My Merc outboard has problem

[linweir]

Recently my 50 HP Merc has a problem.

I can start it easily. Under low speed such as trolling speed, it ran OK. However, under faster speed, it sputtered, then slowly stopped.

Seems motor couldn't provide fuel under fairly high speed.

I changed fuel line with bulb, fuel filter inside, plus filled some new gas in, but issue still there.

 

I am not sure it's related to fuel or electronics, or..? Any suggestion.

 

The motor is year.2008 4 stroke EFI.

[DRIFTER_016]

Could be an electrical issue or it could be an issue with the fuel pump.

Only way to tell is to bring it in for service.

Need to see fuel pressures as well as put it on the scanner to see what's happening in the engine.

[wdodgetruck]

Take the vst tank apart and clean the filter on the high speed fuel pump . Also try running the motor in the dark to check for any

electrical problems . I found a bad plug wire this way .

Edited October 25, 2017 by wdodgetruck

[Headhunter]

Is it the original coil? Might be the culprit?

HH

[Old Ironmaker]

Do a compression test. Last year we installed a rebuilt crate OB on a guys boat. It ran but like crap all year. Sputtered and spit at 3000 RPM, started, trolled just fine. Finally found low compression on 2 of 4 cylinders.

[LeXXington]

Had my 2006 do the same. Ran fine at lower speed put the throttle down runs for a few min then sputters and sometimes dies.

Throttle back no issue.. Tried the same you did bulb, gas, filter,etc

 

Was electrical issue drawing more that the battery could output.

 

Replaced battery with bigger battery problem solved.

[linweir]

Txs for all tips

Tried to use a deep cycle battery to turn ignition on, then ran. Problem still there.

Sent it to marine for service. Hope it's not big deal.

 

Will keep it posted.