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Engine Help => Kohler Engines => Topic started by: bodydropped72 on August 18, 2008, 11:37:20 AM

Title: k321 carb
Post by: bodydropped72 on August 18, 2008, 11:37:20 AM
Can someone tell me where i can get a carb with a manual choke my current carb has some kind of electric choke and i cant get it to work properly
Title: Re: k321 carb
Post by: Wheelhorseracer on August 18, 2008, 11:43:44 AM
Ebay.. Carb Search (http://shop.ebay.com/?_from=R40&_trksid=m38&_nkw=k321+carb&_sacat=See-All-Categories)

Or check out this site and ask some of the members
http://www.mytractorforum.com

Remember that you can use a #26 or a #30 carb on there as they are interchangable..
Title: Re: k321 carb
Post by: amcchevy1 on August 18, 2008, 11:46:51 AM
i wish i could get rid of my carb too. its on a 15hp kohler command, on my grass cutting walk behind. it has some type of spring on it and its constantly choking my mower.
Title: Re: k321 carb
Post by: bodydropped72 on August 18, 2008, 06:48:11 PM
here is a pic of my carb
Title: Re: k321 carb
Post by: Wheelhorseracer on August 18, 2008, 06:57:28 PM
Yep a #26 or #30 Kohler carb will bolt right in in place of that.. I pulled the emission Walbro off my Magnum and swapped on a #26 and what a huge difference it made.. plus it gave me the high speed adjustment...
Title: Re: k321 carb
Post by: 300xdeere on August 18, 2008, 08:01:01 PM
I believe carb does have the high speed you can see it on top...If its a stock mower just for cutting grass or some thing of that sort...then i'm sure you can get the choke plate/arm from a carb that has one that is manual but if its in some kind of racer/puller you can take the choke right out and fill the holes left behind and get a small amount of performance gains.
Title: Re: k321 carb
Post by: Wheelhorseracer on August 18, 2008, 08:40:13 PM
Yep.. I should have blown the picture up...

There is a high speed adjust on it.. I would think that would be a #26...

In my #26 I used the choke shaft and butterfly from an emissions Walbro that came with the engine.. it was exactly the same size just the Walbro uses different coding that isn't a true reflection of the venturi diameter like the Kohler carbs did..

According to my K-series manual that electric choke was an option on some models.. as most of the K series engines I have seen never had it..
Title: Re: k321 carb
Post by: bodydropped72 on August 19, 2008, 08:16:53 AM
to the right of the high speed adjustment is some kind of port not sure what its for but if the engine backfires gas come out of it on the carbs ive looked at on ebay none of them have this here is a pic of that side let me know if you dont see what im talkin about
Title: Re: k321 carb
Post by: 300xdeere on August 19, 2008, 08:43:35 AM
It is most likely a flowboal vent and or an external vent from inside the carb. All carbs should have them weather they shoot gas out of them not really to sure, i try not to look to close when their back firing :P
Title: Re: k321 carb
Post by: jim russell on August 19, 2008, 09:07:07 AM
hey do you guys know if the #26 and #31 will fit on the 15 hp kohler command ohv motors with no mods to the block or adapter plats. i want to get rid of the emmsinions carb
Title: Re: k321 carb
Post by: bodydropped72 on August 19, 2008, 09:42:11 AM
I think im just gonna swap out for a different carb...
Title: Re: k321 carb
Post by: Wheelhorseracer on August 19, 2008, 09:59:19 AM
I wouldn't swap carbs..

But that port is exactly where i drilled a vent hole.. it will go down into the bowl where there is a round rasised area in the casting..

You can still use the carb..

What i did was to tap the bowl vent into the airbreather at the front (if you look down the hole it will meet with the other port) and tapped it and screwed in a nylon bolt and cut off the head.. then the engine can only vent off the hole... which it what you have already..

So the factory did the mod for you.. I had to drill up through the the bottom on the carb inside the bowl to make that vent..

You should check to see if that vent goes directly into the float bowl.. if not it is a 10 second drilling to do it...

If your tractor starts well without the choke, then just take it off and run it..

They are very simplet the disassemble and rebuild and clean.. I wire wheel everything including inside the inlet and outlet of the carb to smooth out the casting flashes.. and it really helps the off throttle response..

