Chainsaw Repair

Husqvarna - Stihl - Poulan - Jonsered - Dolmar chainsaws and more => Husqvarna => Topic started by: Nathaniel Vansickle on December 18, 2014, 12:34:31 pm

Title: Husqvarna 55 intake and impulse
Post by: Nathaniel Vansickle on December 18, 2014, 12:34:31 pm
i need a little advice on these saws and saws with similar intake setups. i have one on the bench now getting a tuneup. New piston and ring plus fuel system and intake boot. need some tips on getting these things to seal up and pass a pressure/vac test. i cant get the intake to seal past 4-5psi. in the past i have tried 518/515 on that boot with no luck. before i assemble them i wipe the cylinder, plastic divider, and boot with alcohol to clean the oil off and act as a lubricant when assembling them. Is 5psi acceptable or should these saws hold more? i normally only test to 7psi.
Title: Re: Husqvarna 55 intake and impulse
Post by: Cut4fun on December 18, 2014, 12:40:20 pm
Did you replace the impulse seal?

(http://www.ereplacementparts.com/images/husqvarna/55_(1990-01)_WW_1.gif)
Title: Re: Husqvarna 55 intake and impulse
Post by: Cut4fun on December 18, 2014, 12:43:07 pm
 Husqvarna impulse seal tube pipe 505310751

(http://www.hlsproparts.com/v/vspfiles/photos/505-31-07-51-2.jpg)

Title: Re: Husqvarna 55 intake and impulse
Post by: Nathaniel Vansickle on December 18, 2014, 12:55:11 pm
sure did. 505310751 and 503161602 are both new. the divider is not new though. i have ran into this a few times on different saws that use this style intake. it is the intake boot that leaks on them. i have used gasket sealant No.2 with success and no comebacks but wondering if there is a better way or if i am being to picky on these
Title: Re: Husqvarna 55 intake and impulse
Post by: aclarke on December 18, 2014, 01:53:38 pm
Does I hold vacuum? I don't think that "rubber band" sealing ring on the intake has enough tension on it even when new to hold much positive pressure
Title: Re: Husqvarna 55 intake and impulse
Post by: Nathaniel Vansickle on December 18, 2014, 02:13:46 pm
yep they hold vacume fine. its just pressure that is getting me. the latest 55 will hold 4-5 psi but not 7
Title: Re: Husqvarna 55 intake and impulse
Post by: Eccentric on December 18, 2014, 02:32:33 pm
If it holds vacuum fine and consistently holds 5 psi it's probably OK.  That really is a crappy intake setup.  Why HVA stuck with it through so many different saws I'll never understand.  Cheap to manufacture I guess.....
Title: Re: Husqvarna 55 intake and impulse
Post by: Nathaniel Vansickle on December 18, 2014, 05:18:24 pm
well i guess i will lower my standards on these saws and turn them loose at 5psi.
there are alot of saws that they used this or a similar setup on along with their trimmers. I have never cared for it but always managed to get them to pass a 7psi test by either just replacing everything with new or adding that No. 2 sealant to the new parts but i wondered if there was a better way. No.2 sealant is a flexible, non hardening, fuel resistant sealant but i have never felt comfortable using it. always feel like i am half a**ing it when i resort to that stuff.