# Husqvarna 55 Rancher will not idle. But it runs at speed OK.



## steven1955 (Sep 18, 2010)

Hi folks.

I'm trying to fix my neighbor's Rancher 55, but so far no joy. Once warm it dies rather than idle, but if you get it started it will run at speed just fine. I'm worried that this may not be the easy fix I thought it would be. I'm not willing to overhaul his saw past the fuel system or ignition adjustments, if there are any. We're not _that_ friendly.

My neighbor's gas equipment seems to frequently have issues. No one told him about the evil of 10% ethanol until I did this past spring. But he still uses old gas, and his gas cans aren't sealed.

His saw:
Model: Husqvarna 55 Rancher
Code on tag top line: 967 05 29.00
Code on tag bottom line: 02 2301618
Carb manufacturer: Zama
Carb marking on one side: C1Q
Carb marking on other side: EL7 238

What I've done:
1. Inspected the cylinder through the exhaust port. A little black oily residue, but no scratches, and you can still see the cylinder's hone marks.
2. Inspected the cylinder through the intake port. Clean, piston looks nice, and cylinder still shows the original hone marks.
3. Spark plug is clean with no rounding or wear of the electrodes.
4. Compression is 130 psi regardless of the number of pulls you give the rope. A local dealer says 130 is good for a Rancher, but here I've read 150 to 160 is more normal.
5. Replaced the diaphragms in the carb. The old ones were OK, but not like new.
6. Inspected the gas hose. It is not soft, and I can see no cracks.
7. Cleaned the air filter. (It was caked with oily dust and needed solvent to clean.)
8. Inspected the exhaust port (cleaning not required) and cleaned the muffler and screen (which were not at all dirty or carboned up).
9. Tested the saw with fresh 93 octane fuel with Stihl's synthetic oil. (No change in behaviour.)

Here's what I haven't done:
1. Removed the jets to allow a more thorough cleaning. I haven't yet cut off the EPA mandated stops on the jets to allow their removal.
2. Replaced the fuel line and fuel filter, just to be on the safe side.

Questions:
1. Where do you think I should go from here?
2. Where is the fuel tank vent? I think I'm staring right at it, but don't seen one. I'd like to clean it to be sure.
3. Are there any adjustments to be made to the ignition? Like clearance between the flywheel and coil?

Thanks in advance for any guidance you folks can give me.


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## HiOctane (Sep 18, 2010)

Be sure the small rubber on the impluse between white plastic and cyl is not cut.And look at the rubber intake too if well installed or not cut.If ok on both ,i would have a pressure test done.


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## L.R. (Sep 18, 2010)

steven1955 said:


> Hi folks.
> 
> 
> What I've done:
> ...



I think you should bubble test the fuel line before replacing, hairline cracks can be hard to spot. Did you vacuum test the carb? Any shop manual should tell you how, or check youtube.

It sounds like a low speed circuit problem. Did you clean the carb with compressed air? Check the impulse line?

Suggestions for "will not idle from a shop manual:

Low speed needle
Plugged tank vent
Plugged tank filter
Restricted fuel line
Dirt in fuel passage
Loose, damaged fuel line
Defective manifold gasket
Loose carb mounting screws
Throttle shaft too tight
Bent throttle linkage
Defective throttle spring
Bent throttle stop lever

This is for Jonsered 20-series and 6-series. 21-series manual adds:

Adjust L-screw
Leaking air intake hose
Throttle valve pivot stiff
Faulty diffuser jet

Husqvarna 346XP, 359, 372, 350, 353 362XP, 365, 371XP shop manuals add nothing significant to troubleshooting list.

Some Walbro carbs may have mysterious idling issues, but i see youhave the Zama. I'd say fuel delivery is your safest bet?

The clearance between coil and flywheel myst be correctly set. This should be somwhere around 0,3mm or 0.012"? Please correct me on this, I don't have the 55 manual, but the setting is the same for several Husqvarna and Jonsered models I have manuals for.

Good luck!

LR


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## Cliff R (Sep 18, 2010)

A new fuel line and filter should be part of the carburetor build. No need to pull any debris into the freshly cleaned out carburetor, and the fuel lines have a bad habit of developing very small leaks, often right where they pass thru the tank.