Title: Re: k321 carb
Post by: Big daddy on August 19, 2008, 10:34:30 AM
 You are correct in that it is a vent hole. I have seen ones with the electric choke, but usually the little shut off solenoids are in the fual inlet passage. With the solenoid in the bowl area what will happen is if it is shut off and the motor is still running then the bowl will overflow. There are two vents on the K series carbs. one is located in the carb throat on the bottom of the opening< this one is the main jet vent, if this one gets plugged then it will surge rich on top end. The other is the one discussed here. If it is plugged then the fuel bowl will overflow (an atmospheric pressure thing). I agree that you might pull out the solenoid, cap it with a welch plug that you can get at any good hardware store for about $0.10, then drill a vent hole on the flywheel side of that boss. Hole size from 0.062 to 0.0937 should be plenty. I agree that if you are having problems with the choke then pull it out and replace it with a manual set up. These can be found lots of places.
In looking at your first picture I can see there is already a vent on the front of the carb opening about 2 o'clock. Again, you can still drill an external vent hole and will be fine. All our race carbs have an external vent hole.
Title: Re: k321 carb
Post by: Wheelhorseracer on August 19, 2008, 10:43:32 AM
I had to run an external vent and plug the one inside the breather because when I would hit bumps it would splash fuel out the vent tube and into the opening of the carb.. causing the carb to surge on the track.. or flood

Title: Re: k321 carb
Post by: bodydropped72 on August 19, 2008, 11:28:31 AM
That port does have some kind of solenoid with a plunger i take out the plunger? and replace it with a plastic screw and drill a small hole in the top of it?
Title: Re: k321 carb
Post by: Wheelhorseracer on August 19, 2008, 11:36:43 AM
That is exactly what I did..

Run a tab in the hole and buy a platic bolt and drill a hole through the middle... or if you want to continue to use the vent in the front of the carb you don't have to drill the hole.. and just plug the hole on the top.

I would be interested to see if you took the plunger out whether the hole goes all the way into the float bowl.

I will take a picture when I get home of my #26

Title: Re: k321 carb
Post by: bodydropped72 on August 19, 2008, 12:01:59 PM
i know it goes to the bowl i get gas out of it so i put a pin of some sort into the hole then cap it with a plastic screw? where can i find a manual choke shaft and lever?
Title: Re: k321 carb
Post by: Wheelhorseracer on August 19, 2008, 03:23:31 PM
Can the electric choke control just come off the shaft? then you can leave the shaft in place and add something to help you turn it when you need it..
Title: Re: k321 carb
Post by: bodydropped72 on August 19, 2008, 04:21:58 PM
Have not really looked at it yet will tonight would still like pics of that plug
Title: Re: k321 carb
Post by: bodydropped72 on August 19, 2008, 06:40:14 PM
were you gonna post pictures of that mod you did i would like to see what it entails thanks
Title: Re: k321 carb
Post by: Wheelhorseracer on August 19, 2008, 07:15:22 PM
(http://img.photobucket.com/albums/v302/GoldsackFamily/th_DSC00403.jpg) (http://img.photobucket.com/albums/v302/GoldsackFamily/DSC00403.jpg)

This is the vent I drilled up through the bowl and out the top.. you already have this hole.. I tapped it and screwed in a plastic bolt with a hole drilled in the center. I then just cut the head off.

(http://img.photobucket.com/albums/v302/GoldsackFamily/th_DSC00402.jpg) (http://img.photobucket.com/albums/v302/GoldsackFamily/DSC00402.jpg)

On the top right you can see where the old was. It used to go out in the air breather for venting.. but bouncy tracks would make the bowl push fuel out of this hole and the engine would suck it up. I tapped it and screwed in a plastic bolt then cut off the excess
Title: Re: k321 carb
Post by: bodydropped72 on August 19, 2008, 07:59:27 PM
im having a real hard time tryin to get this thing runnin it will crank about 15 seconds then pop and repeat. i have spark and fuel. wheelhorser i think im gonna plug that hole in the top completely i noticed there is another vent in the bottom of the carb throat would this hurt to do?  i think im loading up the engine i got it to run for about 30 seconds the other day and now nothin...
Title: Re: k321 carb
Post by: Wheelhorseracer on August 19, 2008, 08:13:34 PM
You might need to pull the bowl and check the needle and seat for dirt..

You pull the bowl, then slide the little pin holding the float in.. but keep your hand under it cause as soon as you remove the float the needle will fall out in your hand..

Take off the fuel line and blow some air through the fuel inlet to clear it out.. check the condition of the needle and if it seems worn then replace..

You can remove the high speed needle and the idle screw ( it is a small needle) then clean them up with a wire wheel.. ( count the turns to make sure they go back in the same place when you put them back in)

You can use a welder tip cleaner to clean the holes in the high speed jet.. usually a wire wheel will clean them up nicely though..

While the needles and idle screw is out blow air through the vents to make sure they are clean..

Reassemble and try it out again..

All of this should only take 15 minutes.. and can make a big difference..

How strong is the spark and when was the last time you set the point gap? 

