Artic cat 500 in a box…well several boxes

[Streetmedik]

Ok friends. It is 90% back together. It starts... And I couldn't have done it without your help.  Thank you.

 

Now the next step.  Carb is leaking at the top of the bowl.  And it doesn't sit level. Should it be set level on the bike? See photos.

 

The other question is about the accelerator pump lever. Circled on one of the photos.  What does it attach to?  I have looked through the documents I was given links to and searched google.  Can't find an answer.

 

I appreciate all the help.

 

[Cj Winds]

The lever does not attach to anything. If carb is leaking at top of bowl then the bowl gasket is prolly leaking.

[Streetmedik]

Just now, Cj Winds said:

The lever does not attach to anything. If carb is leaking at top of bowl then the bowl gasket is prolly leaking.

Why would they use a carb with an accelerator pump and not use it?  Don't get me wrong, absolutely not doubting you. Just don't understand the company's thought processes.

Where is the best place to buy a carb kit?

[Cj Winds]

I believe its a fuel primer. Very few utility atvs have accel pumps on the carb.

[Streetmedik]

As can be seen in my last photos. The carb is not sitting level. Is it normal and correct for it to be “slanted” so that the bowl seam is not level?

 

I have been searching Google to try and find a photo of the carb mounted on the 4wheeler so I could see if it should be level or not. However, I can't find a good photo.

[Cj Winds]

It seems off but hard to tell. Did you install the carb boot that attaches to the cylinder head or was it already attached? Is the carb completely pushed in the boot?

[Streetmedik]

It is fully seated as far as I can tell.  The boot was already bolted onto the cylinder. I just assumed it was mounted correctly.

[Mech]

In the manual the carby looks like it's on an angle, and I've seen plenty of bikes that did have it's carby at an angle. I'd guess you need a new rubber seal for between the float bowl and body, or the seal's misplaced/distorted, or the float level is wrong, or the float/bottom cover's distorted.

In the pictures it doesn't look like there's anything attached to that part you have circled either.. Are you sure the accelerator pump doesn't work off vacuum? It could be that when it's idling the diaphragm gets sucked down, then when you open the throttle it goes up pumping fuel..  That's a fairly common system.

Edited March 1, 2022 by Mech

[Streetmedik]

1 minute ago, Mech said:

 

In the pictures it doesn't look like there's anything attached to that part you have circled either.. Are you sure the accelerator pump doesn't work off vacuum? It could be that when it's idling the diaphragm gets sucked down, then when you open the throttle it goes up pumping fuel..  That's a fairly common system.

It is mechanical.  And if I pull up on it, it squirts a mist from the nozzle in the intake side of the carb.  I spent 2 days unclogging that nozzle.  Then to learn it isn't used. By time I get this thing finished, I am afraid I might want one myself.

[Mech]

Oh ok. I haven't seen one like that. It might be that they use the pump on a two wheeler, but don't think they need it on a quad. There is another system built in to serve as an enrichener during acceleration. The pictures in the manual it doesn't look like there's any linkage or anything that your pictures don't have. Does that part you have circled in the last photo move with the throttle does it ? In the manual, there is a diagram and it shows something near screw 29, do you know what that is ? It looks a bit like a linkage.

Perhaps just try it and see if it goes ok..

Here's a picture of a carby off a DR400.. perhaps you are meant to have a linkage like this, except the pump plunger is different.

That's the nearest I've got to your carby..  similar pump at least !

[Mech]

I just noticed you say that it pumps if you pull up on the pump's linkage, so does that mean you have the spring above the diaphragm ? And is the push-rod attached to the diaphragm somehow ? It doesn't look like it's attached in the pictures I've got.

In the DR400 that plunger gets pushed down, and the spring is underneath the diaphragm..

In the arctic cat and the DR manuals the spring is shown above the diaphragm in the exploded view, but in the DR description of operation later on it shows the spring as being below the diaphragm, and says the plunger gets pushed down to squirt the fuel.

If you put the spring under the diaphragm would the plunger rod perhaps touch the throttle somehow then ?

[davefrombc]

9 hours ago, Streetmedik said:

It is mechanical.  And if I pull up on it, it squirts a mist from the nozzle in the intake side of the carb.  I spent 2 days unclogging that nozzle.  Then to learn it isn't used. By time I get this thing finished, I am afraid I might want one myself.

