Is my Husqvarna 455 Rancher worn out?

[dman535]

My 455 Rancher seems to start ok, has trouble idling and then won't restart when warm.

I followed the Husqvarna manual in diagnosing the ignition module, it will throw a spark over a plug that is gaped at .040.
I put a compression tester on it cold and it came up about 110, read about 90 when warmed up. The tester I have was not specific to 2 cycle motors so I am not sure I got 100% seal on the cylinder.
The saw is 11 years old, tough to gauge if its down on power or not. I just know that its not running right and on our property I need a good running saw. I will verify compression tomorrow. Any other thoughts on what the problem might be?

 

[lostone]

My 455 Rancher seems to start ok, has trouble idling and then won't restart when warm.

I followed the Husqvarna manual in diagnosing the ignition module, it will throw a spark over a plug that is gaped at .040.
I put a compression tester on it cold and it came up about 110, read about 90 when warmed up. The tester I have was not specific to 2 cycle motors so I am not sure I got 100% seal on the cylinder.
The saw is 11 years old, tough to gauge if its down on power or not. I just know that its not running right and on our property I need a good running saw. I will verify compression tomorrow. Any other thoughts on what the problem might be?

Could be several things. Weak compression is one of them, seals leaking is another (as it warms the seals move away from the crank changing your tune). I'm assuming you have the air filter clean and checked/replaced the fuel filter? Carb could need rebuilt. It's hard to diagnose something in a chat room. A compression test and a pressure vac test will tell a lot though.
Fuel tank vent could be another reason for it starting then getting hard to start when warm, run it till it's warm and it starts acting up, turn saw on it's side (fuel cap up) and barely loosen the fuel cap and see if it straightens up. Also when running turn the saw on both sides and listen for the engine to change speed.
Another thing is pull the muffler and look at the piston through the exhaust port. Whats the spark arrestor screen look like, is it getting clogged up.

 

[lostone]

Tests that don't cost anything but time: OK maybe a couple of dollars. and not necessarily in this order.
1. Check spark arrestor screen (possibly clogged with carbon build up) usually more of a bogging/slow throttle response and low power issue but doesn't hurt to check.
2. Pull muffler and check condition of piston/rings and cylinder.
3. Since you have a compression tester, testing compression with one you can trust, Schrader valve must be at end of hose where it enters the cylinder. Test pressure then place a teaspoon of oil in spark plug hole and test again, if it raises more than a few pounds your more than likely looking at a ring job if everything else is in good shape.
4. Running saw until warm and if it starts acting up and loosening the fuel cap helps (tank vent)
5. If saw warms up and you can tilt is on one or both sides and the engine runs differently most likely seals but could be a cracked fuel line sucking in air.
6. If you have never replaced the fuel filter stop by a Husky dealer and get a new one and change it, cheap maintenance, get OEM so you know you have a quality filter it's not worth saving $1 on aftermarket or getting a knock off claiming to be OEM off Fleebay or Amazon.
7. Also if the saw has a fair amount of time on it and you have never changed the spark plug get one from the dealer and change it (to many fakes on Fleebay and Amazon anymore to trust them) could be the plug is breaking down or has carbon streaking down the side of it.
8. Make sure air filter is clean or replaced. Always blow them out from the inside out with light pressure, no need to blast the filter with a lot of pressure to clean it.

Like I said before, it's hard to diagnose in a chat room but there are several things that can cause a run issue.

 

[Jasonrkba]

Those comp numbers are really low. It might be time for a set of rings.

 

[husky455rancher]

I would start with rings too. Probly lose the base gasket while your in there.

 

[Yukon Stihl]

I would start with rings too. Probly lose the base gasket while your in there.

No base gasket it’s a clammy

 

[husky455rancher]

No base gasket it’s a clammy

Oh yeah……

 

[m21bmr]

I enjoy working on saws and try and find saws to refurbish. Over the years I have repaired a few 455s. At least two of them had no real issues other than stuck rings. Both saws measured low on compression and had pistons with no scoring, but the side of the piston near the rings were somewhat brown and the deposits had solidified enough in the ring grooves to keep them compressed. I don't know if it is a real common thing with that particular model, but on the ones I worked on, once I had things cleaned up and the rings moving freely, they both ran great, so I'd definitely recommend checking for stuck rings.

 

[Yukon Stihl]

I picked one up last year with a bad bar stud...
They canot be changed,which sucks otherwise i would have left it.I had a new tank with the filler busted so i was going to use the studs from that tank...nope not happening.
I will try to weld a new end to the stud and see what happens,got a butchered up 346 from him too.

