Newbie needing help on 340/22 with walbro

[gerkendave]

Dug out dads old 400 and had low compression in one cylinder. After a tear down I found a bad rod bearing and broken piston skirt. Sourced a parts 400 with the 340/22 and tore it down cleaned it up put in new crank seals and a full gasket kit. I'm using the walbro that came with it ( old sled had a bendix), previous owner had already put a rebuild in the carb. Thing starts great with the choke and will idle with half choke on but will die with choke off. Also it will just bog and die when taking off unless I continually pump the throttle. Once moving it runs great but as soon as you stop moving it will die. I'm stumped. Help please!

[Matt]

Do you have the idle set screw up high enough? Then adjusted the low speed screw? If that's been adjusted, it's probably time to go through the carb again. Get a fresh diaphragm/gasket kit. Make sure all the tiny passages are clear. Make sure you set the metering lever - there are usually instructions on how to do this that come with the diaphragm kit.

[gerkendave]

Thanks for the tip. After pulling it apart I see someone had previously broken the metering lever. It is now broken again. Any where to get one for a wra-31 carb? Found a couple on eBay one is part #WLB-166618
and doesn't say what carbs it will fit. The other one is part # 166-48-8 and says it will fit WA & T models. Will either one of these work or do you know where I could find one?

[Matt]

No, those don't look right.

[gerkendave]

Any idea where one can be found. I see on the tech page it shows that included in a rebuild kit but not finding where to get a rebuild kit.

[Matt]

This is what it looks like, and he's using a throttle/choke plate to measure the height:



Full topic on rebuilding a Walbro:
http://vintagesleds.com/bs/index.php?topic=49980.0

Edit: I posted the wrong photo.

[gerkendave]

Haha well I wished my metering lever looked that nice. Thanks for the article it will definitely help when I find a metering lever. If someone could lead me towards one that would be great.

[Matt]

Hopefully someone here will have one for you. I'll check my stuff but I don't know if there is a good one.

[gerkendave]

Thanks Matt

[gerkendave]

Would a wda-31 have the same metering lever?

[Matt]

Should be.

[gerkendave]

OK one on eBay will be watching. Whole carb so hopefully it is ok just needing a rebuild. What are the differences in the model numbers?

[400brian]

I think I would stick with the WRA-31 carb. These seem to work well.

The differences are subtle. The WDA-34 used on the '73 X8s look just like the WRA-31s used on the '74 X8, but the mid-range fuel flow was too rich on the WDA-34. I've been running a WRA-31 on my '74 X8 for 8 years and 6 Vintage Challenges.

As far as I know, the metering lever is the same in all the internal pump Walbros. The ( discontinued ) complete kit used to come with a new one. Be advised: you may have to set your metering lever lower than specs to get it to work right. Several of guys here have made that observation.

[gerkendave]

Thank you for the insight. I'm planning on using my current carb just trying to source the metering lever from another carb and don't really want to spend 80-100 bucks on a carb to do that. The wda on cl is a bidding auction staring at 9.99 so hopefully it goes reasonably cheap.

[gerkendave]

Well the artic cat walbro (wda-31) carb I was bidding on ended today and luckily I got it for 9.99 now just to wait for it to show up and hopefully it will have a good metering lever in it. Will keep everyone updated and thanks again for the assistance.