem - ran for over an hour - then died when coming into dock. Filters are new but did not check tank itself yet. Is anti-siphon have the flap?<br />thx robert

 

[craze1cars]

Re: sudden stall out then rough idle

Not saying this is it, but it's possible that a little bit of water/condensation is in the tank from off-season storage. That can cause some stumble/die situations that cure themselves after a few fill-ups. I've had this happen a few times.