357xp mods

[300smag]

Hey there , my 2 cents .... I just had some questions on my 357 not long ago as I had not owned one before but had many others. I ported transfers , deleted gasket ( used permatex motoseal) and as for the muffler mod , drilled out the center baffle with a larger hole and added a gill on the side at the seam. I do not care for running any screens on my saws. I was very impressed with the power it now makes ! A great thread you can take notes with is : mastermind revisits 346xp ....

 

[Tothemax]

Thank you!

 

[300smag]

Sure thing ! I will also add but you may already know .... if using stock cylinder , use a new Caber brand piston ring and put a new wrist pin bearing in while your in there. Baileys sold me the bearing but it was listed wrong , called them and they sent me the right one , call them ? As for the Motoseal , don't use it to heavy as it will get in places you don't want it. For the gill in muffler , I just cut a slit with a cutoff disc and used a flathead screwdriver to pry out some ... Looks nice to me ! Oh , when setting the cylinder down with sealant , the intake had to be installed before tightening for clearance.

 

[Tothemax]

Awesome. I will be using the stock cyl and piston for now. May try that 272xp cylinder later down the road.

 

[jr27236]

I just recently did.my 357xp. I deleted the gasket also used same motoseal. If you have the plastic clamp around your intake get the new one and install while you have it apart, if you intend to these mods.

Heres what I did to my muffler to finish it off below.

 

[Tothemax]

Looks great.

I already upgraded the intake clamp and removed the auto decompression valve.

 

[jr27236]

Looks great.

I already upgraded the intake clamp and removed the auto decompression valve.

I left my decomp in, why did you plug yours?

 

[300smag]

I removed my auto decomp valve also , found a small crack in the hose . I was excited to get the saw together and put sealant on the intake clamp ... No leaks

 

[Chainsaw Jim]

I left my decomp in, why did you plug yours?

The auto decomp is not the manual decomp button you're thinking of. It is a rubber hose that connects from the decompression valve hole to the lower transfer area of the cylinder equipped with an automatic valve you don't need to touch. The barb Husqvarna chose for the rubber hose is too long so it causes the hose to crack when it flexes against the tip.

 

[Tothemax]

Yep. It was actually part of a tsb if I remember correctly. They also tended to carbon up and stick.

 

[sunfish]

Never leave a auto decomp in place on these saws.

 

[Tothemax]

So I finally got around to pulling the saw apart. I plan on boring out the center of the muffler baffle as much as possible and then welding a 1/2" id exhaust pipe to the top left corner of it.

I wanted to confirm a few things on the cylinder before I start in on it. First, in the picture I have a screw driver pointing at an area where the port doesn't mate up to the crankcase. Is this what you guys are talking about matching up? I would bore the cylinder out to match the case?

Next is the exhaust port on the jug. It looks fairly "clean". I can see someone scraped it with a screwdriver in the past. It doesn't look to me like it's been ported. If I take 1/8th " off all around the port, that should be enough, correct? Do I keep the actual size the same where the jug touches the piston or do I open it up 1/8th as well and taper it out like the factory?

Thanks

 

[Tothemax]

Also, I plan on checking squish and removing the head gasket. I have some high temp.black rtv sealant that should work fine as a gasket.

 

[Tothemax]

From the videos I watched you can expand the exhaust port width wise (not past the piston skirt but not height wise.

On the air intake side you clean up the imperfections.

As far as the transfers (I learned the proper term) it showed them being bored out ever so slightly and being cleaned up and much as possible.

Does this sound right?

 

[jr27236]

I never done this work before but on the intake side, I saw once that keeping it as is, is the way because it's helps atomizer the gas? And polishing the exhaust side to help flow out.
Yes to only widening the exhaust also or you catch the ring on the bottom or top. There are many 357 discussions I bet due to it being such a popular saw. My thread took off. I just did the squish and muffler mod only.

 

[old guy]

Put the base gasket on the cyl, this will show you how much you have to grind to match the case, you have to do a lot more reading before you start screwing up a good 357.

 

[71dart]

Also, I plan on checking squish and removing the head gasket. I have some high temp.black rtv sealant that should work fine as a gasket.[/QUOTE


Just be sure that the sealant is fuel resistant.

 

[67L36Driver]

Example of a ten minute muff mod with a Dremmel and cut off disc.

Muffler removal is an option.

Outlet area is adjustable.

 

[Tothemax]

Put the base gasket on the cyl, this will show you how much you have to grind to match the case, you have to do a lot more reading before you start screwing up a good 357.

I've read, I'm just over saturated with info. Its time to start cutting...

 

[Woodyjiw]

Looks great.

I already upgraded the intake clamp and removed the auto decompression valve.

I removed my auto decomp valve also , found a small crack in the hose . I was excited to get the saw together and put sealant on the intake clamp ... No leaks

The auto decomp is not the manual decomp button you're thinking of. It is a rubber hose that connects from the decompression valve hole to the lower transfer area of the cylinder equipped with an automatic valve you don't need to touch. The barb Husqvarna chose for the rubber hose is too long so it causes the hose to crack when it flexes against the tip.

First off sorry OP, I'm not trying to hijack your thread but does it take a special fitting to plug the decomp? I picked up a 357 last fall but haven't put much time on it, it had been sitting for a while apparently and when I ran it it seemed to warm up and not run properly. I assumed it had crap in the carb, gummed up, maybe bad fuel line and filter. I replaced all that with new air filter and plug but still acted up.
It would bog down when I hit the throttle and wanted to die as well. I took it into a shop to have them check it out and they went through it I got it back and it seemed fine till I ran it hard then started acting up again. I took it back they went through it again, cleaned carb and tried a new plug and I ran it yesterday. Started fine but had the bog for a lil bit when it was cold, once I got it warmed up good it cleared up and ran like as scolded dog!!! Very impressed with this saw!!!

Does that sound like the decomp acting up? I'm not against plugging it if it will save me some headaches down the road.

By the way this saw is very clean and I don't think it has a lot of run time on it.

I'm wondering if it was the decomp from the get go, maybe stuck from sitting?!?

Yep. It was actually part of a tsb if I remember correctly. They also tended to carbon up and stick.

Thanks for the info in your thread, keep it coming.