It may be a "primer".  Used on some applications to  give a shot of fuel  mist to enrich the initial  fuel  charge  for starting.

[Mech]

Yeah that's what I'm suspecting too Dave.. The owners manual should describe that if it's the case.

[Streetmedik]

I am guessing the accelerator pump is simply not needed on this 4 wheeler.  I was able to get it to start and throttle up just fine.  Need to get a carb kit as it leaks like crazy at the bowl top.   

 

So, while I am searching for a carb kit to order, I will tackle the brakes.  Calipers are nasty. Perhaps I'll tear them down tomorrow.  For now, I'm tired.  Worked on rebuilding the Kubota tractor that we use at work.    Seems odd that since I retired from ambulance work... Everyone suddenly thinks I am a mechanic.

[Mech]

I had a read and that is a primer pump for extreme cold.

If the float level is set correctly the fuel shouldn't get to or leak out of the top of the bowl. If it's idling and the fuel is getting shaken up then there might be some small amount of fuel getting to the top, but it should hardly cause any leak, just a bit of wetness. I'd take the bowl off and recheck the float operation and level. I'd inspect the rubber seal isn't too flat and if it's still reasonably round in cross section I'd try using it again. If the leak is bad, you've probably not got it located in it's groove properly allowing the bowl to be held away from the carb body. If you've tightened the screws real hard trying to stop the leak you may have distorted the bowl. Give it a quick rub on a bit of wet and dry paper on a flat surface to check it's still flat.

Those rubber bowl seals usually last for years, but sometimes if you dismantle the carby and have it apart for a while the rubber distorts and can be hard to get back into place as you put the bowl on. The way to get the bowl on with the rubber seal in the right place is to fit the rubber in place as much as possible, then use a feeler gauge(or two) to press/hold the last bit down into it's groove while you fit the bowl. Once they are refitted in their groove properly, they normally seal even if they are old and hard.

[Streetmedik]

This one is very hard and as flat as a board. The float moves freely. I'll see if I can find something that tells me the correct float height. 

 

In looking on parts sites for a carb kit, it seems in 2003 artic cat made several variations of the 500.  How can I know which one I actually have in front of me?  I tried search8ng for the VIN. Not much help.  Some sites said it was a 2003 Caterpillar, some said Massie Furgason. I'm pretty sure it is neither of those.

6 versions of the automatic transmission Artic Cat 500.

[davefrombc]

There should be some identifying numbers on the carb itself  you should be able to use  determine which one it is and get the specs for it

 

[Mech]

Yup there should be a number, possibly CDK 36 or CDK 42.. The numbers refer to the venturi size.

If you can't find the number, look at photos. The overhaul kit will fit several different venturi sizes as long as it is a CDK. If you google Keihin, which is the make I think, you might find it.

[Streetmedik]

These photos were before I cleaned it, so please excuse the grime.

[Mech]

Yeah that dot punched number will be the one I'd think.. It describes the exact setup, options, jet sizes etc There should probably be another cast number telling you the venturi size, but maybe not. That punched number should find you the parts you need.

[Mech]

Arctic cat manual says it has a CVK36.. CD and CV are the same thing.. Constant depression  or constant vacuum...

[Streetmedik]

Thank you 

[Mech]

https://www.joom.com/en/products/5d8596348b45130101460664

 

Look right ?

You're welcome.

[Streetmedik]

1 minute ago, Mech said:

https://www.joom.com/en/products/5d8596348b45130101460664

 

Look right ?

This is what I get.

[Streetmedik]

I might drive to Tulsa to an Arctic Cat dealer and see if they have a carb kit in stock.

[Mech]

Oh ok. We had a similar problem the other week, turned out to be browser security settings. I use linux and don't have security.. The kit they were advertising was $22 kiwi.. about fourteen bucks yanky I think.

Maybe... http://tiny.cc/sy3puz

[Cj Winds]

The kit for a 2003 AC 500 is 26-1059

2000-2002 uses 26-1061

2004 uses 26-1058

Make sure the vin's 10 digit is a 3 to symbolize 2003 model year

[Streetmedik]