50hp Johnson carb swap?

[Keyboardman]

Hi guys, been having no luck in finding carbs for my '74 50hp Johnson. I did find a set of carbs from an '81 model. Will they work on my engine or should I keep looking for originals. Thanks

 

[gm280]

KBM, you could check the part numbers online and see if they are the same. Other then that, it is a gamble. I take it you don't have any carbs presently. Otherwise you could rebuild them. So keep looking and see what other post here. JMHO!

 

[Keyboardman]

I do have the original carbs but the threads for the low speed idle needle are messed up. I can't see anyway of tapping/cleaning them out. Been going nuts looking for at least an old body I can rebuild. I'll try checking numbers. Thanks

 

[oldboat1]

Didn't you have a couple of those motors? Maybe confusing you with another poster.

Are the needles OK? If you have a threading issue with one or both of the carbs (housing threading damaged), you could try epoxy as a last resort. You would wrap the needle with a couple of layers of plastic wrap, then coat with thickened epoxy. Insert the needle and let the epoxy set up a bit. Periodically twist the needle in and out slightly just to make sure it's not sticking. When the epoxy is set, back the needle out. You should be able to run the needle back into the newly threaded housing. I would do this with the expansion plug removed so you can see the needle fit. Additionally, I would put the plastic retainer in place (that retainer "valve") when fitting the needle to make sure it is correctly centered.

Again, last resort.

[Edit. Are you sure there aren't washers jammed up in the housing? Maybe the threads only seem to be buggered up -- seems very unlikely that both carbs would be a problem. The needles are not necessarily snug, if that's your concern. Needle washers will give a snug fit/feel.]

 

[Keyboardman]

The bottom carb has the problem. The needle itself is in good condition. The needle will go in about 3/4 of the way then it gets super tight to where I can't get it all the way in to seat. Looking in the housing, I see nothing to cause it to bind up. Wish I knew of a way to chase the threads,,,,,,

 

[flyingscott]

your carbs show a needle bearing on the low speed hole, look down the hole and see if you have more than one in there. They are hard to see and plastic you may need to remove it or replace it.

 

[oldboat1]

You want to avoid breaking off the point of the needle, or messing up the orifice where the needle seats. With that in mind, I would pull off the plug on top of the carb to see in there. First, you may find the point of another needle broken off in there -- would need to gently push it out. Second, you want to be able to see whether or not the needle is seating, and will be able to do that with the plug removed. Assuming the orifice isn't jammed, you may just be running up against that bearing (plastic) or washers (fiber or rubber). Checking from the top to see progress, you can lube the needle a bit and see if you can gently screw it through the washers or bearing(s). If you can grip it with the threads, you might be able to pull out whatever is in there, assuming it's not something metallic. First check for a broken needle.

 

[rookie456]

No Title

I have a set off of a 72 50hp. 313355 D2 stamped on the bottom of the bowl. Mod EDIT: please PM Rookie for any further details

 

[Keyboardman]

Thanks guys for the advice. I found a set of carbs from a '73 evinrude 50 which are the same bodys. Will have to switch around a couple of linkages but that's no problem.