Chainsaw Repair

Husqvarna - Stihl - Poulan - Jonsered - Dolmar chainsaws and more => Husqvarna => Topic started by: alsled on October 30, 2013, 07:08:34 pm

Title: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: alsled on October 30, 2013, 07:08:34 pm
What brands are good and where to get them?  I looked on ebay and see a lot of hong kong and china products, I'm sure that is low quality.  Who makes decent aftermarket cylinder, piston and rings? For the 372 and 390xp.

Thanks
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: KilliansRedLeo on October 30, 2013, 07:14:57 pm
I use one of two brands from hlsproparts.com

Meteor or Hyway, never had any problems with either.

If your saw is a 372 I would use a Hyway 372 BB kit (52mm bore) and substitute a Meteor Stihl 064 piston for the BB kit piston.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: alsled on October 30, 2013, 07:30:38 pm
Whats the difference between the two pistons?
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: alsled on October 30, 2013, 07:32:52 pm
I searched hisproparts and nothing came up?
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: Cut4fun . on October 30, 2013, 07:38:44 pm
Right here.  10% off   http://chainsawrepair.createaforum.com/used-chainsaw-parts-online/10-off-on-your-next-order/
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: 660magnum on October 30, 2013, 07:39:43 pm
http://www.hlsproparts.com/small-engine-cylinder-rebuild-kits-s/138.htm
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: Cut4fun . on October 30, 2013, 07:56:24 pm
Caber rings are my 1st choice for rings, if not oem.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: alsled on October 30, 2013, 07:59:37 pm
Thanks!
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: alsled on October 30, 2013, 08:31:50 pm
what about NWP products, any good?
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: 660magnum on October 30, 2013, 08:36:08 pm
The products are generally OK but for the eastern USA/Canada the shipping will get your goat compared with HLSPRO.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: alsled on October 30, 2013, 08:42:06 pm
Do these aftermarket companies keep the same port timing? or do they change things?
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: 660magnum on October 30, 2013, 08:43:25 pm
They are pretty close
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: SawTroll on October 31, 2013, 12:40:21 am
Do these aftermarket companies keep the same port timing? or do they change things?

Aftermarket cylinders tend to have ports that are narrower, which is a negative factor. I can't comment on the timing, but it likely varies.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: mdavlee . on October 31, 2013, 08:10:57 am
Timing will vary on the cylinders. Some are as good and occasionally better. I would probably stick with OEM for the 390 since there's not many choices there. You can get an OEM cylinder from spike60 for a better deal than anywhere online. Be worth checking into. I think one of those aftermarket 390 pistons didn't last long for a member in BC. The 372 has a lot of choices and a lot of them seem to be fine. Check with weedeaterman.com for aftermarket parts.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: KilliansRedLeo on October 31, 2013, 10:26:14 am
Whats the difference between the two pistons?

Both the BB kit piston and the Stihl 064 piston are 52mm. The Stihl 064 piston it taller by approximately 1.3mm and can be used to raise the CR to above 190PSI. I have done several for customers and the saws run well, with no problems so far.

The Stihl piston has the same 12mm pin as the Husky however a few thousandths must be removed from the inner sides of the piston pin boss in order to clear the small end of the rod and you must make sure that you have about 2mm clearance at BDC for the crank throws. A machine shop can remove the metal from the piston, my gunsmith does it for me, quicker and cheaper.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: 660magnum on October 31, 2013, 10:44:33 am
I have a 372 set up this way.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: alsled on October 31, 2013, 12:37:01 pm
190 psi. Can you still run 91 octane pump gas on that?  I do a lot with snowmobiles and they would never live at  190 psi. Lots of detonation, like instantly.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: KilliansRedLeo on October 31, 2013, 02:14:56 pm
Never had a problem. I have customers who run 91 e10 with out a problem also others who run pure gas as well as SEF and no problems yet.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: alsled on October 31, 2013, 02:26:33 pm
That's good to know. Just wondering, is there a huge difference in 190 and stock compression, as far as torque/ hp, plain old grunt feeling ?
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: 660magnum on October 31, 2013, 02:37:43 pm
They sometimes build up more heat.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: KilliansRedLeo on November 05, 2013, 11:48:02 am
Normally, when I do one of these BB/Stihl saws I also do a dual port muffler which seems to control the 'run hotter' situation. I have even been known to substitute the carb off a 372XT (Walbro RWJ-4) or the carb off a 390XP, both are bigger than stock but you would only note a difference on a stopwatch. In order to change to either of these 'Tillotson' mount carbs the intake setup has to be changed, not hat big a deal but a PITA to find all the correct parts.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: alsled on November 23, 2013, 04:20:00 pm
Well i bought a 52 mm hyway BB kit for a 365.  Plus a sthill 064 meteor piston

I posted these two pics show the difference in height, the meteor is about .015 taller in this case, not 1.2mm  Quality controll issues Tim, as you found yours to be 1.2 mm different?? about .047



Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: KilliansRedLeo on November 23, 2013, 04:31:16 pm
It appears that you are comparing the BB piston to the Stihl piston. When I quoted 1.2mm I was comparing the stock 372 Mahle piston to the Meteor Stihl 064.

Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: KilliansRedLeo on November 23, 2013, 04:46:20 pm
Here are the specs for the Meteor replacement for the standard 372 Husqvarna piston:
 
Fits the following chainsaws:
Husqvarna 371, 372*
Jonsered 2071, 2171

Note This is a single ring piston, 372 EPA saws come with a pair of (50x1.2mm) rings. This piston will fit the the two ring models
Replaces Part Number 503 69 12 71

Bore 49.96mm
Height 42.5mm
Head Type Flat
Piston Pin 12mm x 36mm x 8mm
Ring 50mm x 1.5mm (Caber F-Cast GH.F)
Compression/Pin Top to top of Piston 16.5mm
Compression/Pin Center to top of Piston 22.5mm

Here are the specs for the Meteor replacement for the Stihl 064 piston

Fits the following chainsaws:
Stihl 064, MS 640

Replaces Part Number 1122 030 2001

Bore 51.96mm
Height 43mm
Head Type Flat
Piston Pin 12mm x 33mm x 8mm
Rings 52mm x 1.5mm (Caber F-Cast GH.F)
Compression/Pin Top to top of Piston 17mm
Compression/Pin Center to top of Piston 23mm

Depending on your numbers your may be able to get optimal squish and not have to use a base gasket.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: alsled on November 23, 2013, 07:42:02 pm
Tim, 

Well I put the big bore kit on, no base gasket and the 064 meteor piston, squish came out at .022, I tried doing a compression check but almost knocked myself out, I'm at 180 with the decompression valve open.  I'll be dis- assembling and installing a .015 base gasket on Sun.

I know you said 195 is where they really run good, but how the hell do you start it?

This BB kit is on the 365 special I brought from you.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: KilliansRedLeo on November 23, 2013, 09:58:58 pm
Well, your a bigger guy than I am, I have the same saw and I can start it without problem. 200psi is a lot, but it only takes a couple of short pulls to get mine going! Check your timing.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: 660magnum on November 23, 2013, 10:09:12 pm
I have a 372 set up this way with the Meteor 064 piston and for an old man I don't have any trouble starting it. The saw runs strong.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: KilliansRedLeo on November 23, 2013, 10:10:16 pm
Grit your teeth and get the saw running, get it to idle, then let it run until it runs out of gas. After that it should be easier to start.

Nobody ever said that a high performance saw was going to be a 'home owner' cake walk saw to start.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: KilliansRedLeo on November 23, 2013, 10:15:34 pm
660, +1, I am also an 'old fart' and have no problems either. These are really good running saws! I think Al will be fine as soon as he gets used to the saw and its starting quirks.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: alsled on November 24, 2013, 08:07:15 am
Tim and 660,  question for you both.  Are either of you using a base gasket or copper shim?   And what is the squish on your saws? 

Also, I did not try to start it yesterday, wanted the gasket in a tube to set up before fuel gets at it.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: mdavlee . on November 24, 2013, 09:33:10 am
If you used a good bit of assembly lube on the rings it could be reading a bit high. Run it as is and then check it after it cools down again.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: KilliansRedLeo on November 24, 2013, 09:50:03 am
Tim and 660,  question for you both.  Are either of you using a base gasket or copper shim?   And what is the squish on your saws? 

Also, I did not try to start it yesterday, wanted the gasket in a tube to set up before fuel gets at it.
Al, I am running no gasket, (Yamabond4) and been a while since I built that saw but my notes say that the target was .020 and I settled on .023 and 198PSI. I am going to build up another one for a customer after the holidays, I let you know the numbers on that saw also.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: 660magnum on November 24, 2013, 10:45:49 am
I didn't put my saw together and have no clue but always assumed it didn't.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: alsled on November 24, 2013, 10:48:39 am
I did put a lot of oil in the jug befor pulling it over.  I also had no bar on it.  put bar on it and with the oil drained out I can pull it no issue.

Next new problem, can't keep it running, I turn the low speed adjustment screw 5 turns out and it does nothing, its running lean, now to take the carb apart.  This bugger is slowly testing my patience.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: Cut4fun on November 24, 2013, 11:15:57 am
I didn't put my saw together and have no clue but always assumed it didn't.

If your talking about the 52mm big bore with 064 piston. Snoopy put that saw together. I think he used Threebond 1194, but you would need to look. I know it's sealer, just not sure what he used.  (or maybe my mind dont remember and is wrong)  :-[ :D
I measured it but dont remember. The squish on that one could still be tightened a little (take off the base). But seen no reason to on a work saw.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: 660magnum on November 24, 2013, 11:17:20 am
In a lot of the after market cylinders, The nipple for the impulse line is loose in the bottom of the cylinder and you may have a air leak in that area? Sounds like a air leak or you have pushed sealer material up over the end of the impulse line inside your cylinder and the pump in your carb is not working well?
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: alsled on November 24, 2013, 11:19:08 am
Pulled the hi and low speed screws out, shot some carb cleaner through it all is good!

I have the BB and the 51 with a new piston and ring idling outside  right now.

When the BB cools down I'll check compression.
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: alsled on November 24, 2013, 11:20:39 am
660, I blew air through the impulse line after assembly to clear out the passage just in case.  the carb had some crap in it read my post above
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: KilliansRedLeo on November 24, 2013, 08:32:19 pm
OK, the BB had to have run out of fuel by now. So, what is the latest?
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: alsled on November 24, 2013, 08:36:13 pm
All seems good Tim, got the bugs worked out, need to put it at some wood.  Didn't check the comp after it cooled down, I got into some other things.   
Title: Re: Who makes good cylinder, piston rings, for 372 and 390xp's?
Post by: Spike60 on December 20, 2013, 01:00:22 pm
Some good prices and some not so good out there. When choosing an aftermarket kit, pick something that has a good track record. Some of it's great, and some is pretty awful.

I sell the OEM 372 kits, including the XPW for just $200. Believe it or not all four kits for that chassis are priced within just a few bucks of each other.