new to me 371 xp, or is it..... ?

[peacmar]

Recently I pick up a 371xp from flea bay and when I received the saw my "good deal" feeling was pushed aside when I opened the package and discovered I had not received the saw pictured in the listing. I first noticed the serial tag was missing and that the plastics where all different shades and different scratches that didn't line up. Contacted the seller, zero communication, got a bad feeling about the saw and contacted authorities in the area it came from and after a couple weeks of waiting was able to verify by them that bit wasn't stolen. So now I sit wit this thing, not as pretty as I expected. But surprisingly runs like a champ. Didn't have to adjust the carb, 4 pulls to start from dry. 162 psi compression and doesn't fade when its been good and heated up. And as I had purchased this saw to make a project out of it I didn't feel like I was in too bad of a position considering it only cost me $245 to get it to my front door.

Which leads to to my question.
Is there a way to know what displacement this saw is without pulling the jug and measuring the bore?

I know that everything in this family of saws is interchangeable so anything on the outside is trivial at this point as it has clearly been changed out. Some things I haven't spent more than 20 minutes with the saw actually looking at it yet but here are some things I've noticed that may help.

Large bar mount
Brake cover tensioner ( outboard not inboard)
Short top air filter
Cylinder was made by mahle
Comp release on clutch side of cylinder

I put my 28" tsumara bar on it with a full comp chisel chain and hurried it in a piece of red oak and it seems to pull with some athourity so I imagine it has the larger displacement top end.

I plan to mod the muffler some time next week so if there is anything I might be able to see inside that may help identify that would be great to know.

 

[Jacob J.]

What are the numbers on the side of the cylinder?

 

[buck futter]

you just nee to pull the muffler to check the bore. put your calipers on the ex flange. roll the piston to the up position zero out the calipers when the caliper tail hits the piston. roll the piston to bdc measure to the other wall.

David

 

[gunnusmc03]

If you feel the seller misrepresented the item for sale contact paypal, they usually side with the buyer and you will get your money back.

 

[SawTroll]

The only top end sizes that rules out is the 362xp one and the open port 365 one. Even the Mahle casting numbers will be the same on the 48, 50 and 51.4mm ones.

Is there a number in blue ink on the top of the cylinder?

 

[Jacob J.]

The only top end sizes that rules out is the 362xp one and the open port 365 one. Even the Mahle casting numbers will be the same on the 48, 50 and 51.4mm ones.

Is there a number in blue ink on the top of the cylinder?

Mahle put some codes on the side of the cylinders that differentiate between the 48, 50, and 51.4mm cylinders. So it's actually pretty easy to tell them apart.

 

[peacmar]

Well thank you for the overwhelming responses. I'll look for the numbers on the cylinder this afternoon when I get home. I also never thought about reaching to the back of the cylinder with the tail end of a calipers.

I thought about contacting PayPal, but then looked up the cost of a case And all the other parts and thought to myself that I still am happy with what I got and really don't want to sending back. I've been playing with snowmobile motors for years and find saws to be just as entertaining. I plan on trying my hand at porting and whatnot else with this saw as I've played with a few garage sale specials already and found what to do and not to do. So I'm not to concerned with that fact that I may have not gotten the 371 any more. I just am curious to know what I do have. I rebuilt and modded an old husky L65 over the winter and was very pleased with the results. The sale of that saw is paying for this project so if I have to invest in the larger displacement top end I won't be too disappointed. I only chose the 371 because of its availability of parts and support from the members here and the knowledge available. Of course i felt the need to have a larger saw on hand also....

I'll loom for those numbers this afternoon and get them up here asap.

Thanks again

 

[SawTroll]

Mahle put some codes on the side of the cylinders that differentiate between the 48, 50, and 51.4mm cylinders. So it's actually pretty easy to tell them apart.

They all are marked 50ZK6, and I know the 51.4mm ones have another code as well - but what is the clue to 48 vs. 50?

 

[peacmar]

No blue ink on the cylinder that I can find.

Mag side of the cylinder has a V and a 6h on the upper part of the transfers and the lower part
Says 50zn 21 with what looks like a + above the 21 followed by a W1

Walbro carb if that matters, not sure if that's original...

 

[SawTroll]

....

Mag side of the cylinder has a V and a 6h on the upper part of the transfers and the lower part
Says 50zn 21 with what looks like a + above the 21 followed by a W1

.....

That means the cylinder originates from a Jonsered saw in the same "family" of saws, but it still could be either 50 or 48mm (based on 50ZN21).
I don't know what "+ W1" means though, JJ might know?

 

[peacmar]

Well this just keeps getting more and more interesting. Whoever frankenstiened this thing together did a very good job of it. Not sure what their intentions where. I noticed that the case originally had the inbound tensioner. And that the case appears to be an original husqavarna. No evidence of repainting or removing any other paint where some of it is chipping on the underside. I may have to pull this thing apart much sooner than I originally wanted to just to satisfy my curiosity. Still looking at this as a good basis for a fun build. Lots of bugs to work out. Simple things like stripped or missing screws. Recoil cover is cracked. When I've made it a reliable runner and put some hours on it then I'll start worrying about the build. Thanks again guys. I'll post what I find on the cylinder bore when I pull the muffler off next week and if somebody knows what those last digits on the cylinder mean that would be great.


