Husq 266XP drive me to drink. Tequila's good, but...

[Rick Stephens]

Have a friend's 266XP that is getting my goat. When I got it, it wouldn't run. Pull on the starter a couple times and the saw would be almost instantly flooded. Owner of the saw runs his own machine shop and logs his own place. He knows much, but never got interested in tearing down saws past normal maintenance. Silly me, I volunteered to help him out.

Checked the obvious stuff first:

*went through the carb again even though owner had just done it. Everything looked right.

*pulled the muff and inspected it and the cylinder - looks fine for an older well used saw.

*compression check over 150

*good spark as long as rotation speed is reasonably high. Replaced wires from coil to mag since they were cracked.

*Pressure and vac test was crap. So started in on that and ended up replacing crank seals, seal mount o-ring on fly side leaked like a sieve as did both gaskets on intake. He had a gasket on the carb end that didn't cover the pulse port. And the cylinder end leaked pulse into the manifold screw hole which then leaked at the carb end. Got it all sealed up with a little 1184 and new pretty much everything in gaskets and it passes pressure and vac now.

After all that, saw does the same thing and floods after a few pulls. So I purchase a fleabay carb. Same thing with it. Pull a few times and the pull rope gets stiffer and stiffer. Pull the plug, all wet. Pulled the carb a half dozen times and changed needle valve lever height. Finally got it where it doesn't flood. Can start this saw with a teeny puff of ether, and then it runs and idles like a champ. But I can pull my arm off trying to start it with just normal choke action - never so much as a snort.

Ideas? I appreciate the help muchly.

Rick

 

[nighthunter]

What's the spark like

 

[Rick Stephens]

What's the spark like

Not very impressive. I regret not owning a spark gap tester at the moment. May have to get one.

 

[Old2stroke]

Does your choke lever automatically set the throttle partially open? Many saws will not start with the throttle closed when they are cold. Does it start easily when hot?

 

[grizz55chev]

Not very impressive. I regret not owning a spark gap tester at the moment. May have to get one.

Spark looks fine, you’ve cover all the bases, maybe take another look at the choke, making sure you’re getting a good seal with the butterfly. Keep us posted.

 

[Rick Stephens]

Does your choke lever automatically set the throttle partially open? Many saws will not start with the throttle closed when they are cold. Does it start easily when hot?

The choke has no connection to throttle. I frequently try to start it with one hand on the throttle to give it full open, with and without choke. I just tried it again, and there was not a pop or a stutter to be heard, by the time I stopped the spark plug was wet.

Spark looks fine, you’ve cover all the bases, maybe take another look at the choke, making sure you’re getting a good seal with the butterfly. Keep us posted.

Two different carburetors. I can pull my brains out. I try it out without choke and the plug is dry after 10-12 pulls. Try it with choke and the plug is wet after 10-12 pulls. I'm starting to talk to myself as its making me look like an idjit.

 

[grizz55chev]

Not all of my saws start the same, sometimes they need a lot of choke, sometimes not. That being said, a flooded saw will cause you to pull till yer breathing hard! Maybe after 3 or 4 pulls, take the choke off and hold the throttle wide open and pull till she pops, that’s how I start the ones that flood easily, they usually start fine after they’re warm.

 

[Rick Stephens]

Not all of my saws start the same, sometimes they need a lot of chock, sometimes not. That being said, a flooded saw will cause you to pull till yer breathing hard! Maybe after 3 or 4 pulls, take the choke off and hold the throttle wide open and pull till she pops, that’s how I start the ones that flood easily, they usually start fine after their warm.

I wish it was that simple. When I use an aide, such as ether, and get it running, it may do pretty good for a bit. But just trying to adjust the carb a little will always result in it dying. I have let it sit and idle to warm up, then revved it a bit and shut down. If I start right back up, all is fine. But if I walk away, it is impossible to start without ether after 5 minutes sitting. Generally, I can't keep it running all that long. Only a couple times has it run for longer than a few minutes. Sounds great at high idle. Is unpredictable at idle. Once it dies, it is dead.

I'm thinking I may go back to the original Tillotson carb. A PITA in that I had to take the throttle shaft out of it and put in the AM carb to match up linkage. I'll get er done and see what I can see. Stick with basics. Husqvarna design on this particular saw is annoying without a high idle position after choke.

