Thread: Has anyone tried these?
07-20-2007, 08:37 PM #1
Has anyone tried these?
Saw this on ebay and it seemed interesting. Has anybody heard, seen or used these before? If so, what did you think of them or what have you heard about them. Thanks!!
07-20-2007, 08:52 PM #2
I have not used them, but I have had a rather long email conversation with the guy. Sounds interesting, but I can't use them on the application I wanted to use them on because the carbs are parallel mounted.
Here's the core of it, copied from my email.
Now that I know you are technical (You woudln't beleive the intellect of some of these jackasses that write to me), I can explain further. There is no concern about supplying too little fuel, the only concern woudl be too much fuel if anything. As a rule, most watercraft fuel pumps (Both carb mounted and remote) supply way more fuel than is needed. That's why many skis have a restriction in teh fuel return line, because the strong pumps just pumped it all back into the tank instead of keeping the proper amount ready for the carb.
Now, you are correct, there is a vent hole in the plate allwoing the atmosphreic pressure in. This needs to happen, because it is the low pressure area behind the diaphragm (After fuel is used by the engine) that allows the higher pressure on the other side of the diaphragm to push in, and open the needle. Fuel then enters the fuel chamber again. So, this plate's adjuster screw does contact the rivet on the center of the diaphragm, and pushes it back into the carb body, further than it would be under only atmospheric pressure. This does limit the diaphragm's travel like you say, but it limits it moving OUT, not in. This means that you will always have enough fuel, if not more than enough. That's why you have to adjust it in 1/4 turn increments only, to prevent flooding. The bottom line, is that the fuel chamber is filled less than normal, but far more often. It is a more constant supply of the correct amount of fuel, instead of the diaphragm opening WIDE open, taking on a LARGE amount of fuel, then running close to dry before the diaphragm opens up again. The adjuster screw means it is opening and closing far more often, and allowing a much more controlled amount of fuel into the chamber.
Hope this helps;
07-21-2007, 07:47 AM #3
What Its Changing Is The Set Height Of The Needle Pivot Arm,or More Exact The Amount Of Gap Between The Dia Button And The Needle Arm Pivot Button.the Set Height On Polaris Domestics Is .060.this Setup Allows You Change The Gap Which Gives More Movement To The Pivot Arm Or Less.does Nothing To Change Pop Off Pressure Or Spring Pressure,would Probably Work Good On A Single Carb Setup For A Twin Motor
Last edited by TxPro1200; 07-21-2007 at 08:51 AM.
07-21-2007, 11:01 AM #4
Yeah that's what I thought which made me wonder how he gets by saying what he does on his auction discription. Guess I'll stay away from that one.
Doug, I just got a PM from a guy looking for a throttle shaft for a twin carb setup. I told him to send you a PM as you might have a spare one around with all your carb stuff.
Last edited by 32DegH2O; 07-21-2007 at 11:03 AM.
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