Walbro HDC carb, Super 2 Check valve screen

[ken8831200]

Just wondering if any one has a trick on getting the tiny retaining ring that holds the check valve screen in place.

I thought I would try but am not having any luck and it might be just better in the long run to see about getting the kit
for the check valve to be sure the little disk is good too.

I dealt with all sorts of snap rings in the 40+ years working on heavy equipment but none as small as this!

I imagine the factory has some special tool, maybe like a tube with a taper inside and a plunger to push the ring into place.

I even watched the Walbro video and they don't show anything there that I noticed and believe some where it says not to change the screen just spray cleaner through it.

And in Leon's video the carb he rebuilt needed a new check valve so he just popped the old one out and used a new one.

[edju1958]

It seems to me that a member here recently just did a check valve replacement & he used something simple to tap the clip into place.He did a tutorial on it if I remember correctly.

[riseandrun]

See if this helps. houseofhomelite.proboards.com/thread/9163/walboro-check-valve-removal-install Let us know how it goes.

[ken8831200]

Well unless I missed something that was showing how to remove the complete valve with the screen and ring already installed.

What I was looking for is how to replace the screen and retaining ring without removing the brass ring and the valve.



Not sure why that picture is so small but it was copied out of the thread that showed how someone replaced the valve. If you look close you could see where the screen and ring were already assembled in the brass ring.

Just noticed that if you click on the picture it will show up full size.

[xl130]

A small hooked pick set or a micro flat head screwdriver is what you need. Very very very careful work your way in from the open slot of the retaining ring. Go real slow and be patient and you can pop it up out of place. Same thing for when you go to put it back in. Real careful.

I pushed too hard when I was trying to remove the ring and ended up ramming the hook straight through the screen and into the check valve.

I’d recommend watching this before doing anything else:

youtu.be/n16qcMctvnw

[ken8831200]

Mar 23, 2020 16:06:38 GMT -5 xl130 said:

A small hooked pick set or a micro flat head screwdriver is what you need. Very very very careful work your way in from the open slot of the retaining ring. Go real slow and be patient and you can pop it up out of place. Same thing for when you go to put it back in. Real careful.

I pushed too hard when I was trying to remove the ring and ended up ramming the hook straight through the screen and into the check valve.

I’d recommend watching this before doing anything else:

youtu.be/n16qcMctvnw

Yes I already viewed that and in it Leon used a preassembled screen and brass ring like in the picture above. I have tried many times to get that little ring in place but have had no luck.
Guess I just need to find the preassembled on ones on E-bay like he suggested. Not sure about how good that little disk of the valve is on a carb that is 37 years old!

[xl130]

If you live in Canada Banta Saw has the brass assembly like in the picture. If you live in the US maybe someone else here can point you in the right direction.

Walboro part number 86-523. Good luck.

[edju1958]

I found them at the best price on RepairClinic.com

[ken8831200]

Mar 23, 2020 19:00:30 GMT -5 xl130 said:

If you live in Canada Banta Saw has the brass assembly like in the picture. If you live in the US maybe someone else here can point you in the right direction.

Walboro part number 86-523. Good luck.

I'm a bit confused as where I have looked it shows a kit number 86-601 for a Walbro HDC-65 Carb which is what mine is marked as being.

In the pictures I see for the 86-523 they seem to be picturing a welch plug along with the check valve, could that be the reason for the different part number?

[xl130]

Ah yes. I apologize! I assumed it as a HDC 44. Definitely use the part number that’s listed by the supplier.

[ken8831200]

Thought I give a bit of an update and see if anyone had some suggestions on where to go from here.

First off I did get the Super 2 running today and after going back to the 1 turn out from closed on both mixture screws and backing out the idle speed screw several turns it will idle pretty good. Just for information the carb was reassembled wit a genuine Walbro K10-HDC repair kit and this is a Walbro HDC-65 carb.

That said I am still having a problem I assume is carb related. 

Saw after having it running it will restart with one or two easy pulls on the starter but despite trying adjusting the high speed screws it will die if you give it throttle too fast. 

If this was an old 1959 Chevy with a 235 Six I would say the accelerator pump was bad!

If you play with the throttle trigger and get the RPMs up a little it then seems to run good at high speed. It's the dead spot when you want to try cutting that will almost always cause it to stall. One easy pull on starter with no throttle and it fires right up. And if you keep the RPMs up it seems to be good.

