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K482 Carb--Is This Repairable?

bolens 1886 k482 kohler k482 carburetor broken needle valve

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6 replies to this topic

#1 Utah Smitty OFFLINE  

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Posted July 26, 2013 - 11:52 PM

 I just bought a Bolens 1886, and was trying to get the engine to stay running without pouring gas down the intake... I pulled the fuel pump--the check valves were gunked up, so I cleaned them as best a could, and also checked out the diaphram--seemed to be fine.  Put it back on.

 

When I disassemble a carb to clean it, I always run the needle valves in--carefully, and count the number of turns, so I can be close when I reassemble it.

 

The long needle valve that runs to the jet in the middle of the fuel bowl came out fine, though it is bent a little; the idle mixture needle valve?? the one between the throttle plate and the manifold, came out also.  However, there was a tapered portion to the valve, but just a blunt end.  Also, I couldn't get any carb cleaner to go through the hole that the valve screws into.

 

I looked inside the bore, and this is what I found--look just above the ball-bearing in the flange at about 5 o'clock.

 

BROKEN NEEDLE VALVE.jpg

 

 

 

The small, tapered end of the valve broke off and is protruding through the bore...

 

I tried to tap it back down-- no luck.... I tried squeezing with a pair of needle nose pliers-- it just broke off and that's that.

 

Is there any fix for this????

 

Thanks,

 

Smitty



#2 chris m OFFLINE  

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Posted July 27, 2013 - 12:15 AM

Well I can say I have never had that happen to me yet.

 

But if it where mine I would start by heating the area around the needle valve and try pushing it out 1st with like a small 90 deg dental pick or even try pushing with a flat screw driver. I think just taking your time and even soaking it with PB blaster, you will eventually get the piece out.

 

If it still didn't want to come out I think I would try drilling it out with a small manual style hand drill, they look like a pen with a small collet on the end. then you could get the remainder of the brass out with a small torch tip cleaner.

 

What ever you decide, Good luck!


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#3 Utah Smitty OFFLINE  

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Posted July 27, 2013 - 01:07 AM

Well I can say I have never had that happen to me yet.

 

But if it where mine I would start by heating the area around the needle valve and try pushing it out 1st with like a small 90 deg dental pick or even try pushing with a flat screw driver. I think just taking your time and even soaking it with PB blaster, you will eventually get the piece out.

 

If it still didn't want to come out I think I would try drilling it out with a small manual style hand drill, they look like a pen with a small collet on the end. then you could get the remainder of the brass out with a small torch tip cleaner.

 

What ever you decide, Good luck!

 

Thanks, Chris.  I hadn't thought of using a torch and heating it up a bit.... if I'd tried that first, I might not have the problem I have now...

 

Smitty


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#4 Utah Smitty OFFLINE  

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Posted August 08, 2013 - 09:06 PM

Well, I got this repaired.... I think.

 

I make a bushing out of hard plastic to just slip fit inside the threaded bore for the needle valve. I used my mini lathe and turned it to size, and also drilled through the middle with a .042" drill.  I then chucked a .040" drill in a small drill and used the guide to center it and drilled down through the old needle valve--it wasn't coming out any other way.

 

I wasn't careful, and ended up breaking off the drill bit in the carb...... grrrrr!!  Then I remembered some carbide dental burrs my dentist had given me years ago.  One of them had a profile very similar to the idle adjustment needle valve.

 

I carefully drilled down into the bore with the carbide bit and my dremel... I actually drilled out the old bit.  and ultimately came through into the throttle bore... It was a few thousandths off from the old needle valve--hopefully it won't make a difference.

 

I bought a new needle valve from Tulsa Engine Warehouse, which came today.

 

I inserted the needle valve and carefully (there I go, using that word again!!) screwed it down until it was touching.  I could see the end of the valve in the hole, but it wasn't quite centered enough.

 

I drilled a little more with the carbide bit, but using a small hand drill and making careful turns... a sliver of brass about 1/4" long came out of the bore and the needle valve could then screw down all the way.

 

The hole's a little larger than before... I hope I can get it to work, otherwise I gotta find another carburetor...

 

I'll let you all know how it worked out after I get the carb assembled and installed.

 

Regards,

 

Smitty



#5 Utah Smitty OFFLINE  

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Posted August 11, 2013 - 09:58 AM

Well, I got this repaired.... I think.

 

I make a bushing out of hard plastic to just slip fit inside the threaded bore for the needle valve. I used my mini lathe and turned it to size, and also drilled through the middle with a .042" drill.  I then chucked a .040" drill in a small drill and used the guide to center it and drilled down through the old needle valve--it wasn't coming out any other way.

 

I wasn't careful, and ended up breaking off the drill bit in the carb...... grrrrr!!  Then I remembered some carbide dental burrs my dentist had given me years ago.  One of them had a profile very similar to the idle adjustment needle valve.

 

I carefully drilled down into the bore with the carbide bit and my dremel... I actually drilled out the old bit.  and ultimately came through into the throttle bore... It was a few thousandths off from the old needle valve--hopefully it won't make a difference.

 

I bought a new needle valve from Tulsa Engine Warehouse, which came today.

 

I inserted the needle valve and carefully (there I go, using that word again!!) screwed it down until it was touching.  I could see the end of the valve in the hole, but it wasn't quite centered enough.

 

I drilled a little more with the carbide bit, but using a small hand drill and making careful turns... a sliver of brass about 1/4" long came out of the bore and the needle valve could then screw down all the way.

 

The hole's a little larger than before... I hope I can get it to work, otherwise I gotta find another carburetor...

 

I'll let you all know how it worked out after I get the carb assembled and installed.

 

Regards,

 

Smitty

 

Well, I got the carb put back together, had the idle screw at about 1 turn and the high speed screw at 1 1/2. I started 'er up.  The engine fired right away and ran.  I pulled the throttle back to idle, and it ran a little rough, so I adjusted the idle mixture out and it got worse. So I turned it all the way in--still ran, but rough, so I split the difference at about 1/2 turn and she ran fine.

 

If I had this to do again, I would probably use the old screw as the guide-- it actually screws into the bore, and the brass wouldn't waller out (that's a technical term) as much.  You'd need to be careful to pull the drill back and let the chips clear.  Also, when you've drilled it out you'd still have to get the broken part out... it may fall out at this point, or it may need to be reamed out with a tapered bit with the same profile as the original needle valve---it helps to have a new one on hand for comparison.

 

Not many people have commented on this, so I hope it was helpful.

 

Smitty


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#6 olcowhand ONLINE  

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Posted August 11, 2013 - 10:56 AM

You did good!  Patience is the key with things like this, and you had the patience.  :thumbs:


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#7 Guest_gravely-power_*

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Posted August 11, 2013 - 11:00 AM

I knew you would drill it out as I have done it several times. It should be OK as the needle is tapered and will close the orfice accordingly.

 

Good job.


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Also tagged with one or more of these keywords: bolens 1886, k482, kohler k482 carburetor, broken needle valve

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