Thread: Chain slack driving me crazy......

Originally Posted by avalancher

The chain can be slack enough to have a droop, but if you turn the chain by hand, it will tighten back up to the point that you cant turn it any further by hand around the bar.

I have experienced the exact same thing, only difference it's on my Stihl saws!!!

I bought a new 15" Stihl bar for my 026, and a new 16" Stihl bar for my 250 together with 2 26RMC and 2 26RSC chains, and the purpose was to be able to switch chains between the two saws (the bars are actually the same lengths). I also got a new clutch drum and rim setup for the 250 and a new rim for the 026.

However, I was close to going berserk when trying to tighten the chain, it just wouldn't do! If I go back to the old bars, chains and drive sprockets the problem is gone, so whatever it is, it does not seem to be the saws.

I was just out in the shed checking on the 250 and the difference is quite big: When the chain is the most saggy the whole drive tang comes out of the groove, and when it's the least saggy the chassis of the chain are flush against the bar rails. I'm pretty sure both saws were the same, but for now I only confirmed on the 250.

As I couldn't find an explanation to this I decided to just don't care, I've tightened the chain so that it still rotates freely from hand power, and it hasn't been thrown yet. Don't look too good but since it cut's wood I'm just ignoring it.

I listened to all your suggestions, and here is what i did to eliminate what I could.
First, took both bars off, cleaned all the rails and dressed them. Greased the nose sprocket, cleaned the oil ports and inside the side cover. Blew it all out with compressed air. Ran both saws with the nose down at a piece of cardboard, both spraying oil.
Next, I called the shop where i bought them, and had the read to me what it said on the spool. .375 pitch, .050 gauge.
Then I explained the problem to the owner. He said it was the sprocket.
Naw, maybe on the 372, its getting a little worn, but the sprocket and the bar on the 455 have less than 10 hours on both. Replaced them both at the same time last month.
he said, oh, you have sawdust stuck in the front nose sprocket. On both saws? Yep, thats it. Explained that I cleaned everything out, blew it out, and reassembled everything. Also, both saws running full chisel do the same thing, they both work fine until I mount the semi chisel.
he then said something really stupid like maybe my saws were not set up to run semi chisel......
then I asked him why every oregon chain I have ever had in my lifetime had markings on the drive tabs, and these chains do not. Had him look on the spool that he had, no markings on the drive tabs. Then had him look at all the rest of the oregon chain that he had in stock, all had markings on the drive tabs.
I am beginning to suspect that someone coiled a chain other than what was supposed to be on that spool, and sold it off. On purpose? dont know. I told him that i would be down there in the morning with both saws in tow so that he could take a look at em.
Thanks for all your suggestions and thoughts on the matter. I will post what comes of it tomorrow morning.

Oh, and by the way MCCALL, that little bug down in your signature drove me crazy! Thought it was a bug on my screen, took two stabs at it before I realized that it was a ghost I was chasing.

Originally Posted by huskydave

+1 check the box .404 instead of .375.

I don't think it's 0.404 as it's (0.404) 0.063 gauge (or 0.080 harvester) and would not fit the bars 0.050 gauge groove.

Any chance he sold you a "picco style" 3/8 0.050 ? Picco runs different sprockets.

Originally Posted by Mad Professor

I don't think it's 0.404 as it's (0.404) 0.063 gauge (or 0.080 harvester) and would not fit the bars 0.050 gauge groove.

Any chance he sold you a "picco style" 3/8 0.050 ? Picco runs different sprockets.

Okay, you are going to have to educate me on this one, what is a Picco style chain?
Please excuse my ignorance! I have heard the term, but dont know what it is.

You can check the pitch right now. Just measure center to center between any 3 rivets in the chain and divide by 2. Do it on the FC chain that works and the new SC chain that doesn't and compare.

Chris

Originally Posted by avalancher

Okay, you are going to have to educate me on this one, what is a Picco style chain?
Please excuse my ignorance! I have heard the term, but dont know what it is.

See:http://stihlusa.com/chainsaws/types.html

Note that the link above does not list the 0.050 3/8 picco but it is found on the chain suggestion guide on sthil's website. It is a low profile chain that produces less kerf and needs less HP to pull. Made for small saws/limbing saws but also works good on larger saws used for milling when set up with proper bar/sprockets and ground to ca. 10 degrees.

I'm not sure if other brands of low profile chain requires different sprockets but I'm sure someone here will fill us in soon.

Originally Posted by avalancher

Okay, you are going to have to educate me on this one, what is a Picco style chain?
Please excuse my ignorance! I have heard the term, but dont know what it is.

Low Profile 3/8" chain, made for the smallest saws around.

They have different drive tangs from the regular 3/8 chains, and require different sprockets.

Originally Posted by avalancher

There is no stampings on the drive links, even though this is supposed to be an Oregon chain. The box was handwritten 72LG84. I thought the 72 series was .050 gauge. If the gauge was too big, it wouldnt fit between the rails, would it?

Something obviously doesn't add up, as LG is chisel, not semi-chisel.....

Moron dealer, most likely is part of the issue!

Originally Posted by SawTroll

Something obviously doesn't add up, as LG is chisel, not semi-chisel.....

Moron dealer, most likely is part of the issue!

Ah, you may be on to something here, I looked at several boxes(empty ones) in the toolbox on the truck, and they too have the same 72 series listed. they were full chisel like you mentioned. Maybe the "moron" part is a little more applicable than I first suspected here.

I am familiar with a low profile chain, in fact I have a few when running the 372 on my mill, and they are very different than these semi chisel. I didnt know that the term picco referred to to these chains. Thanks for the info! Learn something new every day.

Originally Posted by avalancher

Ah, you may be on to something here, I looked at several boxes(empty ones) in the toolbox on the truck, and they too have the same 72 series listed. they were full chisel like you mentioned. Maybe the "moron" part is a little more applicable than I first suspected her

The 72 would be the same for chisel or semi in 3/8 /.375 pitch and .50 gauge. It's the LG that designates chisel. You want MLP (newest Oregon semi) or MJP older stock called Super 70 Multicut.

Can you possibly post a picture of the chain?

Originally Posted by Zodiac45

The 72 would be the same for chisel or semi in 3/8 /.375 pitch and .50 gauge. It's the LG that designates chisel. You want MLP (newest Oregon semi) or MJP older stock called Super 70 Multicut.

What he really needs is Stihl RM/RMC!!!

Originally Posted by Zodiac45

The 72 would be the same for chisel or semi in 3/8 /.375 pitch and .50 gauge. It's the LG that designates chisel. You want MLP (newest Oregon semi) or MJP older stock called Super 70 Multicut.

Multicut is not SEMI CHISEL it is full chisel but with more layers of chrome. Semi chisel 72 chain is DG which has a pattern like LG or DP which has a pattern like LP



Scott

This post is interesting because recently I solved a chain issue on a Stihl 031AV. Owner said the saw never has in years at least, cut straight. I checked and sure enough he has .050 on a .063 bar. then I got to thinking.... in past times never has any shop that ever made me a chain asked what gauge bar I was using. luckily my bars where all .050 and the chain was too. I now make my own so I know what I've got. Also we recently caught a bad rivet job and a chain made at a dealer. It was ready to break when I caught it.

I wonder if these shops just really don't know or just don't care if they can make a sale?