Title: Re: k321 carb
Post by: bodydropped72 on August 19, 2008, 09:48:56 PM
never set the point gap, i blew out the high idle and low idle jets didnt do the fuel bowl though do that tomorrow..this thing came from an ol gen all i did when i got it was make sure it turned over other than that just short burst of running no longer than 30 seconds..
Title: Re: k321 carb
Post by: bodydropped72 on August 19, 2008, 10:33:03 PM
lookin at the pics of your carb you have 2 holes in the choke plate and i looked at mine and it has none could making holes make any difference
Title: Re: k321 carb
Post by: Wheelhorseracer on August 20, 2008, 06:20:54 AM
Maybe.. I would think you would want a bit of air to get through there..

You have to be VERY careful if you want to remove it.. the screws are brass and they strip and break easy..

You might have to file down your screwdriver so it fit's snug in the screw.. that will minimize the chance of it breaking..

Once the plate is off the shaft will slide out the side.. thee is two little "balls" inside the bore which holds the shaft at the location you choice when you put on the choke.. they normally don't fall out.. but just letting you know it's there..

When you get off the bowl have a good look inside for rust and make sure it is really clean..

When you unscrew the high speed needle and have the bowl off you can look up inside the shaft that goes up which holds the needle.. the jet is inside and needs to be clean and clear.. don't try to take out the jet inside ... most of the time they will not come out and you can wreck the casting if you try.. just make sure it is clean..

But the needle and seat is what you need to check first as it is the most common reason for a poor running Kohler carb.

Title: Re: k321 carb
Post by: bodydropped72 on August 20, 2008, 08:15:48 AM
thanks ill give that a try when i get home from work today. also gonna check my points gap.
Title: Re: k321 carb
Post by: Wheelhorseracer on August 20, 2008, 08:54:02 AM
Ya.. use some emery cloth to clean the points.. I prefer to use a non-metallic feeler gauge to check the gap.. but that's just habit from checking the points in my 1965 Chrysler..

Title: Re: k321 carb
Post by: 300xdeere on August 20, 2008, 10:03:38 AM
After reading on a little bit i don't think your motor not running has any thing to do with your carb this all sounds like a fly wheel key beeing sheared. Pull your fly wheel off i'm almost willing to bet its messed up. Because you said it was back firing out of carb, and that some times it would run for a few seconds, sounds like the flywheel is slipping into and out of proper timming.
Title: Re: k321 carb
Post by: bodydropped72 on August 20, 2008, 10:21:23 AM
Ill check it but im almost positive it has not moved
Title: Re: k321 carb
Post by: Big daddy on August 20, 2008, 10:33:39 AM
If it is a later model 14hp. motor then there is no ignition magnets inside the flywheel. It will be charging magnets only. Check and clean out your carb. really good, as you disassemble the carb. completely and flush out every orfice, check the idle circuit fuel holes. They will be on the backside of the butterfly on the same side as the idle air screw. Make sure they are not plugged. Make sure the vent holes are not plugged also. If the carb checks out OK, then you might replace the spark plug, or put a spark checker on the plug and if it runs good with the spark checker on, but will not run with it off then replace the plug. Something to think about. ;)
Title: Re: k321 carb
Post by: Wheelhorseracer on August 20, 2008, 10:39:23 AM
Sometimes if the condenser quits you will get a miss fire as too much energy is passed through the points.

You just go to a Kohler dealer and pick up a set of point and condenser... also if you do pull the points it's good to look at the condition of the push rod that activates the points to make sure it isn't worn. You can sometimes shine a light in the hole to check if the eccentric on the camshaft that the pushrod runs on is worn.. most of the time the rod would wear before the camshaft.

Since the timing is done by the points and not by magnetic pick-up on the flywheel the only issue of the K-key moving is that the balance of the flywheel would be off.

The plug gap will effect the timing.. you can actual read the timing through a timing hole on the tin using an inductive pick-up timing light but this is usually not necessary..

Title: Re: k321 carb
Post by: bodydropped72 on August 20, 2008, 01:41:49 PM
Would any condenser work like one from a distributor? there all basically the same right?
Title: Re: k321 carb
Post by: Wheelhorseracer on August 20, 2008, 02:05:14 PM
... ya they are the same as the one found in distributors. but sometimes they are a bit of a pain to get to work with the cap that goes over the points if they are not the one with the coated wire... sometime they will give you a condenser with a wire strap coming off of it.. ti is a real pain to get it to go out through the slot in the points cap ... you need to have the condenser grounded and that usually means fastening it to the engine block right beside the cap...

