Husky 390XP in poor health

[spudulike]

I would stick a new piston in it. I think you will be surprised with how well it will work. 

The damage under the port looks light and is much less likely to cause issues than the inlet side which would cause lots of blow back and leakage on crankcase primary compression.

If you haven't, lightly hone it with a rotary hone and see if you can get a Meteor, Hyway or Golf/Vec piston in that order! 

Engines don't see that the bore isn't visually pleasing. They just work on compression made hot and cold etc.

Make sure you pressure and vac test then service the fuel system and tach the saw a bit rich to let it all bed in!

[AngrySquirrel]

Meteor cylinder piston kit for Husqvarna 390 390XP 385 55mm Jonsered 2188 2186

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Fits Husqvarna chainsaw models 390 390xp 385 and Jonsered chainsaw models 2188 2186.

 

Piston Kit fit HUSQVARNA 390XP, 390XPG, 390 EPA (55mm) [#537420202]

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390 EPA (2006-10). 390 EPA (2010-05). 390 EPA (2011-05). Protect your valuableHUSQVARNA machine.

 

[bmp01]

1 hour ago, spudulike said:

I would stick a new piston in it. I think you will be surprised with how well it will work. 

The damage under the port looks light and is much less likely to cause issues than the inlet side which would cause lots of blow back and leakage on crankcase primary compression.

If you haven't, lightly hone it with a rotary hone.....

It's had a real good chemical clean and a fair bit of abrasion to get to where it is now. Any other cylinder I've done would be as clean as a whistle by now.

Just rebuilding it with a new piston is an option, see if it survives,  then pull it apart for some tuning work. They come apart pretty quick.

 

On the other hand new OEM 385XP cylinders are available on eBay for reasonable money.  

Do both...

[spudulike]

I would slap in a Meteor £40 piston, do all the ancillary work I mentioned earlier and put some hours on it. 

Big engines suffer a lot less from this sort of thing compared to smaller engines. 

You should be able to delete the base gasket as well which should help but check the squish first.