I made a SCREAMIN deal on a really nice 55 on Ebay that the owner gave up on after doing just about everything to it, including a new coil. The fuel line was cracked where it goes thru the tank, no other problems with the saw anyplace.

About the only sore spot on a 55 is plastic air filter housing. The screws are easily stripped out in them, and the rubber seal for the impulse is easily dis-lodged when working on the intake side.

130psi compression is acceptable, but all mine are at 150psi or slightly higher.....Cliff


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## Winn R (Sep 18, 2010)

Cliff R said:


> About the only sore spot on a 55 is plastic air filter housing. The screws are easily stripped out in them, Cliff



This is what I'd check first. Install metal nuts in the plastic so the carb can be attached tightly.


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## steven1955 (Sep 18, 2010)

OK, so I took the the tank off to make it easier to clean and inspect the fuel line. Now that it's easy I'll probably just replace the fuel line and filter.

I still haven't found the fuel tank vent. I'm sure I'm staring right at it, but .... Well, can someone tell me where to find the vent. Or does the tank just vent at the grommet where the fuel line enters the tank?

I've been very careful dealing with the plastic air filter housing. The screws aren't stripped. If I damage the housing or find that I can't tighten the carb properly I'll do the metal nut in the plastic repair.

Can I download a shop manual for this saw somewhere? I haven't found it anywhere. (I did find a shop manual for another neighbors Husky 350, but I ended up not needing it. All that saw needed was fresh gas.)

Is the impulse tube the plastic extension to the air filter housing that kind of plugs into a hole in the cylinder just below the intake port. If so, the impulse tube is good, and so is the rubber seal at the cylinder. The rubber tube for the intake port is still soft and pliable and has no cracks.

Would you recommend that I remove the plastic EPA mandated jet adjustment limiting thing? I think I have to if I want to remove the jets to thoroughly clean the carb.


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## Cliff R (Sep 18, 2010)

I don't remove the limiter caps, just snip off the protrusions so they can turn freely in both directions is good enough. I do this in seconds with small pair of wire cutters. Leaving the limiter caps in place makes it really easy to get a good fitting flat tip screwdriver on them when the saw is running for easy adjustments.....Cliff


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## GlenM (Sep 19, 2010)

The fuel tank vent will be a duckbill valve in the fuel cap.


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## CGC4200 (Sep 19, 2010)

*Husqvarna 55 fuel tank vent*

The 55 IPL I have shows a blind side view of a vent going into
opposite side of tank from filler cap, next time I have the clutch
cover off on mine, I am going to look there on the 55.

The PP260 does have a duckbill in the cap.


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## steven1955 (Sep 19, 2010)

Update....

Cut the mixture screw limiter cap extensions off, but left the limiter caps on, just like *Cliff R* suggested. And then I was able to fully disassemble and clean the carb. Thing is, it didn't need it. The carb was spotless. Now it's back together, clean and shiny, with new rubber parts.

Both the HI (red cap) and LO (white cap) were set at 7/8 turns out. I'm sure my neighbor didn't mess with these, and I'm sure he never had it serviced or adjusted. Seems to me that this is lean. Most posts here say these typically are set to 1 to 1-1/8 turns out after the saw is broken in and adjusted properly.

_Question: Is the consensus to set these both a 1 turn out for their initial setting?_

Removed both the induction pipe and the impulse pipe as long as everything was apart. The induction pipe was perfect. The impulse pipe was brown colored at one end. So I will replace it to be safe. (If the saw were running nicely I wouldn't replace it. It just wasn't that bad.)

I found the tank vent, and it's not in the fuel cap. It's a long skinny black plastic thing that is pushed into a hole on the side of the tank opposite the filler. The hole looks like a hole for a screw, so until today I never looked in the hole. The vent is made of two parts per an on line exploded parts drawing, and one part in the drawing not quite big enough to see looks like it could be a duckbill valve. This saw is missing it's tank vent duckbill valve.

