johnson 15 horse carb question

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doc1976

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1985 johnson 15, trying to figure out if the carb is supposed to have a removable bushing/seat for the idle/low speed mixture screw or if the seat is machined into the carb casting. One exploded view diagram from a parts site shows no removable seat, but the instructions with the rebuild kit shows one. there does not appear to be one on my carb but I'm worried that the PO may have lost it on a rebuild attempt. thanks in advance.
 
it's aftermarket. I am used to carb kits covering multiple models and usually not needing all the parts, but the fact that it made reference to it in the instruction sheet included got me wondering. I was able to get a flashlight in the bore to get a look at the needle seat area and it does not look to be machined but it is a pretty small bore so its hard to tell. I was hoping someone here has a little intimate knowledge of these carbs to put my mind at rest before reassembly.
 
No removable seat for the mixture needle but there is a small nylon bushing on most metal top carbs. Not sure about the plastic carbs on the nylon bushing.
 
I assume you are referring to the "packing" for the needle? the small round one with the key on one side to keep it in place?
 
doc1976 said:
I assume you are referring to the "packing" for the needle? the small round one with the key on one side to keep it in place?

There might also be a nylon bushing that goes over the steel part of the needle, not related to the red keyed packing. Just go on one of the sites that has exploded views. You will see it. Make sure to check to see if there is one there now or not in the carb.
 
there was nothing on the needle, or in the bore it goes into, but I will double check an exploded view for the model to be sure there isnt supposed to be. thanks for your help, greatly appreciated
 
20170318_225750.jpg20170318_225722.jpg20170318_225701.jpg Hope you can read and see these OK. These are from my Clymer manual. OMC 2-40hp. 1973-1990. Looks like these are the relevant pages. Let me know if you need anything else. No idea why they are on their sides as I posted them in portrait mode. Maybe download them and rotate or lie on a bench to view.
 
well i got her running. needs a little fine tuning still a little rough at idle. thanks for the help
 
doc1976 said:
I assume you are referring to the "packing" for the needle? the small round one with the key on one side to keep it in place?


Doc, that red bushing with the "key" is the only thing on my 15 with regards to the Low Speed needle.


CMOS
 

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