Husky 268XP dies(seeking the experts)

[Husqvarna1985]

Seeking the experts on this one, I'm pretty good at tinkering with these saws but need some opinions on which direction to go from here. Fixing a co workers old grandfathers saw. 1991 Husky 268XP. Im at the point where the saw will start, idle and run fine, but after 2 or 3 cuts it will start to bog, hang idle(like its running out of gas) and die. Carb adjustments make no difference. Come back the next day and it will start up again like it never happened. Here is what i have done to the saw:
-New piston rings and all new engines gaskets including new crank seals(150 psi comp cold)
-New Tillotson carb(not a chinese), old one had some throttle shaft play.
-New fuel line and filter
-New plug gapped correctly, check coil gap.

I vacuum tested the tank with my handheld vacuum pump, goes from 5 in hg to 3 in 30 seconds, which according to a tech manual test i found floating around on the net is a pass, so the tank vent should not be an issue, and yes i have tried cracking the cap while its in bog mode and doesnt make a change.
My next thought was the crank seals, and yes i have not vacuum/pressure tested the bottom end however i was able to spray some starting fluid around the seals during run time and it did not make a change in RPM.
My other thought is this could be ignition related, but will a failing coil cause a saw to bogg and idle high like it has been doing? i suppose a should try another spark plug to rule it out.
I do have a handheld vacuum pump but dont have any adapters to do a vacuum drop test. i guess i should eventually "tool up" if i'm going to keep working on these things. Either way, I'm trying to avoid the "load the parts cannon" method of repair.

 

[Husqvarna1985]

Heres a pic of it all cleaned up, it was a filthy mess when i got it

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[champion221elite]

Heres a pic of it all cleaned up, it was a filthy mess when i got it

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Nice looking saw. Nothing tech related to add, but I will be following this thread for knowledge.

 

[Cliff R]

Coincidentally I'm going thru the EXACT same thing with my 268XP.

I had troubles with it a few years ago and replaced EVERYTHING with no improvement. Long story but it got crank seals, carb kit, fuel lines, fuel filter, tank vent, intake gaskets, etc. Didn't fix it. At that point I removed the welch plug on the Tillotson carb and blew thing out and it's been fine till a few weeks ago.

Started doing about the same thing yours is doing. Fires right up, cuts fine for a cut or two, but then starts acting lean, idling poorly and stalls out. A little difficult to start at that point but repeats the scenario all over again. I kitted the carb again and removed the welch plug and cleaned that deal out as well, no improvement.

I check the fuel line, tank vent and intake gaskets, all are fine, still does it. I ran out of time and shelved it, must have missed something someplace but it does NOT act like a coil, it acts fuel or air leak related........Cliff

 

[Cliff R]

Coincidentally I'm going thru the EXACT same thing with my 268XP.

I had troubles with it a few years ago and replaced EVERYTHING with no improvement. Long story but it got crank seals, carb kit, fuel lines, fuel filter, tank vent, intake gaskets, etc. Didn't fix it. At that point I removed the welch plug on the Tillotson carb and blew thing out and it's been fine till a few weeks ago.

Started doing about the same thing yours is doing. Fires right up, cuts fine for a cut or two, but then starts acting lean, idling poorly and stalls out. A little difficult to start at that point but repeats the scenario all over again. I kitted the carb again and removed the welch plug and cleaned that deal out as well, no improvement.

I check the fuel line, tank vent and intake gaskets, all are fine, still does it. I ran out of time and shelved it, must have missed something someplace but it does NOT act like a coil, it acts fuel or air leak related........Cliff

 

[Husqvarna1985]

Nice looking saw. Nothing tech related to add, but I will be following this thread for knowledge.

Yes its a shame she is giving me so much trouble. I got some professional grade automotive trim restore that really brings some life back to the plastics. She is definitely a looker!

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[holeycow]

I’m watching this as I am in the preliminaries of going through the same symptoms in my 2152. I thought the second carb cleaning fixed it, but no.

I committed an atrocity and ordered a carb from China. I’m “loading the parts cannon” just this once. If this doesn’t work I’ll wait till I have time and figure it out for real.

I really, really like this 2152. It is such a nice little saw to run. My favourite saw.

I ran most of a tank thru my 1990 262xp a couple of days ago. Other than the nice feel, I wasn’t really that impressed with it when I first got it, or really until a couple of days ago. But finally, after 4 or 5 sharpenings of the chain ( which was all wrong when I got the saw) it is cutting really well and is a pleasure to run. It’s just a little raw, like an old muscle car. Nice. My favourite saw.

The Echo cs590 is tuned and on the bench for the next go..I’ll probably take one of the Jonny 590’s out with it..

Lately it seems that every time I run one of my saws I think “wow, this is my favourite saw”..every one has a unique personality.

That personality only comes fully out with a properly sharp chain.

Bump.

 

[Gord404]

Leaking carb adapter block will cause it not to pump properly through that small hole or tank vent if it has one can be another problem.

 

[rupedoggy]

https://www.ebay.com/itm/Ignition-C...392800?hash=item3b0d8ca9e0:g:BqoAAOSwtNFa~jRt

 

[Husqvarna1985]

Leaking carb adapter block will cause it not to pump properly through that small hole or tank vent if it has one can be another problem.