I probably should have made note of how many turns are on the mixture screws at this point and next time I'm out in the garage I check that as that may tell someone where the problem might be. I do not have the pressure gauge set-up to test the carb but I might be able to rig something up if I can locate a pressure gauge for not too much, don't think the pressure gauges off my compression testers would be sensitive enough!

One thing I did not touch on this saw was the oil pump. I did put a new check valve(duck bill) in the fuel tank and one in the oil tank while replacing fuel and oil lines. Not sure but thinking that if there was a problem in oil pump I would see a lot of smoke like when the duck bill fell off in the oil tank on my other Super 2. And on a quick check of the oil tank after trimming several pine branches both the oil and fuel tanks were pretty low.

[xl130]

Does it stall out in the cut under load or is it bogging when you first hit the throttle with no load and then it will rev up and run good?

It sounds like you’re probably pretty close to having it tuned good. Just a small adjustment on the mixing screws.

If it bogs when hitting the throttle with no load I usually just add a bit more on the low screw. Small adjustment, then hit the throttle and do this over until it transitions to the WOT without bogging.

If it bogs under load possibly you have the high screw a bit to rich?

I usually have my high screw a bit rich because I’m scared to run too lean.

Try that. Maybe the real pros here can give you more directions if this doesn’t get you straightened out. I’d be interested to hear the others. I have this type of problem often after installing carb kit.

[onlyhomelites]

It does sound like fuel starvation on the L side. XL130 is correct that L needle is the one to adjust when you have a hesitation on acceleration. Your analogy of a bad accelerator pump is a good one...the L circuit has 3 different holes in the carb throat so that as the throttle plate opens up, the air flow will draw more and more fuel through the L circuit. It isn't till your at about 1/2 throttle that the H circuit takes over.

Which circuit plate gasket did you install? The K10-HDC comes with two different ones and it can be easy to mix them up. The HDC-65 uses the one that has a "Z" shaped fuel channel.

[ken8831200]

Mar 30, 2020 8:56:45 GMT -5 onlyhomelites said:

It does sound like fuel starvation on the L side. XL130 is correct that L needle is the one to adjust when you have a hesitation on acceleration. Your analogy of a bad accelerator pump is a good one...the L circuit has 3 different holes in the carb throat so that as the throttle plate opens up, the air flow will draw more and more fuel through the L circuit. It isn't till your at about 1/2 throttle that the H circuit takes over.

Which circuit plate gasket did you install? The K10-HDC comes with two different ones and it can be easy to mix them up. The HDC-65 uses the one that has a "Z" shaped fuel channel.

I'll double check to see which gasket is still sitting on the bench but am 90% sure I used the "Z" gasket as I did take the class you posted online about the carb.

Next time I'm out there I will open the L needle a bit more. I was thinking I had that one good as it would start esy and idle good.

Just want to get it running real good before I treat it to a new bar and chain and sprocket. I like this one as it has the lock nut to hold the sprocket on in place of that snap ring that can be a trick to remove and replace!

[xl130]

Here is a video on changing out the screen and retaining ring. Disclaimer: unedited and not the best camera/ smartphone angle but you’ll get the idea I think.

Let me know if this link works. If not sill try another share method.

www.flickr.com/photos/186096937@N03/shares/197K0v

[xl130]

Apr 18, 2020 11:42:04 GMT -5 xl130 said:

Here is a video on changing out the screen and retaining ring. Disclaimer: unedited and not the best camera/ smartphone angle but you’ll get the idea I think.

Let me know if this link works. If not sill try another share method.

www.flickr.com/photos/186096937@N03/shares/197K0v

Ignore that video. It cuts out the part that actually matters.....

Here:

youtu.be/6FsgzO5Y86c

[ken8831200]

Apr 18, 2020 12:05:57 GMT -5 xl130 said:

Ignore that video. It cuts out the part that actually matters.....

Here:

youtu.be/6FsgzO5Y86c

Not sure if my fingers are too big or the cataract surgery was not good enough to let me see tiny bits like I used to, but try as I might I could never get that ring that came in the gasket kit to even start in the brass ring. What I did end up doing is make a new ring out of a spring I had that was a slightly thinner wire and that one I was able to get in place.

Thanks for posting the video, I'm sure it will help someone in the future.

Now if the weather and my ambition will get in sync maybe I can do some fine tuning on this Super 2 and start cutting firewood!

Ken in NY