Merc 90 fourstroke stutter and stall

[hard1]

Condensation a possibility, or are you sure it's salt this time? It is that time of year for sure...

[Pete7]

Or is it rain water from the engine being stored tilted ?

Pete

[Hightower]

Well I had a look today and stripped the airbox off to have a peek.

I do admit to having water ingress into the coweling but don't think it's water in the airbox as it's slightly oily but dry looking.

Instead I had a look at the throttle plates inside the carbs and found that when operating the throttle lever one of the plates lags behind the others slightly, so I uncoupled the linkage that connects the 4 Carbs. After opening and closing all of the Carbs independantly I found that the top two snapped shut under spring pressure but the one that lagged behind was binding slightly and would not close fully under it's own steam, also found the lead carb doing the same.

I think it could be coincidence about the water and this problem. I'll book an appointment with the guy that looked at it last time.

Andy

[Hightower]

Not rainwater Pete, it's fully covered. Thanks.

Andy

[The Edges]

Originally Posted by Hightower

Yesterday when having just started my voyage, the outboard was stuttering almost like it was missing when I throttled up (only when accelarating), at low revs. Seemed to clear at 2000 rpm and lasted for about 20 mins. When doing some low speed (tickover) manuvering in the harbour every so often the outboard would stall. And finally everytime I tried to plant the trottle from tickover to full throttle the engine coughed and splutterd and died.

What's up Doc?

Same happened to me this weekend (mariner 90 4st) only happened when tootling back through Chichester at 8ish kts. put it down to low fuel as the pointy end was sticking up and assumed the feed for the fuel line to be somewhere in the middle of tank. I sent my boys to the bow which levelled things off and no splutter

Hope this helps

Andrew