75 merc carb questions

[kingfisherman]

hello everyone. can anyone give me some literature or advice or maybe even a website on how to properly adjust the carbs on my 1975 85 hp mercury. i dont know much about carbs the more detailed the better. Does anyone have anything that shows what each screw, hole, part does? Anything will be greatly appreciated. Thanks

 

[JB]

Re: 75 merc carb questions

You really need a factory Service Manual, KF.

A lot of folks complain about the price, but it is trivial compared to the cost and aggravation of not having one.

 

[Laddies]

Re: 75 merc carb questions

JB, is exactly right if you don't even understand the components you really need a OEM manual. Here's a chart naming the parts

 

[Chris1956]

Re: 75 merc carb questions

Laddies, Doesn't the '75 Merc 85HP have a sidebowl carb?

Kingfisher, either carb has a single screw adjustment for idle air/fuel mixture. Turning the screw CW leans out the mixture. Turning the screw CCW richens the mixture. The service manual will guide you to start at a certain setting (usually 1-1/2 turns out from lightly seated) and ajust until the mixture is about halfway between too lean and too rich.

For an amateur, this is difficult to do. Why do you want to adjust them?

 

[Laddies]

Re: 75 merc carb questions

YUP, I blew that one, it was for a 1985 7.5HP. Sorry I changed it.