Mercarb rebuild and float drop

[dancewithme951]

I'm rebuilding a Mercarb 3304-9565A1 and, per the official Mercruiser service manual, Vol. 7, it mentions TWO diffferent float drops - 32 mm (in specifications at beginning of mercarb section) and 27 mm (later in the reassembly description).That seems to me a huge difference; does it matter which I use or is there a consensus as to the correct one?

 

[Fun Times]

Re: Mercarb rebuild and float drop

Use the 27 mm.

Also you need to know what needle and seat you have for the correct float level.
Read this,
http://www.boatfix.com/merc/bullet/89/89_21.PDF
and this before proceeding,
http://www.boatfix.com/merc/bullet/97/97_08.PDF

 

[dancewithme951]

Re: Mercarb rebuild and float drop

Thanks for the info and links. I have the solid 3 piece needle so I'll set float level at 10mm and drop at 27mm.

 

[nwboater45]

Re: Mercarb rebuild and float drop

There are a couple of real good carb rebuild vids on YouTube from Mikes Carburetor. I rebuilt mine last year and found the videos to be very helpful. He explains the float drops and how to measure them.


https://www.youtube.com/watch?v=JHjjAz367Ng

 

[dancewithme951]

Re: Mercarb rebuild and float drop

Thanks for the link but I had already found them and they were invaluable in my rebuild. I've completed, installed and she's purring like a kitten at idle and roars like a lion wide open!!