86 OMC Cobra Issues Running Above 4k RPM

dodgeramsst2003

Petty Officer 2nd Class
Joined
Apr 15, 2008
Messages
177
Hi all,

Sorry if this has been covered before, but I didn't find anything in my search. I just bought a new to me 86 Crestliner 22.5 ft Sabre GL. It has the 4.3L OMC Cobra engine/outdrive combination. I've been boating for over 20 years now, but this is my first OMC.

The engine runs great, starts good, idles good, gets up on plane just fine, the problem is when I try and go over 4k rpm, the engine just bogs down. If I pull back on the throttle it picks back up and is fine. It has had the electronic ignition conversion done to it, been maintained regularly etc. I didn't pick up on this problem during the sea trial as it was rough and we couldn't open it up. I've only had it out twice, so haven't had a lot of time to troubleshoot it. Any ideas on where I should start? I feel that it is running a little rich at idle, and I'm not sure if this is across the powerband or not. This wouldn't be the first boat I've owned that ran rich at idle, so I'm not sure if this is happening at the top end or not, never had any issues before.
 

Maclin

Admiral
Joined
May 27, 2007
Messages
6,761
Have you replaced the fuel filter(s) yet? There may be one in the carb inlet.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,110
the problem is when I try and go over 4k rpm, the engine just bogs down.

Ayuh,...... It's runnin' outa gas, a fuel delivery issue,.....

Could be as simple as clogged filter, or the carb needs a rebuild, or the tank ain't givin' up it's load,.....

I've been boating for over 20 years now, but this is my first OMC.

OMC went belly up, 'bout the time you got inta Boatin',.....
Now a days, replacement parts are gettin' harder, 'n harder to find,.....
 
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