1965 merc 1000 ; 100 hp inline 6 strange problem

12volts

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Joined
Dec 10, 2002
Messages
5
This problem is very frustrating. My carbs and fuel pumps were over hauled last year. Motor runs great when under way and starts with no problem. Except when I stop and drift for about 30 minutes. Normally one would just turn key and go. This motor will not start unless you squeeze the primer bulb 1-2 times and apply use the starting throttle, why is this.? I replaced the fuel lines with 3/8. I have 18 gallon vertical type fuel tank with the lines above the tank, the carbs on the motor are above tank level. I am using the see thru generic fuel filter (cartridge type) from west marine. alot of times I see air in the fuel filter and it is never full of fuel except when it is initially primed, never full while under way. Is this normal? are my carbs emptying back into the tank? I replaced the bulb with an oem merc and still the same problem. the bulb gets rock hard now which it didnt used to. if air is getting in, where is it comming from? I have no fuel leaks. I dont have an anti siphon valve. would this help? my tank vent is also clear. Can anyone shed any light on this?<br /><br />russ
 

mellowyellow

Vice Admiral
Joined
Jun 8, 2002
Messages
5,327
Re: 1965 merc 1000 ; 100 hp inline 6 strange problem

check valves in fuel pump changed?<br />good luck,<br />M.Y.
 

12volts

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Joined
Dec 10, 2002
Messages
5
Re: 1965 merc 1000 ; 100 hp inline 6 strange problem

I'm not sure I will have to find that out. I take it if the "check" valves are bad they will allow fuel to leak back from the motor?
 

mellowyellow

Vice Admiral
Joined
Jun 8, 2002
Messages
5,327
Re: 1965 merc 1000 ; 100 hp inline 6 strange problem

yep... check the o-rings on quick connect too.<br />good luck,<br />M.Y.
 

sshdtree

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Joined
Sep 24, 2008
Messages
3
Re: 1965 merc 1000 ; 100 hp inline 6 strange problem

yup o-rings in quick connect not holding prime first one to go is the one at the engine and of corse the one hardest to get to gud luc
 
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