needle valve bearing??

[jwilkey84]

I took apart my carb again so I can be for sure that my problem is not the carbs, and the only question I have is concerning the needle valve bearing. My rebuilt kit included a new one, but I don't think there was one there when I took it all apart. Is this piece necessary? I can't seem to figure out how it goes in anyway, I can poke the end of the needle through it, but I cant start the threaded part of the needle valve. The only thing I can think of is that I am not pushing on the needle valve hard enought to get the threads started, but I hate to bend something or mess up the threads. This is on a 72' 20hp johnson.

 

[bgbass.1]

Re: needle valve bearing??

I looked in my manual I dont see one there kit could be for more than 1 carb.

 

[Joe Reeves]

Re: needle valve bearing??

If by "bearing", you're speaking of a RED bushing (part #315232), that item is designed to prevent the needle valve from moving via engine viberation. Without it, it would be impossible to keep the carburetor adjusted.

Install that bushing into the top of the carburetor, then install the needle valve. It will be necessary to apply a slight bit of force initially when starting to thread the needle valve thru it.

When time permits, visit my store (copy/paste) at: stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store

 

[F_R]

Re: needle valve bearing??

There are actually two plastic parts related to the needle. The 315232 retainer that Joe speaks of and the 314166 bearing. The 315232 is outside where the needle enters the carb, is round with a key-tab on one side. That part is a force-fit as the needle screws into the soft plastic and as Joe said it keeps the needle from turning from vibration. The other plastic part, the 314166 bearing is sort of like a tiny funnel and goes way deep in the hole. You really can't see it in there, but it is there--or at least needs to be there. It actually is a seal that prevents sucking air around the needle. I made myself a tool to hook them out. Some people have reported that a drywall screw works. Just push the new one in with a straight punch or rod.

 

[jwilkey84]

Re: needle valve bearing??

the part number I am refering to is the funnel shaped plastic piece, part #314166. It goes deep in there? I don't think I removed one when I worked on the carb initially. Would I be able to see it if it were in there?
So do you push it all the way to the back with the punch and then screw the needle valve in? Or should I push it part way in and then let the needle valve push it the rest of the way in. Either way I need to use a punch to get it at least beyond the start of the threaded part so the needle valve has something to thread into, right?
How much effect would this have on the motor running, because it runs like crap and I am trying to figure out why. The trouble I have is I don't know how this motor ran when it was last used, so I have nothing to go by. But I know it runs like crap, and gets worse if you give it throttle. You are lucky if you can get above idle without it dying. Compression is good, spark appears good, gas line if fine, primer bulb keeps hard, carb is rebuilt, impeller is new. The motor shows no signs of abuse or heating, so in my mind it will run good once again! Thanks for all the help.

 

[stl]

Re: needle valve bearing??

I just went through this a few months ago with my 73 18 hp Evinrude. The old one did not come out so I did not put a new one in. The motor ran like crap. Then i noticed that bushing in an exploded diagram. I took it apart again and I was able to remove the old one. If I remember correctly it was in pieces. I used a drywall screw and a small wire with a hook on the end to get it out. Then cleaned a blew out the passage real well. I think I used a small finish nail to gently seat the new one. A few light taps on the sharp end of the nail set it nicely. This definetly made it run better. That funnel shaped bushing keeps air from coming in around the needle. Keeps us posted.

 

[jwilkey84]

Re: needle valve bearing??

so how far do I put it in?

 

[Joe Reeves]

Re: needle valve bearing??

That forward small funnel shaped bearing...... I remove the old one with a small tap that will engage the bearing without touching the carburetor wall.

To install, making sure that one isn't already in there, simply place it over the end of the needle valve and it will seat itself.

 

[jwilkey84]

Re: needle valve bearing??

OK, I'll try that. I have tried that and was afaraid of pushing too hard, but apparently it must take a little force to get everything started.

 

[F_R]

Re: needle valve bearing??

A bad funnel bearing will allow it to suck air past the needle which will mostly affect idle. It will have little if any effect on higher speeds. But go ahead and replace it anyway.

Are you positive that the high speed orfice plug is clean? It must be absolutely clean with not a trace of crud or varnish in it. All of the fuel for anything above idle speed is metered by that orfice.

 

[jwilkey84]

Re: needle valve bearing??

if you are referring to the main jet, then yes I am for sure that it is as clean as the day it left the factory. Just so we are on the same page, you are talking about the main jet located behind the bowl drain plug, correct? I have cleaned this carb 3 times now and installed a complete rebuild kit, checking all the passageways, blowing compressed air and carb cleaner through all the passages, and replacing all the plugs on the carb. The only thing I havent done is this bearing.

 

[Joe Reeves]

Re: needle valve bearing??

There is a scribe mark on the cam (attached to the armature plate) that slides against the throttle cam roller.

The carburetor throttle butterfly should just start to open when that scribe mark is aligned dead center with the roller..... not before or after. If adjusted otherwise, weird things will happen including having the engine die out when throttle is applied.

(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

Note: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

When time permits, visit my eBay store (copy/paste) at: stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store

 

[F_R]

Re: needle valve bearing??

if you are referring to the main jet, then yes I am for sure that it is as clean as the day it left the factory. Just so we are on the same page, you are talking about the main jet located behind the bowl drain plug, correct? I have cleaned this carb 3 times now and installed a complete rebuild kit, checking all the passageways, blowing compressed air and carb cleaner through all the passages, and replacing all the plugs on the carb. The only thing I havent done is this bearing.

Yep, that's the one I was referring to. It was just a thought, especially since so many people miss it, or the importance of it being very clean. Sounds like you are good though.

 

[jwilkey84]

Re: needle valve bearing??

i got the new needle valve bearing in and the old one out. I think the problem was that the old one was not in one piece, there was even a small chunk in the hole that the needle goes in, that I had to force out backwards with carb cleaner and compressed air. I got it to run tonight and it seems better, though I couln't let it run long as no water was coming out. I don't know if this motor has a tstat, but that is my next issue.

 

[ronsgto]

I know this appears to be an old post but I have similar problems will not run at high RPM gets real rich. Valve bearing is missing. I pinched off fuel line 30 seconds or so latter I could get full RPM till it ran out of fuel. Any ideas would be great.

Thanks

Ron

 

[GA_Boater]

I know this appears to be an old post but I have similar problems will not run at high RPM gets real rich. Valve bearing is missing. I pinched off fuel line 30 seconds or so latter I could get full RPM till it ran out of fuel. Any ideas would be great.

Thanks

Ron

Please start a new thread.