Going through a 346 OE at work..

[RIDE-RED 350r]

So, at work there is an '01 346xp OE. It has been finicky and a bit unreliable and has been replaced by a 550xp.

I asked my boss if I could go through it and do an overhaul.

I got an OE (OEM) cyl kit, new fuel line, fuel filter, tank vent, carb kit, crank bearings, crank seal, updated intake partition and of course the gasket set.

I got it all back together today and it does run, but it isn't tuning in the way it should. It acts just like an 038 Stihl I worked on recently that ended up having a rip in the intake boot. It runs best (but not the way it should) with the high speed jet almost seated and the low speed about 1-3/4 turns out. I should have known better and got the new intake boot and pulse line. Nothing jumped out at me as a problem as I swapped the two into the new partition... Kinda weird, but anyway I have ordered the intake boot and pulse line. I'm thinking that it might not be getting a good seal for the pulse port on the boot where it mates to the carb unless of course I find an obvious issue with the boot.. We have been working our tails off plowing roads all week and I'm running on 9hrs sleep for the last 3 days combined.. Given that, probably not the best day to assemble a saw. But here is where it sits nevertheless.

So I took some pics as I made progress today.

BTW: It looks like I have a couple more saw jobs lining up on the side soon. I plan to invest my earnings in some needed tools for further work like a Mini Mighty Vac, case separator for saws with stuffers, proper flywheel puller and a few other things....

 

[RIDE-RED 350r]

Couple more....

 

[Adirondackstihl]

 

[RIDE-RED 350r]

Last two.

 

[RIDE-RED 350r]

Ya know AdirondackStihl, I didn't check that little fitting as closely as that... Could very well be the problem.

This saw is 15 years old and the intake is original. Are they known to fail there??

As I said in the first post, I should have known better and got the intake and pulse line in the first place, but I didn't want to make the boss think I was buying parts without good reason and running up the cost... I have done every other possible thing that could cause it to run like that.

 

[Adirondackstihl]

Ya know AdirondackStihl, I didn't check that little fitting as closely as that... Could very well be the problem.

This saw is 15 years old and the intake is original. Are they known to fail there??

As I said in the first post, I should have known better and got the intake and pulse line in the first place, but I didn't want to make the boss think I was buying parts without good reason and running up the cost... I have done every other possible thing that could cause it to run like that.

This is the 2nd one I've seen like this.
One on a 350, one on a 346.
I have a spare boot if you need it.
Recommend getting a new impulse hose though. I think they're like $0.70

 

[RIDE-RED 350r]

I appreciate the offer, but I have already ordered a boot and impulse line from GKS.

Unless some other more important job comes up tomorrow, I'll be pulling that boot and checking it over with a fine toothed comb. Which of course means pulling the jug.

 

[Ktoom]

Vac and pressure tester will help diagnose the carb too. Then u can help pin point if the carb is the problem or the intake boot. You can also test the old impulse and fuel lines, as well as testing the fuel tank to see if its venting properly.

Most of the time i just replace all the rubber stuff, but its nice to know where the problem is and or was. Goodluck and have fun!!!

 

[old guy]

I had two oe's that wanted the h needle allmost shut and still wouldn't pull top revs, a carb kit cured em both.

 

[Adirondackstihl]

Which of course means pulling the jug.

Chitty design IMO

 

[Simondo]

Chitty design IMO

Boots are best put on your feet IM humble O.. and taking them off is easier than on a 346

 

[RIDE-RED 350r]

I did do a carb kit too... Forgot to mention that in the first post. Full disassembly and careful cleaning and ensuring nothing was plugged up.

 

[psuiewalsh]

I had an oe with the boot torn there too where it fits into the cylinder. It failed the pressure test though.

 

[RIDE-RED 350r]

OK fellas, I brought the saw home with me to tinker with over this weekend... Here is what transpired...

-I pulled the top end, removed the intake boot from the carb mount and closely inspected for damage. I found none.

- I deleted the base gasket, re-installed the top end along with the original intake boot and tried to run it again, no change.

- As a means of tracking down the problem, I took the Zama carb out of my NE 346xp and swapped it into this OE 346xp to see of this issue is carb related... I left the high and low speed setting untouched from my personal 346 and guess what, it ran PERFECT! Throttle response was better, and you could just tell it was "right"..

-So, the carb is the problem. I took the old hda159 back apart, re-checked everything. Even swapped in the old metering lever just in case ( I now have the Walbro metering lever gauge on the way) pulled the jets, checked the nozzle/check valve as shown on Walbro instructional video (checked out good) and still this saw runs like crap on the original Walbro. I had this carb on and off, disassembled and reassembled 5 times to no avail. Tried compressed air in the high and low speed circuits... I am out of thigns to try, save one... Stripping it down and soaking in Napa carb soak solution.. Not spray carb cleaner, this comes in a one gallon can like a paint can.