I inspected it for any issues, it has new intake gaskets and i TRIPLE check to ensure that everything was put together right, no gaskets pinched, etc. But i will check it again with a fine toothed comb if i cant find anything else.
I tested the tank vent with my vacuum pump. Brough it down to 5 in Hg and counted for 30 seconds went to 3. per the test this is a pass. for the heck of it i did the same test on my 61 which is a known runner and it had roughly the same results. I think the tank vent can be ruled out

 

[Husqvarna1985]

https://www.ebay.com/itm/Ignition-C...392800?hash=item3b0d8ca9e0:g:BqoAAOSwtNFa~jRt

This might be my next more...it just seems odd that the saw will race up like its out of gas? would a bad/failing coil cause this?

 

[rupedoggy]

Well maybe next time it dies squirt some fuel mix into the carb. If it runs for a short time then it is fuel related probably. Like you say reving up before it dies would normally mean a fuel issue.

 

[Czed]

Check the fuel line
I know it's new but I've had new one's collapse
While running.
Check for a crack in the intake block
They can be tiny but expand under tension
Simple tough saws i run them all the time.

 

[JohnT34]

Hi there
I have seen the problems you are having on a number of saws on that chassis and I would suggest the following
1. Pull exhaust and inspect piston are there any scoring marks even very fine ones that would indicate an air leak - just cos you changed all the seals doesn’t rule out a leak
2. It sounds suspiciously like an impulse problem by any chance has the cylinder gasket being put in in the incorrect orientation and blocked the impulse hole as this would create the problem you are describing - this would also not show up on a pressure vacuum test
3. Unfortunately pressure vacuum test is a must in this instance or else you are just guessing
4. When you changed PTO seal did you change or reseal the pump o ring as this is a common air leak. Also might be worth checking that the spring hasn’t come off the PTO side seal during refitting of the pump I have seen it happen
5 if it’s a coil replacing it with a good used oem or new oem will resolve - but based on your symptoms if the saw has spark it wouldn’t be my first port of call
6 does the saw behave the same with the new and old carbs as if it does a carb issue would be lower on my list
That’s all I can think of for now with the info at hand

Best of luck
John



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[Cliff R]

I'm sort of out of ideas myself.

I also vacuum tested the tank vent even though it was recently replaced. I even tried moving the metering lever around a little as this sure seems like a carb issue, but it does pretty much the same thing set a tad high or low.

Went on to replace the fuel line even though the one in use tested fine with my vacuum pump.

For the moment I'm stumped.

As a coincidence my Echo SRM-230 string trimmer took a dump last night. It's been pretty much flawless since around 2003. It went WAY lean, then stalled. Would restart and run on choke only. I replaced the carb (had the original as a spare in the box kitted, tested and ready to go). No improvement.

I pulled the large grommet out of the tank, fuel supply line, filter, bypass line and vent line/vent. All looked fine and the fuel line vacuum tested OK. Hum?

Double and triple checked the carb to intake gasket and it's good. Pulled the intake and the intake to cylinder gasket is fine. Just to make myself feel better I replaced the tank grommet, filter and all the lines.

It roared to life and runs fine again. That sort of bummed me out because I spent much longer on the 268XP, found nothing wrong anyplace, replaced some parts and didn't find the issue........Cliff

 

[Husqvarna1985]

I tried a know working spark plug off one of my other saws last night and no change. I think it has to been something fuel/air related.
I wont have time to play with the saw again until after the holiday, but i want to thank everyone for their input so far, alot of get info being put out though this forum!!!
I will certainly follow up if i find anything

 

[Sam R]

To my knowledge not many things work fine cold or unloaded and quit working once loaded or warmed up. Coil comes to mind. I've seen things idle fine but not want to rev up due to a worn pump diaphragm but it's usually when the diaphragm is obviously old and potato-chippey.
Tank vents. But it sounds like you ruled that out. Or an air leak, as others have suggested. Sometimes a minor one means you idle and start up fine but it can't handle any load or high RPMs. Definitely do a crankcase leak test for vacuum & pressure. If you can't rig it up a local shop might do it for you for a small fee or maybe no charge at all.

One thing you can try if you suspect fuel delivery, specifically the carburetor is to take out the H & L screws and blow a little - I always use non flammable brake cleaner - through each needle hole and observe it coming out the venturi. If you've a plug there, that might be your problem & diagnosis; plugged hi speed check. Be sure and conduct this test with safety glasses on and plenty of light because it can sometimes come shooting out of there and it seems to aim for the eyes.

 

[Husqvarna1985]

ISSUE RESOLVED! A couple of you guys mentioned impulse tube which i never really focused on before. Took the carb off and sure enough right where the carb spacer mates with the engine was a big chunk of carbon. Picked it out with piece of wire and a shop vac and then cleaned the hole with a little carb cleaner and a que tip. Put everything back together thing runs like a scalded dog. My co-workers was over joyed when i called him and told him. Im actually very jealous this saw is an animal. Thanks to all the advice given by everyone! This forum is amazing!

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[JohnT34]

I had a feeling it was impulse related
Nice one
Nothing quite like solving a problem


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[holeycow]