So tomorrow off to the Husky dealer for:
1. Some fuel line
2. A fuel filter
3. An impulse pipe
4. A tank vent duckbill valve


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## CGC4200 (Sep 19, 2010)

*fuel tank vent*

Where does it come out?
I looked earlier and came up with 501873101 for the vent tube & 503600401
for the filter plug. I have a 95 made 55, that is why I am interested.
I suspect under the back part of clutch cover.


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## L.R. (Sep 19, 2010)

steven1955 said:


> Update....
> 
> Both the HI (red cap) and LO (white cap) were set at 7/8 turns out. I'm sure my neighbor didn't mess with these, and I'm sure he never had it serviced or adjusted. Seems to me that this is lean. Most posts here say these typically are set to 1 to 1-1/8 turns out after the saw is broken in and adjusted properly.
> 
> ...



Jonsered 2171 manual says between 1 and 1-1/4 turn out for both H and L, this is basic setting for run-in after assembly/reassembly. Different manual says 1 turn for both. Husky 350 etc. manual also says 1 turn. Iy seems the carb is set a bit lean, yes. I'd go with at least one turn out.

Let's hope the tank vent did it!

LR


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## HiOctane (Sep 19, 2010)

steven1955 said:


> Update....
> I found the tank vent, and it's not in the fuel cap. It's a long skinny black plastic thing that is pushed into a hole on the side of the tank opposite the filler. The hole looks like a hole for a screw, so until today I never looked in the hole. The vent is made of two parts per an on line exploded parts drawing, and one part in the drawing not quite big enough to see looks like it could be a duckbill valve. This saw is missing it's tank vent duckbill valve.
> 
> So tomorrow off to the Husky dealer for:
> ...


 
The air vent has two small round white plastic,bottom one being smaller.Use a metal screw to pull them off.I dont think your problem is there,most likely an air leak instead.


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## steven1955 (Sep 19, 2010)

I'm sure the missing gas tank air vent part is not the problem. With the missing vent part(s) the tank was vented. I just want to make the vent is complete as well as properly functioning now that everything is apart.

I'm leaning toward air leak, although nothing I've inspected looks bad enough to leak air.

_Could the jets being set lean cause this "not running at idle" problem?_


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## mountainlake (Sep 19, 2010)

Cliff R said:


> A new fuel line and filter should be part of the carburetor build. No need to pull any debris into the freshly cleaned out carburetor, and the fuel lines have a bad habit of developing very small leaks, often right where they pass thru the tank.
> 
> I made a SCREAMIN deal on a really nice 55 on Ebay that the owner gave up on after doing just about everything to it, including a new coil. The fuel line was cracked where it goes thru the tank, no other problems with the saw anyplace.
> 
> ...



You found out those screws strip out easy too, a piss poor design for a major manufactor, I'm sure they saved a least 50 cent per saw by not putting a metal nut in that plastic piece. I melted a metal nut into the back side of that plastic piece, now I can tighten it properly. Steve


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## steven1955 (Sep 22, 2010)

Update....

Got the last part this morning. The impulse pipe wasn't in stock, hence the delay. So back together the saw goes.

1. Cleaned the carb and reassembled with new diaphragms. None of the internal ports were clogged or dirty. HI and LO jets were removed for a thorough cleaning
2. New impulse pipe.
3. Intake pipe was carefully inspected and found to be soft, pliable, and crack free.
4. New fuel filter and fuel line.
5. As mentioned earlier, the muffler and screen are clean, and the spark plug is good.
6. The screw holes in the plastic carb mount were not stripped. The carb was nice and tight.

Compression before running the saw today was 130 with a cold engine, lower than I would like, but some folks said it was marginally OK.

I should note that I had no tach, so I was using the "no tach" instructions at chainsawr.com

So I tried to get the saw to warm up with the HI and LO both set at 1 turn out. It turns out that I had to increase the idle speed a bit AND increase the LO to 1-1/4 turns out, and then the saw idled as nice as you could want when the saw was cold.

After warming up I tried to reduce the LO a bit, but the saw wouldn't run at 1, ran poorly at 1-1/8, so I ended up leaving the LO at 1-1/4. 