All I can think is that there is a piece of debris or fouling in the high speed circuit in the carb body where I can't get to it and compressed air won't clear out.

If the soak doesn't cure it, I guess I'm going to get a new Zama c3el18 for it. When I swapped the Zama from my NE, I just capped the primer port on the carb. Worked perfect. I don't see the Walbro hda159 available for sale anywhere I have looked so far. And that's OK, the Zama is cheaper and runs fine on my NE.

So all of that said, does anyone have any suggestions for me to try that I may have missed???

Gonna be ordering a Zama in a couple days if I can't make the Walbro work...

 

[Simondo]

OK fellas, I brought the saw home with me to tinker with over this weekend... Here is what transpired...

-I pulled the top end, removed the intake boot from the carb mount and closely inspected for damage. I found none.

- I deleted the base gasket, re-installed the top end along with the original intake boot and tried to run it again, no change.

- As a means of tracking down the problem, I took the Zama carb out of my NE 346xp and swapped it into this OE 346xp to see of this issue is carb related... I left the high and low speed setting untouched from my personal 346 and guess what, it ran PERFECT! Throttle response was better, and you could just tell it was "right"..

-So, the carb is the problem. I took the old hda159 back apart, re-checked everything. Even swapped in the old metering lever just in case ( I now have the Walbro metering lever gauge on the way) pulled the jets, checked the nozzle/check valve as shown on Walbro instructional video (checked out good) and still this saw runs like crap on the original Walbro. I had this carb on and off, disassembled and reassembled 5 times to no avail. Tried compressed air in the high and low speed circuits... I am out of thigns to try, save one... Soaking in Napa carb soak solution.. Not spray carb cleaner, this comes in a one gallon can like a paint can.

All I can think is that there is a piece of debris or fouling in the high speed circuit in the carb body where I can't get to it and compressed air won't clear out.

If the soak doesn't cure it, I guess I'm going to get a new Zama c3el18 for it. When I swapped the Zama from my NE, I just capped the primer port on the carb. Worked perfect. I don't see the Walbro hda159 available for sale anywhere I have looked so far. And that's OK, the Zama is cheaper and runs fine on my NE.

So all of that said, does anyone have any suggestions for me to try that I may have missed???

Gonna be ordering a Zama in a couple days if I can't make the Walbro work...

Could you take some pic's of the carb to confirm something for me…the end view from the boot and the filter end .

 

[RIDE-RED 350r]

I'd be happy too, but I'll have to get it tomorrow. Saw is back together and put away and I'm done for the day. I'll pull the carb back off and get a pic tomorrow morning.

 

[Simondo]

I'd be happy too, but I'll have to get it tomorrow. Saw is back together and put away and I'm done for the day. I'll pull the carb back off and get a pic tomorrow morning.

I maybe barking up the wrong tree !! if you are going to pull the carb again anyhow to maybe do a swap permanently then its no aggro for you.

 

[RIDE-RED 350r]

I would if I had the new Zama on hand right now.. I have a feeling it's going to come to that...

And no worries about it being a pain to pull the carb again... I'm getting REALLY proficient at it...I'm talking under 3 minutes! Lol!! I'll pull the carb and get pics tomorrow and post em up. Saw is at home and I'm visiting at my brother's house right now.

But the other component is that I'm mad at this carb because it's beating me. Ha-ha

 

[Simondo]

I would if I had the new Zama on hand right now.. I have a feeling it's going to come to that...

And no worries about it being a pain to pull the carb again... I'm getting REALLY proficient at it...I'm talking under 3 minutes! Lol!! I'll pull the carb and get pics tomorrow and post em up. Saw is at home and I'm visiting at my brother's house right now.

But the other component is that I'm mad at this carb because it's beating me. Ha-ha

Been there on a old edition 346 myself …drove me Nuts ! HDA 182a on mine and it was the fault in the end. Accelerator pump on the carb put all the rest out…I THINK ? the HDA 159 has the accelerator pump to but i could be off track. It was a issue I've been aware of Since my saw nightmare

 

[RIDE-RED 350r]

Is the accelerator pump serviceable??

I don't recall seeing anything resembling an accelerator pump in this carb...but it could very well be that it's there and I just didn't recognize it as one... These little carbs are quite different than the Keihin PWK's that I'm used to working with on my 250R's.