 

[grizz55chev]

Damn, I hate when they have gremlins like that! You probably already know that ether is bad for these engines, I use a squirt can of mix gas.

 

[SteveSr]

I wish it was that simple. When I use an aide, such as ether, and get it running, it may do pretty good for a bit. But just trying to adjust the carb a little will always result in it dying. I have let it sit and idle to warm up, then revved it a bit and shut down. If I start right back up, all is fine. But if I walk away, it is impossible to start without ether after 5 minutes sitting. Generally, I can't keep it running all that long. Only a couple times has it run for longer than a few minutes. Sounds great at high idle. Is unpredictable at idle. Once it dies, it is dead.

I'm thinking I may go back to the original Tillotson carb. A PITA in that I had to take the throttle shaft out of it and put in the AM carb to match up linkage. I'll get er done and see what I can see. Stick with basics. Husqvarna design on this particular saw is annoying without a high idle position after choke.

Stupid question... do you have the metering diaphragm and gasket assembled in the correct order? On the pump side the gasket goes ON TOP of the pump diaphragm. On the metering side the gasket goes UNDER the diaphragm. If this is reversed it'll be way too rich and likely to flood.

 

[Rick Stephens]

Stupid question... do you have the metering diaphragm and gasket assembled in the correct order? On the pump side the gasket goes ON TOP of the pump diaphragm. On the metering side the gasket goes UNDER the diaphragm. If this is reversed it'll be way too rich and likely to flood.

Yup. Good question. But I looked carefully and double checked against the manual just to be sure. I had been bending the lever to get a more neutral needle valve as it poured fuel in at first, it was disassembled numerous times..

 

[Rick Stephens]

Damn, I hate when they have gremlins like that! You probably already know that ether is bad for these engines, I use a squirt can of mix gas.

A last resort that surprised me it worked. Done it twice now, little puff and the saw starts. Absolutely nada without it though. I think one more carb swap is in my future.

 

[grizz55chev]

I had a Husky 2100 that had me stumped one time, turned out the plastic fuel inlet-elbow was cracked causing an air leak, look closely at your fuel intake from the filter all the way to the carb, doesn’t take much,and don’t forget the tiny fuel screen in the carb itself.

 

[Rick Stephens]

I had a Husky 2100 that had me stumped one time, turned out the plastic fuel inlet-elbow was cracked causing an air leak, look closely at your fuel intake from the filter all the way to the carb, doesn’t take much,and don’t forget the tiny fuel screen in the carb itself.

Customer replaced it.... so natch, I ignored that. I will do a pressure test on it tomorrow. Thanks!

 

[SteveSr]

Customer replaced it.... so natch, I ignored that. I will do a pressure test on it tomorrow. Thanks!

I have seen bad (cracked) plastic fuel intake elbows several times before, mostly on Walbro carbs. Remove the fuel pickup in the tank and do the pressure test from there. Should hold minimum of 7-8 PSI indefinitely. There should also be metering lever height adjustment instructions on the carb manufacturer's web site.

 

[Old2stroke]

Are you sure about the choke lever having no effect on the throttle? Usually, if there is one lever, when the choke is placed "on" it sets a detent that holds the throttle partially open until released by squeezing the trigger. This is also the way of setting a high idle, you just put the choke on and then take it right off, the throttle will remain set partially open until released by the trigger. I haven't seen a saw other than small top handle ones that don't have some method of advancing the throttle for starting. In earlier days nearly all saws had a button on the handle that you could push in to hold the throttle open, this method was simple and easily understood so of course it had to go.

 

[cus_deluxe]

Did u do a carb kit?

 

[cus_deluxe]

Just cuz it was a new carb, doesnt mean that one was good either...

 

[Czed]

https://www.amazon.com/gp/aw/d/B012HFQAHW?psc=1&ref=yo_pop_mb_pd_title
Oem tillotson hs260a
I had trouble with a new am on my 266
This cured it
40.00

 

[Cliff R]

I had similar issues with my 268XPS when I first got it.

I did the regular things most well used saws need, carb kit, fuel line, fuel filter, tank vent, intake gaskets and no improvement whatsoever. Compression as fine and actually so high it really needs a compression release.

Did crank seals next, no better.

I went back to the carb and turns out there was some crap floating around in it. Got it all cleaned up and it's been flawless since.......Cliff