At speed the sweet spot for the HI was about 1-1/8 turns out. I don't claim to be an expert in 2 stroke motors or their tuning, but I did make sure I didn't set the HI for max RPMs. I for sure didn't want to run lean on purpose.

So now, in my back yard, the saw runs great. So I take it into the woods to find a nice fallen tree to test the saw on. In the woods the saw runs great.... Before I make a cut that is.

I find an 18 inch fallen tree that's set up nicely for me to cut on. I make one complete cut of this tree, and the saw is running great for this one cut. Once the cut is finished and I let off the throttle the saw dies.

So as I go to try and restart it I notice that it takes noticeably more effort to pull the saw through than before I made this cut. And the saw won't start. I try adjusting the LO both up and down, but no joy. The only way the saw would start was by holding the throttle open. And when the saw did start, I could not make it idle.

So I take it home, give it about 30 minutes to cool, and checked the compression with the engine still somewhat warm. Compression is now 110 psi.

So what do I do now? I could re check the compression with the saw cold, but I'm not sure what that will tell me.

At this point I'm leaning toward bad piston, rings, and/or cylinder. 

If there's something else non invasive to check/replace/fix I'll do it. But I'm about done with the free labor for my neighbor.

Your turn. What do you folks think?


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## outdoortype (Sep 22, 2010)

*Air leak*

The saw gets hot and maybe the seals expand and create an air leak. I've heard of coils failing when they get hot but I think they quit running altogether. You could use an ohm meter to check the coil because it's fairly easy. I've also heard of spraying something around the seals while the saw's running while listening for a change in idle speed. I just can't remember if it was carb cleaner?


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## L.R. (Sep 23, 2010)

outdoortype said:


> The saw gets hot and maybe the seals expand and create an air leak. I've heard of coils failing when they get hot but I think they quit running altogether. You could use an ohm meter to check the coil because it's fairly easy. I've also heard of spraying something around the seals while the saw's running while listening for a change in idle speed. I just can't remember if it was carb cleaner?



Carb cleaner, ether, starter gas, I think I've heard all three and more, but couldn't say which one would be best. Starter gas is a no-no for starting two-strokes, since it strips the oil from the cylinder and may cause failure, but for this simple test it might be OK?

Trouble shooting for "Engine stops when closing throttle" (rather than "will not idle") lists H and L screws, defective pump diaphragm, metering system set too high, and "binding". This last one I'm unfamiliar with, but it has to do with the fuel metering system.

Other related issues listed in the workshop manual are Leaking crankcase and faulty diffuser jets.

For "L needle needs constant adjustment" manual says to check Fuel line blocked, Needle valve set too high, Needle valve assembly sticking, Leak in metering system (air or fuel), Leaking control diaphragm/ cover plate, Faulty diffuser jets, Crankcase leaking.

For "Uneven idling", add Fuel filter blocked, Leaking air intake hose (rubber), Loose carburettor mounting bolts ,Worn throttle valve pivot, Loose throttle valve screw, Worn throttle valve.

Would a leaking crankcase lower compression? Seems unlikely. Rings not sealing properly for some strange reason?

What a thriller!!!

LR

Edit:

These suggestions are not from the 55 manual, but rather from other Husqvarna/Jonsered manuals. They seem to differ very little.


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## vintagestuff (Sep 23, 2010)

Pull the muffler again and check for scoring.


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## Timberton (Sep 23, 2010)

*Top-End*

I bought a used a Husky 51 and a used Husky 55 that both had the same problem as you described: difficult to make idle, difficult to restart when hot. They both needed top-end work. Upon disassembly, I found that neither was terrible, but both showed signs of piston scuffing/scoring. It doesn't take very much scoring to affect the performance of these saws; and it doesn't take much extra heat, bad gas or shortage of oil to cause the scoring! It can happen in seconds! I was able to get by with just a new piston & rings in the 51; but the 55 needed a new piston, rings, & new cylinder. Crank shaft bearings and connecting rod bearings were fine in both saws. I found top-end replacement on these saws to be a very easy little job, heck I'd say easier than all of the work that you've already done. The only issue is cost of parts. Bailey's and Chainsawr both sell new OEM and new aftermarket top-end kits for the Husky 55. I couldn't justify the cost of OEM parts, so I went the aftermarket route. Upon startup, I set both the high speed and low speed adjustment screws at halfway between the limitors. This was good enough to start the saws. I tune my saws by ear, just as Chainsawr describes on his website. Once saws were warmed up, I had them tuned within 5 minutes. Both saws now running great. No issues. I hope that this helps with your problem.