On another note. Ran it for about ten minutes tonight and noticed that the power band is really narrow. I tried to get an rpm reading but my tach was acting goofy and wouldn't pick up consistently, but I noticed that if I overloaded the saw it completely fell on its face. No low rpm grunt at all. Is this typical or could it be a function of port timing in the unknown cylinder. Most saws i have used could start a chain spinning even after it has stopped and dug in. Not happening with this one. Power is very very narrow. Unless the ports have been touched.....

 

[SawTroll]

Bump!

It is too early for this thread to fade away....

Those saws shouldn't act like that, regardless which size the top end is - something is wrong! The first I would check is the carb setting and the condition of the top end.

 

[peacmar]

I'd hate for this thread to die off too.... I have to chronicle a build at some point and would love to reference how it all began.

I'm thinking carb problem myself. I only had about ten minutes of safe use able light last night again and was able to recreate the circumstances. No effect or change based on how warmed up the saw is and comp is still 162. Plug looks pig rich but no to little smoke and 4 strokes perfectly. The weird area is mid and low. If i let off in the middle of a cut it dies right off. The. only starts again with a little coax from the throttle. Mid range half throttle cutting showed the rich condition. Would act as though the choke was being pulled on a warmed up saw if I touched the chain to the wood. Blip the throttle to clear it out and away it went.

I'm strapped for time lately with work so I asked a friend who's runs a small engine repair shop to give the carb a once over next week. I also have to get a new recoil cover. This one cracked while i was messing with it last night and both top screws no longer support it so starting has become almost impossible if I'm going to be safe.

Ill check back in in a couple days when i get the new recoil and really start to get into this thing. This will be the first time ive torn a saw down completely so im sure ill have plenty of questions.

 

[peacmar]

Well the carb deffinatey needed to be rebuilt. I don't work on these small carbs myself as my hands are too big and clumsy but my buddy came over and went through it in exchange for a few beers and some shop talk. Not sure exactly what he replaced but he said it was causing too much fuel to dump in near the low end. Makes sense after what I was seeing in the cut. So now it starts third pull from cold and hardly a full pull when warm. Idles nice, very snappy and responsive and sings a nice tune full throttle. Next project is the recoil and kill switch when the parts arrive on mg door step. Then it'll be muffler mod and I'll be able to tell you guys what bore that cylinder is.Does anybody happen to know the con-rod length and stock port timing numbers for the 371xp? I'd like to check the timing of this odd jug and see if its the same as a husky one and with the rod length i only need to drop a dial indicator down the plug hole for crank degrees

 

[peacmar]

Its a 50 mm bore

Well took the muffler off tonight to start the mod and measured the bore. 50.16mm through the exhaust port with the tail end of a caliper. Not as perfect as a bore gauge through the bottom but good enough. So we have a 50mm bore jonesered cylinder from who knows w:hat on there and a double ring piston. At 162 psi comp it runs like a raped ape in the cut even with a 28" full comp chisel chain. Very happy so far. Looking forward to my oiler parts showing up and getting back out with it. This winter when it comes apart I'll be checking port timing and maybe find a little more bout about this cylinder.



not sure how much of a deal I'm at yet, but all things included- saw,case of beer for carb rebuilt, brand new oil pump and all associated parts, my grand total to date is $295. Sold the old l65 for $300 ready to cut so I'm about to break even.

Best upgrade yet! Already ready to start looking for another....:msp_tongue:

 

[elanjoe]

Souns like a jonsered 2071 or 2171 cylinder, essentially the same as 371 /372 but porting may be different

]

 

[SawTroll]

Good feedback! :msp_biggrin:

The twin ring pistons were used in the EPA Versions, but it could of course be a replacement. Not a big deal anyway, but most will prefere the single ring version, given the choise.

 

[peacmar]

Souns like a jonsered 2071 or 2171 cylinder, essentially the same as 371 /372 but porting may be different

]

That's exactly what I was thinking. I also, after a couple weeks, heard back from the seller. He stated that the saw was freshly rebuilt just before he bought it from a local shop. Looks to me like he hardly used it, and never cleaned it, but that's half the fun. I may have a few pounds of shavings to scrape out of my parts cleaner but the first fire on the patio will take care of that.

I can see why these saws are such favorites. Lite and snappy right out of the box. I work tree removal part time in the summer for the local township and will deffinately have this saw on the truck. I imagine with a 8 pin and a short bar I'll be flying through the chips like nothing.

 

[elanjoe]

Sort of a boring thread without a picture . perhaps you could upload one ?

 

[SawTroll]

Souns like a jonsered 2071 or 2171 cylinder, essentially the same as 371 /372 but porting may be different

]

I don't really think the porting is different, but I have been wrong before.