1983 Johnson 2hp high speed nozzle gasket question

[smallblock]

I am rebuilding the carb on this Johnson 2hp. There is a gasket that goes over the high speed nozzle(more like a think washer). The one I recieved for this(0302984) is larger in diameter than the old cork one. If I use this gasket it will just end up floating around in the fuel bowl,it doesnt fit snug...Is there a reason for this size difference or did I just get a dud?? Do I really need this gasket, it seems kind of useless. Any thoughts on this will be appreciated...thanks.

 

[cajuncook1]

Re: 1983 Johnson 2hp high speed nozzle gasket question

I am rebuilding the carb on this Johnson 2hp. There is a gasket that goes over the high speed nozzle(more like a think washer). The one I recieved for this(0302984) is larger in diameter than the old cork one. If I use this gasket it will just end up floating around in the fuel bowl,it doesnt fit snug...Is there a reason for this size difference or did I just get a dud?? Do I really need this gasket, it seems kind of useless. Any thoughts on this will be appreciated...thanks.

The gasket you are inquiring about is called a boss gasket(if am correct) and it is necessary. It should not be loose and floating, it should be somewhat snug.

The part number 0302984, you stated is the boss gasket that fits around the high speed nozzle. The super-ceding part number is 0331181 item #21 in the diagram. You might want to call the supplier and explain the issue.

Here is link to read to how adjust your carburetor...compliments of iboats.

http://forums.iboats.com/showthread.php?t=167352

Good luck my friend,

cajuncook1

 

[smallblock]

Re: 1983 Johnson 2hp high speed nozzle gasket question

Thanks cajuncook for your response. I mean no dis-respect but am looking for a more technical response. I have the part numbers and diagrams. I need to know if this gasket is absolutely neccessary and what exactly it does and why the one I ordered is over sized.

 

[cajuncook1]

Re: 1983 Johnson 2hp high speed nozzle gasket question

The boss gasket is suppose to be there, if it was not necessary, it would not have been put there in the first place by the engineers of the Evinrude. As for why the boss gasket in the carb kit you order is over sized, all I can say there is human error involved and the wrong gasket was incorrectly placed in there. My advice is to call the place you ordered the kit from and explain the oversized boss gasket and see if they will send you a replacement gasket.

As for the exact technical specifications of the gasket and an explanation of the fluid dynamics of fuel delivery of this specific piece of the carburetor, I sorry I don't have that information. I will tell you that carburetors are very finicky, they don't work well if their missing parts or dirty. Just my penny's worth of advice.

Good luck with your motor!

cajuncook1

 

[smallblock]

Re: 1983 Johnson 2hp high speed nozzle gasket question

Thanks Cajuncook. Im just confused because I have read other threads similar to this one that the gasket in question was said to not be needed and in fact other similar carbs have been produced without this gasket. Im just looking for an explanation of what this gasket does. It just doesnt seem to have a job in there. Technically unless its there to keep air surging up the threads of the nozzle it doesnt do anything because if there is gas up at that level the motor wouldnt be running...I have contacted the company about the gasket and am awaiting a reply. Sucks because I waited ten days to get the first one....Thanks for your input....

 

[catfish3]

Re: 1983 Johnson 2hp high speed nozzle gasket question

I realize this is off topic. But for someone else searching about boss gaskets and yours was like mine i.e. looks like it is to tall for the carb bowl to fit snug. The gasket will work. It will smash down to make a good seal when the bowl is screwed to upper part of carburetor.

 

[kbait]

Re: 1983 Johnson 2hp high speed nozzle gasket question

I have forgotten to install that 'boss' gasket before. It IS essential, as carb will flood the motor badly w/o it. I have also used an o-ring from the hardware store to replace a bad one (didn't need a full kit). Worked fine. I just brought the nozzle to the store and matched one up. It smashed slightly to seal, and wasn't so bulky that the bowl wouldn't snug to it's gasket too. Good luck!

 

[F_R]

Re: 1983 Johnson 2hp high speed nozzle gasket question

Thread is nearly a year old, hopefully he has it fixed by now. But as for the "why", the gasket keeps fuel from bypassing the needle valves/orifice.

 

[boobie]

Re: 1983 Johnson 2hp high speed nozzle gasket question

The gasket keeps air from getting into the high speed nozzle and messing up your high speed mixture be it fixed or adjustable.