Chainsaw Repair

Husqvarna - Stihl - Poulan - Jonsered - Dolmar chainsaws and more => Husqvarna => Topic started by: ub54 on April 26, 2014, 01:35:26 pm

Title: husqvarna 455 rancher
Post by: ub54 on April 26, 2014, 01:35:26 pm
I have a 455 that I would say is sucking air somewhere. Heres the deal. This saw never has run great and a guy wants to buy it, anyway it fires up and as soon as you hit the throttle it bogs down and will die . I put a kit in the carb, does same thing. But, when the choke is pulled out it runs great and idles like it should. The carb is a walbro and it has the two intake tubes on top with the choke below with a throat of its own. I hoped the intake wasn't leaking and everything is tight,but I havenever seen a saw run so good with the choke pulled out . Also I really don't understand why rhere is actually two separate throats on the intake. Where is this thing sucking air ? Its got me baffled. HELP!
Title: Re: husqvarna 455 rancher
Post by: KilliansRedLeo on April 26, 2014, 01:48:32 pm
Is it a 455 Rancher II? Post the serial number.
Title: Re: husqvarna 455 rancher
Post by: brokenbudget on April 26, 2014, 03:36:22 pm
is it tuned properly? or are you only turning the jets as far as the limiters will let you?
Title: Re: husqvarna 455 rancher
Post by: ub54 on April 26, 2014, 05:32:34 pm
I'll have to get the ser#. But ,no I started at one turn out on both high and low that's what I always do . I did turn the high out about a quarter turn twice butby then it should have been running super rich . Believe me , I know my chainsaw stuff but this one has me by the , well you know.














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Title: Re: husqvarna 455 rancher
Post by: ub54 on April 26, 2014, 05:59:04 pm
It's not a Rancher2, s/n 08  0500070  numbers under 455 are 965 03 02-00 if that helps.
Title: Re: husqvarna 455 rancher
Post by: 3000 FPS on April 26, 2014, 10:46:03 pm
If it were me I would at least try the high and low needles out two turns.    What do you have to lose.
In fact I am curios now on how far mine are out which is the same saw as yours.
Title: Re: husqvarna 455 rancher
Post by: ub54 on April 26, 2014, 10:53:08 pm
I can ,but really don't think it will help. I'll do it tomorrow and let you know what happens. I've never had to have the hi speed out two turns on any other saw.
Title: Re: husqvarna 455 rancher
Post by: brokenbudget on April 27, 2014, 04:07:32 am
an 8th of a turn can make all the difference. the '1 turn out' is only meant as a starting point. not for actual top performance.
Title: Re: husqvarna 455 rancher
Post by: ub54 on April 27, 2014, 09:23:27 am
Yeah, that's what I do but this thing, well its got me. If I could I'd put a different carb in it but I can't because the intake is so weird it would have to be different too. Plus it's a pain to take out and get back in.
Title: Re: husqvarna 455 rancher
Post by: 660magnum on April 27, 2014, 10:22:57 am
The Husqvarna 455 is not normally a troublesome chainsaw
Title: Re: husqvarna 455 rancher
Post by: 3000 FPS on April 27, 2014, 11:21:06 am
I went out and checked the setting on the high and Lo on my 455 this morning.

I am at 6000 ft so I tune a little more lean.   I no longer have limiters I took them off a long time ago.

The high side was just short of 2 turns out.
The Lo side was 1 3/4 turns out.

