25hp Merc Inlet Needle Spring?

[Cordovakid]

I am in the process of rebuilding the carb on my 1980 Merc 25hp, as I have always suspected this carb to be flooding (symptoms include rough low idle, hard start after a few hours, wet plugs, bulb going a bit soft after 20 minutes). The float appears to be in good condition (ie. no punctures, leaks, etc.). The inlet needle also appears to be OK, but you never know with those things, so I was able to buy an OEM NOS from a marina in Michigan. Anyway, the new needle arrives and looks great, but no spring with it. I have the spring still attached to the old needle, but the thing is, the spring is completely compressed. The spring attaches to the tang / clip on the float, and the other end slides over a fitting on top of the needle.

My question is, does this spring need to be, well, "springy" in order for the float to rise properly and put some tension on the inlet needle, or is it there primarily to be used to help pull the needle out of the seat (which is actually part of the fuel bowl, not removable) if it is sticking? I checked the float level by turning it upside down, and it actually appears to be lifting too short of the lip of the fuel bowl (svc. manual says should be dead even with the top of the bowl). This would seem to be contrary to a flooding engine, if the float is too low - one would think if it was flooding the float would be set too high. So, is there any reason to have the spring more springy, or does this not particularly matter?

 

[Laddies]

Re: 25hp Merc Inlet Needle Spring?

The spring acts as a cushion to keep fuel from sloshing in the float bowl in rough or choppy water.

 

[Cordovakid]

Re: 25hp Merc Inlet Needle Spring?

OK, thanks Laddies - so if I am understanding you correctly, it should not make any real difference if the spring is tightly wound so it will not compress any further, so long as it will spring outwards to keep the needle from pulling out of the seat, correct? I just want to make sure the needle is seating firmly - have already done a short soak / spray with carb cleaner on the carb body, which would include the integral needle seat, and the needle is brand new. Fuel pump diaphragm / gaskets are also being replaced, as the diaphragm is somewhat stretched.

Any other possibilities I may be missing re: my flooding issue?

 

[Laddies]

Re: 25hp Merc Inlet Needle Spring?

The spring need to have a little spring to it, as the fuel slops around the float bowl the spring is supposed to keep the inlet needle from bouncing around and thus changing the fuel height in the bowl causing it to change the mixture.