Air/fuel mixture port supposed to be plugged????

[ahickman]

While dissasembling and cleaning the carb bowls on my 88 Force 125, I noticed that one of the two carbs was missing a plug in the air/fuel mixture needle area. I happend to look down below the carbs and found a shiny piece of aluminum that looks like it popped out of the port. Anyone know if the hole just above the air/fuel port should be sealed off?

 

[pnwboat]

Re: Air/fuel mixture port supposed to be plugged????

I'm pretty sure it's supposed to be sealed. You can verify by looking at the other carburetor.

 

[ahickman]

Re: Air/fuel mixture port supposed to be plugged????

2 questions:

1. Would the missing cap allow too much air in the intake, causing the lower two cylinders to run very lean? Could this have been the cause for my hot temp alarm at higher RPMs?

3. Anyone have a picture or two of their carbs (125 Force, 1988) that show this cap in place?

 

[ahickman]

Re: Air/fuel mixture port supposed to be plugged????

I believe I just found the answer to my question about the missing cap. The are sold in quantities of 4.

http://www.crowleymarine.com/mercury-outboard/parts/1258_80.cfm

 

[jerryjerry05]

Re: Air/fuel mixture port supposed to be plugged????


It would cause a lean condition,not sure about an overheat.
Yes replace it.Seal it in place with Indian Shelac.
It's impervious to gas.
The carb should be clean/dry to apply.
Being from Va.you've probably run in salt water or someone has.
The passages in the exhaust could be blocked and causing an overheat situation.
Some people don't flush as good or as often as they should.

 

[ahickman]

Re: Air/fuel mixture port supposed to be plugged????

Jerry,

Always good to see you chime in. Lots of good postings/suggestions I see from you.

With regard to the overheating, I just took (broke) off the final bolt and opened up the exhaust plate. Only a little spoon full of sand in the bottom corner of the plate. All ports seemed to be open. Just the expected white crusting on all surfaces. About 1/32" thick so it doesn't seem to be worth the scrubbing.

When I removed the thermostat plate, I saw the same crust, but did not see any blockages. Shot water from a hose into it and water flowed out the snout and nostrils. Assumed passages were open. Where else should I look? Please don't say, "remove the head" because I fear those bolts snapping off.