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## steven1955 (Sep 23, 2010)

*My neighbor just gave me his Rancher.* This was after telling him I'd done all the cheap and easy things and failed, and that I couldn't justify more of my free (to him) time. It didn't help when I mentioned that a cylinder/piston kit from Bailey's was $100. (It didn't hurt that I fixed his Craftsman tractor and Stihl trimmer at no charge. By the way, all victims of bad gas.)

He's not hurting as one of our other neighbors gave him a nice Stihl 250-C (or MS250-C) chain saw and a Stihl hand held blower.

The good is that he's finally listening and understanding the evils of bad gas, and how to feed his equipment good gas.

I'm going to take a temporary hiatus from this thread while I finish the re-engining and POR15'ing of my 1970 Ariens snow blower.

But I'll probably be back. I think the Rancher is also a victim of bad gas, and I may get away with just a piston or p/c kit. But I'll need your help and advise when I get back into the saw unless it's obviously unrepairable.


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## HiOctane (Sep 23, 2010)

Now,its time to check piston condition,probably seized at exhaust side.




steven1955 said:


> Update....
> 
> I find an 18 inch fallen tree that's set up nicely for me to cut on. I make one complete cut of this tree, and the saw is running great for this one cut. Once the cut is finished and I let off the throttle the saw dies.
> 
> ...


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## rcowboy (Sep 23, 2010)

steve1955,

Check your PM's for a message on the manual. I think they are on huskys site, if not check my e-mail in your PM and i'll e-mail it back to you in PDF.


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## L.R. (Sep 25, 2010)

steven1955 said:


> *
> 
> But I'll probably be back. I think the Rancher is also a victim of bad gas, and I may get away with just a piston or p/c kit. But I'll need your help and advise when I get back into the saw unless it's obviously unrepairable.*


*

Let's hope you do! My dealer had about a dozen 55s waiting for new P/Cs, all seized. I'm wondering were they all straight gassed, or is it pretty easy to lean out these saws for some reason? I cannot believe the saw is unrepairable!*


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## sefh3 (Sep 25, 2010)

I was reading somewhere that many models of saws come lean right from the factory to pass EPA inspections. I think you or that saw became a vitim of that. 130 psi is low. After running it and it warms up the compression should increase not decrease. Pull the muffler off and take a peek at the piston. I'm betting it's scored and was before you messed with it.


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## outdoortype (Sep 25, 2010)

If I posted a pic of the scoring on my 51 no one would believe that it ran. If you held starter rope, it would drop almost instantly. But it started, idled and even cut fairly well. Perform a leak test on both the carb itself and then everything from the bulkhead/flange forward.

All saws are set lean to pass EPA standards. But for some reason, I've seen tons of burnt up 51/55's on Ebay.


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## Peter White (Jan 6, 2015)

Steven, did you ever figure out the issues with your Rancher? I am undergoing similar troubleshooting now. My piston and cylinder look to be in great shape


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## dynodave (Jan 7, 2015)

Peter White said:


> Steven, did you ever figure out the issues with your Rancher? I am undergoing similar troubleshooting now. My piston and cylinder look to be in great shape



I know this is an old thread but it made me feel like telling my recent experience with my friends 55 rancher date 3-48.
His 261 I think got burned by a bad gasket on the intake manifold/cylinder joint. broken and leaving a gap...Now in the same batch of broken saws is his 55. Well on the cylinder base to crankcase joint, the gasket is sucked in and has a little hole and is also what cooked this P&C. The piston is very dead meat but I think the cylinder can be saved. It seams that both of these saws ran enough to cut wood for a while, but suffered badly from the leaks.
In both cases a pressure test would have found the problem. On the 261 just prepping for the test would have shown the problem.
see here:
http://www.arboristsite.com/community/gallery/photos/261-epa.2387/


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