1969 merc 350 35hp fuel and fuel pump questions

[tsutter]

Hola:<br /><br />I've got a couple of questions about my 1969 Mercury 350 35hp outboard:<br /><br />1. Can someone describe to a layman (me) in layman's terms what "flooding" means? I mean flooding in regards to fuel, not in regards to keeping afloat. Part of the reason I ask is that the carb does not leak while it is running, but leaks a bit when I shut the motor off. Is this normal?<br /><br />2. I put a new fuel pump diaphragm kit in and noticed my kit has 2 circular gaskets, 2 gaskets in the shape of the fuel pump, a diaphragm, and what looks to be another type of gasket and is black in color and in the shape of the fuel pump. However, when I read my seloc manual they describe the kits as being composed of just the 2 circular gaskets, 2 fuel pump gaskets and the diaphragm (basically what was in the fuel pump when I started). What gives? i.e. what is this additional piece in my kit? I put it in anyway and don't think I noticed anything different in the running of the motor.<br /><br />Thanks in advance for all your replies.

 

[Chinewalker]

Re: 1969 merc 350 35hp fuel and fuel pump questions

Hi TSutter,<br /> Flooding is generally referred to as the condition of getting the motor wet with fuel. If the motor is over-choked to the point wher the plugs are wet-fouled, and raw fuel is running through the motor unburned, it's flooded. Some motors are easier to flood than others. If a motor isn't starting and you're seeing fuel bubbles on the water (rainbows!) then you're probably flooded.<br /><br /> Pieces you'd need out of the kit. Two gaskets, one for either side of the diaphram; The diaprham; The two round gaskets which seat under the check valves; and the base gasket, which goes between the pump and the flange on the crankcase...<br /><br />- Scott

 

[tsutter]

Re: 1969 merc 350 35hp fuel and fuel pump questions

Thanks chinewalker:<br /><br />Great. Gotta rip out the rebuild. Appears I put the base gasket in between the 2 other gaskets and on one side of the diaphragm. <br /><br />As far as the flooding being a result of a motor being overchoked, I have to hold the choke down a little at first while starting. Maybe flooding is the result of this?<br /><br />Thanks again and I'll keep y'all posted on any and all developents tied to this topic.

 

[tsutter]

Re: 1969 merc 350 35hp fuel and fuel pump questions

I reset the base gasket on the fuel pump in the correct position. <br /><br />But one other thing I tried that I hadn't before: Instead of pushing the neutral throttle lever all the way up to start (resulting in starting at high rpm's), I lifted the lever to about 1/3 to 1/2 height and turned the key. It fired up right away and all I had to do was choke it for 2 seconds and it purred. Not only that, when I did drop the lever, it idled continuously. No leaking gas during running or after when stopped. <br /><br />So what gives here? Someone please put this monkey in line. Is it possible (probable) that pushing the neutral throttle lever all the way up to start the motor actually flooded the motor instead?<br /><br />Chinewalker, I remember seeing one of two of these engines on your webpage. Are they electric start? If so, what is the procedure you use to start? Any other Merc 350 owners out there?<br /><br />Thanks everyone.

 

[tsutter]

Re: 1969 merc 350 35hp fuel and fuel pump questions

^^

 

[Chinewalker]

Re: 1969 merc 350 35hp fuel and fuel pump questions

Hi Tsutter,<br /> My '66 is an electric start. I've always put it about 1/2-way up on the warm-up lever. On mine it was always a barely touch the key and it starts type motor. It is entirely probable that you were flooding it out by putting it right to the wall. The big Merc twins may not be the most popular motors out there among Mercophiles, but I like 'em... Good power, and lighter than a similar powered OMC Big Twin, and a darn sight better looking...<br /> Enjoy!<br />- Scott