72' Merc 65 hp, flooding issues

jacobmorin

Seaman
Joined
Dec 27, 2006
Messages
51
The old 72' 65 hp Merc with Merc controls has been starting fine all summer until recently. Usually when I get in the boat I pump the primer ball about 3 or 4 times until it becomes real hard, hit the choke twice, hold the choke button while turning the key and the motor starts right up. Now when I prime the primer ball it isn't staying too hard and I can actually see the gas being pumped into the carbs? Of course the motor has been flooding and I have to sit with the motor trimed up until the gas drips out, than it starts right up? Does anyone know what might be wrong? Also, is this a quick fix?
 

jacobmorin

Seaman
Joined
Dec 27, 2006
Messages
51
Re: 72' Merc 65 hp, flooding issues

Also, in some of the forums I see mention to bad stators and primer balls, does this sound like any of these fixes.
 

erniex

Petty Officer 3rd Class
Joined
May 26, 2004
Messages
93
Re: 72' Merc 65 hp, flooding issues

If your primer bulb won't stay hard and your carbs are flooding when you pump the bulb, your float bowl needle(s) are probably stuck open. As it was working allright, may have gotten some crud in the gas stuck between the needle and seat valve in the carb. float bowl. May need to open them up, clean and reset the floats.

EE
 

jacobmorin

Seaman
Joined
Dec 27, 2006
Messages
51
Re: 72' Merc 65 hp, flooding issues

Thanks! I thought it might have had something to do with the floats.
I am not a mechanic, however I do have the SELOC repair manual. Do you think this is something a first timer can do, or do you think it should be professionally done? Also, if a marine mechanic were to do this, do you know how much it might cost?
 

erniex

Petty Officer 3rd Class
Joined
May 26, 2004
Messages
93
Re: 72' Merc 65 hp, flooding issues

Those carbs are pretty basic. If you have the basic tools and follow the manual it is not a difficult job at all. More work to get them off than to rebuild. If your going to remove and clean, I'd go ahead and get the basic rebuild kits (Needle valves and seat, gaskets), disassemble, clean, reset float levels and reassemble per the manual. Make sure the floats are not saturated with gas (older type can absorb and will not float properly)...they are replaceable if they are. I would expect a minimum of a couple hours labor charge from a shop plus parts. Rebuild kits are fairly cheap and there is plenty of help here if you get stuck - can also search forums for carb rebuild - lots of info. Well worth taking this on yourself!
 
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