This saw runs top notch and I have no complaints about it and keeps up with any other saw in the 55cc range.
I run an 18" bar 68dl.
Title: Re: husqvarna 455 rancher
Post by: ub54 on April 27, 2014, 04:40:26 pm
I got wrapped up in yard work today but tomorrow it's supposed to rain and I'm spending the day on it if needed. I WILL get back to you all , and thamx so far.
Title: Re: husqvarna 455 rancher
Post by: ub54 on April 28, 2014, 07:12:36 pm
Well , today I ran the 455 with lo speed set at 1.5 turns out and the hi at 3 turns out. Same problem persists. Still runs perfect at full choke , and off choke will rev up to half throttle but past that it bogs down and wants to die. So I'm right back to square one. Any other ideas ? I'm in try anything mode now. There is a bridge close by I can throw it off of.
Title: Re: husqvarna 455 rancher
Post by: 3000 FPS on April 28, 2014, 08:46:31 pm
Well , today I ran the 455 with lo speed set at 1.5 turns out and the hi at 3 turns out. Same problem persists. Still runs perfect at full choke , and off choke will rev up to half throttle but past that it bogs down and wants to die. So I'm right back to square one. Any other ideas ? I'm in try anything mode now. There is a bridge close by I can throw it off of.

Now you have to pressure check it to see if you have an air leak somewhere.
Title: Re: husqvarna 455 rancher
Post by: ub54 on April 29, 2014, 12:11:47 am
Don't have the gauge to do that, which means i'll have to take it somewhere which I hate to do. The part that get me is that because of the way the carb is set up, you'd think the leak would have to be a hole the size of a dime. Being sarcastic there of course.
Title: Re: husqvarna 455 rancher
Post by: 3000 FPS on April 29, 2014, 12:20:38 am
I have two of these saws and have not had the problem your talking about.   I have worked on a number of them in my part time job and have never seen an air leak but I did have to replace a carb on one here about 3 weeks ago.   

The way I see it is that you have an air leak or a bad carb.

  You could also take the carb off again and make sure the intake is not allowing air in or a messed up gasket.   
Title: Re: husqvarna 455 rancher
Post by: KilliansRedLeo on April 29, 2014, 08:54:13 am
You can get a vac/pressure tester from Harbor Freight cheap or make one from an old blood pressure cuff. You can spend big money for them but it is not really necessary because the pressure test is a simple matter of comparing a beginning pressure to an ending pressure over time. Husqvarna says beginning pressure is 80 kPa if after 30 seconds the reading is above 60 kPa you are good to go.
Title: Re: husqvarna 455 rancher
Post by: alsled on April 29, 2014, 09:09:58 am
Plugged hi speed oriface in carb body, fuel pump not adjusted right?
Title: Re: husqvarna 455 rancher
Post by: 660magnum on April 29, 2014, 09:17:31 am
Don't have the gauge to do that, which means i'll have to take it somewhere which I hate to do. The part that get me is that because of the way the carb is set up, you'd think the leak would have to be a hole the size of a dime. Being sarcastic there of course.










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Pressure testing . . .

http://chainsawrepair.createaforum.com/ported-saws/pressure-testing/msg38039/#new
Title: Re: husqvarna 455 rancher
Post by: ub54 on April 29, 2014, 10:33:13 am
The pump lever at the needle valve was the first thing I normally check when rebuilding a carb, this time for whatever reason I Didn't and when I did check it it was way high, to the point it was flooding out. I adjusted it to level but I may need to raise it ever so slightly.I'm going to do that in a bit. I will get back to you on that because I had been thinking of doing it any way . And thanx to all for hanging in there with me. I'll figure it out I always do .   



Title: Re: husqvarna 455 rancher
Post by: KilliansRedLeo on April 29, 2014, 11:01:33 am
Good on ya! At least you found something that may be causing your problem. A guy I once knew always said 'if you didn't find something wrong, you didn't look hard enough'! ::)
Title: Re: husqvarna 455 rancher
Post by: 3000 FPS on April 29, 2014, 11:59:30 am
The pump lever at the needle valve was the first thing I normally check when rebuilding a carb, this time for whatever reason I Didn't and when I did check it it was way high, to the point it was flooding out. I adjusted it to level but I may need to raise it ever so slightly.I'm going to do that in a bit. I will get back to you on that because I had been thinking of doing it any way . And thanx to all for hanging in there with me. I'll figure it out I always do .



Let us know what you come up with so the rest of us can learn.