You can search on Google to see how to check a condenser.. but I haven't... if the points look burnt the condenser is probably bad... it takes the extra current away so that the points don't arc and wear themselves out.. when the condenser goes bad it eats up the points from all the arcing.. you can actually see it in the dark..
Title: Re: k321 carb
Post by: bodydropped72 on August 20, 2008, 07:13:22 PM
well i did notice the other day my condenser was just hangin around noticed it would spark to ground when tryin to fire it so i found the clamp for it intalled it onto the block and no change as for tryin to install it mine is right net to the coil it does not go into the points cap like someone else was saying earlier
Title: Re: k321 carb
Post by: bodydropped72 on August 20, 2008, 08:54:34 PM
Well i got it to run a lil longer tonight had to have the throttle about 1/2 way open with main set at 3 1/4 and low set at 2 1/2 really thinkin its a carb issue when it was runnin it was popping pretty bad not sure what else to do
Title: Re: k321 carb
Post by: Wheelhorseracer on August 21, 2008, 07:27:49 AM
What did the points look like?
Title: Re: k321 carb
Post by: bodydropped72 on August 21, 2008, 08:09:15 AM
they looked really good actually
Title: Re: k321 carb
Post by: Wheelhorseracer on August 21, 2008, 10:25:32 AM
OK.. that good to know.. and you fastened the condenser back tot he block?

I never thought.. but maybe the carb gasket has a leak and you are getting a vacuum leak between the carb on manifold?
Title: Re: k321 carb
Post by: bodydropped72 on August 21, 2008, 04:37:24 PM
All i know is that im gettin frustrated with it, it has compression fuel and spark i cant check the timing until i get it to run... not sure what else to do
Title: Re: k321 carb
Post by: Wheelhorseracer on August 21, 2008, 04:52:50 PM
.. have you adjusted the mixture screw at all.. you could be so far off with the screws that it will not start or stay running..

The initial setting from Kohler are the following..

High Speed jet: turn the screw all the way in until it bottom out.. then turn back 1 1/4 turns

Do the same with the idle screw...

The adjust from there... first move the idle screw then the high speed...

You will notice the revs go up then down... you want the fine balance between them..

You will need the engine warm and reved to about 3000 to properly set the high speed jet..

Here is some good reading material for you...

http://members.aol.com/pullingtractor/carbfuel.htm
Title: Re: k321 carb
Post by: bodydropped72 on August 22, 2008, 10:28:40 AM
Thanks ill look it over later today
Title: Re: k321 carb
Post by: bodydropped72 on August 22, 2008, 08:17:51 PM
well i finally got it to idle still sounds like its missing in a way also the throttle response is kinda sluggish sounds like its gettin overloaded kept adjust the high idle(main) jet but it really didnt seem to help that much. ive only got about 1 1/2 to 2ft of exhaust on it not sure if this is effecting it let me know your thoughts..also i read a little bit on that weblink..think if i did that boring of the main needle and closed off the middle holes in the needle it will do anything...
Title: Re: k321 carb
Post by: joshco84 on August 22, 2008, 08:20:00 PM
If you are adjusting the mixture screw and its not doing anything, there could be two problems i can think of off hand

1.  Are you adjusting the correct screw?

and 2.  It sounds to me like it is starving for fuel if you are turning the right needle.
Title: Re: k321 carb
Post by: amcchevy1 on August 22, 2008, 09:32:24 PM
if you're adjusting and it ain't changing then you may need to clean the carb. Have you checked your fuel? water can sneak in there if it has been outside.
Title: Re: k321 carb
Post by: bodydropped72 on August 22, 2008, 11:18:32 PM
fuel is new right out of the can...think its a jetting problem?
Title: Re: k321 carb
Post by: joshco84 on August 24, 2008, 08:32:31 AM
nope sounds like a dirty carb problem

Take it apart, these carbs are easy to clean.
Title: Re: k321 carb
Post by: Big daddy on August 25, 2008, 04:36:59 AM
If you are running pump gas in this motor then I would not redrill any of the jet holes in this carb. Look at everything else before you start changing the jet sizes. Double check the ignition wiring first, neg. coil wire goes to points, pos. wire to battery. Check for valve leakage, turn motor over by hand and listen to exhaust and intake openings for a slight hissing sound. Check float to make sure it has not gone bad, I have seen many Kohler floats start leaking at the solder joint on the float. Like was said earlier in this post, when adjusting for a mower or service application turn the motor to operating speed which is 3600 rpm, before adjusting the top/main jet. If it is a race motor then hold it wide open when adjusting the top/main jet, (just don't hold it wide open for too long!!). If you have the idle too fat it will overload the top end circuit, and will still idle OK. Adjust the idle screw clockwise until it starves for fuel then back it out a little, this will keep this from overloading the high speed circuit. Make sure your vent holes for the boal and main jet are not plugged. make sure there is not too much slop in the buterfly shaft and it is not sucking air through the shaft. If you start drilling out the jet and you are running pump gas or race gas you will overjet the carb, and will have even more trouble adjusting the carb.
Title: Re: k321 carb
Post by: bodydropped72 on August 25, 2008, 10:33:50 AM
Im using the engine in my golf cart so id say its between service and racing mainly be using it to cruise around in