 

[m21bmr]

I picked one up last year with a bad bar stud...
They canot be changed,which sucks otherwise i would have left it.I had a new tank with the filler busted so i was going to use the studs from that tank...nope not happening.
I will try to weld a new end to the stud and see what happens,got a butchered up 346 from him too.

If you are referring to a 455, I think the front bar stud can be tapped back through the oil tank, and the rear it seems like comes out behind the oil tank near the muffler. I don't have experience actually changing the studs, I believe they are replicable.

 

[dman535]

I enjoy working on saws and try and find saws to refurbish. Over the years I have repaired a few 455s. At least two of them had no real issues other than stuck rings. Both saws measured low on compression and had pistons with no scoring, but the side of the piston near the rings were somewhat brown and the deposits had solidified enough in the ring grooves to keep them compressed. I don't know if it is a real common thing with that particular model, but on the ones I worked on, once I had things cleaned up and the rings moving freely, they both ran great, so I'd definitely recommend checking for stuck rings.

What should compression be on these saws ?

 

[dave mclennan]

My 455 Rancher seems to start ok, has trouble idling and then won't restart when warm.

I followed the Husqvarna manual in diagnosing the ignition module, it will throw a spark over a plug that is gaped at .040.
I put a compression tester on it cold and it came up about 110, read about 90 when warmed up. The tester I have was not specific to 2 cycle motors so I am not sure I got 100% seal on the cylinder.
The saw is 11 years old, tough to gauge if its down on power or not. I just know that its not running right and on our property I need a good running saw. I will verify compression tomorrow. Any other thoughts on what the problem might be?

IMO THE 455 IS a ****** saw so many better ones for the same coin, its heavy, and power is ok at best, for the money, i have a few friends with the 455 and they seem to last, i would not spend money to fix it id get a better saw this time,

 

[dman535]

IMO THE 455 IS a ****** saw so many better ones for the same coin, its heavy, and power is ok at best, for the money, i have a few friends with the 455 and they seem to last, i would not spend money to fix it id get a better saw this time,

Thoughts on a replacement, was looking at a Stihl 311. It would at least allow me to use all my existing chains without soen6 a ton, a bit more power as well.

 

[rocketnorton]

stihl's version of what you have
034/6 if ya want stihl

 

[m21bmr]

What should compression be on these saws ?

I don't know the Husqvarna specs for the saw, but in general, you need around 100 psi as a minimum to run. Desirable compression for most chainsaw engines is closer to 150 psi.

As far as whether to spend money fixing your 455, I think it is definitely worth fixing. It isn't the best chainsaw possible, or a power to weight ratio king, but it is a capable saw. If you choose to get another saw, at least repair your 455 to sell, or sell it to someone else as a fixer upper.

 

[wanab]

Back in the day the 455 was a decent saw for the money. It easily outperformed the 290 Farm Boss. Now with the price being $500 compared to $350 years ago there are better options. If my memory is not failing me the compression should be around 150 psi. A new piston and rings is a lot cheaper than a new saw.

 

[magoo]

The 455 Rancher has a compression release. Perhaps, it's leaking.

​

 

[dave mclennan]

Thoughts on a replacement, was looking at a Stihl 311. It would at least allow me to use all my existing chains without soen6 a ton, a bit more power as well.

depends on your budget i love the makita 5600 light fast, cheaper than the stihl 261 which is [IMO The king of firewood saws, if you have years of firewood cutting ahead of you like i did, get a pro 50 to 60cc saw as you grow older you will appreciate the lightness of these saws, and the power is great, makita dealers are few in b. c. but lots of stihl dealers if you go with the 261, good luck ive seen lots of huskys just wear out to fast. enough to see a pattern, but its my opinion which were allowed to express here

 

[Captain Bruce]

My 455 Rancher seems to start ok, has trouble idling and then won't restart when warm.

I followed the Husqvarna manual in diagnosing the ignition module, it will throw a spark over a plug that is gaped at .040.
I put a compression tester on it cold and it came up about 110, read about 90 when warmed up. The tester I have was not specific to 2 cycle motors so I am not sure I got 100% seal on the cylinder.
The saw is 11 years old, tough to gauge if its down on power or not. I just know that its not running right and on our property I need a good running saw. I will verify compression tomorrow. Any other thoughts on what the problem might be?

Saw is worn out. Period. and, your compression gauge doesn't have a brain....its connected to an engine. It doesn't lie.

 

[dman535]

I made a purchase today. Seemed like the Echo CS-590 has gotten some good press. With a leftover Home Depot gift card it knocked the price to half of what the Still MS-311 would have cost. My only complaint is the 70 tooth bar , I will have to get a new bar to take advantage of all my chains from the 455.
I fully intend on cracking the 455 open and seeing what it needs. I do need a reliable saw around the homestead and I hope this Echo will serve me well.