Cylinder marks, How much is too much?

[Martinm210]

So before even getting the last of my 066 parts back to complete my first saw build, I bought another parts saw, this time an 044.

Anyhow, the 044 has bad crank bearings, but the top end looks pretty decent. The piston has a few dings on top and some light scratching and the rings look good.

The cylinder on the other hand I'm unsure about. Not sure pictures really explain it well enough, but there are several very very fine marks in the cylinder above the intake port. They don't appear to be deep enough to go through the plating, and hard to really see, but if I run my finger over the walls I can barely feel these marks. This is not aluminum transfer, it is clearly some very light scoring that is smoothed out.

I'm really tempted to buy an 046BB kit and modify it to fit this saw, but at the same time I'm wondering if this OEM jug is worth running another piston in or not. At a minimum I think I'd like to buy a new piston and rings, but I like the porting on the stock jug (It has a 12mm pin and straight fins on top).

Any suggestions for how much marking in a cylinder is considered ok?

1) No marks can be felt at all, only aluminum transfer that can be removed.
2) Light lines can be felt, is ok
3) ???

Thanks!
Martin

 

[Jacob J.]

It depends on where the marks are located. Marks around the intake port tell me that the saw was repeatedly run with an extremely dirty air filter, or somehow debris made it's way into the intake tract and got pinned between the piston skirt and cylinder wall.

If the marks only go up part way and don't affect the compression ring area, the cylinder will be fine.

 

[mattinky]

It depends on where the marks are located. Marks around the intake port tell me that the saw was repeatedly run with an extremely dirty air filter, or somehow debris made it's way into the intake tract and got pinned between the piston skirt and cylinder wall.

If the marks only go up part way and don't affect the compression ring area, the cylinder will be fine.

+1, I've seen it in dirt bike motors many times when people don't clean their filters

 

[blsnelling]

A few small scratches won't hurt you much. I've cleaned up scores cylinders that left a few small scratches and still made 165-170 PSI compression.

 

[stihl only]

So before even getting the last of my 066 parts back to complete my first saw build, I bought another parts saw, this time an 044.

Anyhow, the 044 has bad crank bearings, but the top end looks pretty decent. The piston has a few dings on top and some light scratching and the rings look good.

The cylinder on the other hand I'm unsure about. Not sure pictures really explain it well enough, but there are several very very fine marks in the cylinder above the intake port. They don't appear to be deep enough to go through the plating, and hard to really see, but if I run my finger over the walls I can barely feel these marks. This is not aluminum transfer, it is clearly some very light scoring that is smoothed out.

I'm really tempted to buy an 046BB kit and modify it to fit this saw, but at the same time I'm wondering if this OEM jug is worth running another piston in or not. At a minimum I think I'd like to buy a new piston and rings, but I like the porting on the stock jug (It has a 12mm pin and straight fins on top).

Any suggestions for how much marking in a cylinder is considered ok?

1) No marks can be felt at all, only aluminum transfer that can be removed.
2) Light lines can be felt, is ok
3) ???

Thanks!
Martin

This is a tough question to answer without seeing the part but here is my shot at it.

I think what you want to hear is that it will be fine! I also hate to say this but sometimes to some people, it depends on what they want to do with the saw. What is done on a "sending it to ebay" saw, may not be the same as what is done on a saw that you want to keep. Also, the value of saw can have a lot to do with what is done to the saw. It it's a Wildthang, you aren't going to want to dump much cash into it, so you might just give it a go and see if it will run.

If I have a cylinder that I question, I replace it, especially if it is a pay job. I shy away from the aftermarket stuff because I have to stand behind the repair and I haven't found what I would call "quality" options out there yet.

If the marks are almost superficial, I would rather run that jug than an after market one.

As far as the 460BB on the 044 crankcase, I thought there were issues with the case volume being too small to really benefit from the CCs?

 

[timberwolf]

The case volume Is not a big issue, keep in mind case clearance volume is also increased with the BB kits as the volume under the piston is increased due to the larger piston diamiter. I have put 046bbs on 044s and they work well, does take a fair bit of work to make everything fit nice though.

Porting could be beter from a performance prespective, and there are a few issues with exhaust port shape and a few batches of bad rings and c clips show up in the BB history.

Some cases esp 066 where it's not bolt on and minor trimming is needed.

If it's a matter of getting a saw running, the BB kits are a good option keeping cost down. But I would pay less for a used saw with BB kit than I would for a used saw with original parts. Some people will pay extra though...:monkey:

 

[Martinm210]

Thanks guys!

I didn't even think about the air filter, but I bet that's exactly what caused this. I got the jug all super clean degreased now, so I'll upload a couple of pictures in a few minutes.

Most of the marks are focused around the intake port, particularly the first 1/2" or so above the intake, but they do extend clear up to the squish band. There's even a few small impact marks on the squish band itself where it appears this dirt or debris was impacting.

I'm not intending to sell it on ebay right away or anything. I'd actually like to keep at least two saws, and figured on building this one right, similar to my 066 build. I have a friend that wants to buy my MS290, so I might just decide to keep this 044 and my 066 as my two work saws.

I've read a few threads on the 044>046BB conversion, while I know the aftermarket jugs are crap in comparison to OEM jugs, it would still be fun doing it.

 

[Martinm210]

Here are those pics of the scoring:

And with a piece of paper in the jug for some contrast:

I'm thinking it's new P&C time.

Anyone have any particular aftermarket P&C 046BB kits that they liked. I have to admit, I wasn't particularly impressed with my Woodlands 066BB kit, so I've been eyeballing some of the ebay kits.

Just not sure any one would be better than the others. I'm willing to spend a little more for better quality, just not up for spending OEM prices. Besides my dealer is terribly slow on shipping parts.

 

[Jacob J.]

The ebay kits are Woodland International kits. They all come from the same source and manufacturer. There is no other source for BB kits.

 

[excess650]

Have you tried cleaning that bore with an SOS pad or Scotchbrite and dishwashing liquid? If it cleans up some, then try a quick "hone" with 220 wet/dry moving in/out at angles like a hone would. If its truly scored, you have nothing to lose. If its really something on the surface, you might still have a good cylinder. That chrome is HARD.

 

[parrisw]

What does the piston look like, it looks like you could save that cylinder.

 

[Martinm210]

The ebay kits are Woodland International kits. They all come from the same source and manufacturer. There is no other source for BB kits.

Ahh, I was wondering about that, I was hoping there was more than one though. Oh well, I'll just order one from Bailey's if this one is about done.

Have you tried cleaning that bore with an SOS pad or Scotchbrite and dishwashing liquid? If it cleans up some, then try a quick "hone" with 220 wet/dry moving in/out at angles like a hone would. If its truly scored, you have nothing to lose. If its really something on the surface, you might still have a good cylinder. That chrome is HARD.

Not yet, this was just a quick wash down with purple super clean. I think I've got most of the gunk off, it actually feels very clean, just fine fine lines.

What does the piston look like, it looks like you could save that cylinder.

I just cleaned up the piston and took these pictures. Cleaning reaveals that it is an OEM piston, it does show more damage on top of the piston now that the carbon is removed. The rings and skirts of the piston are however in not too bad of shape. It probably could be sanded and salvaged I suppose.

Hmmm...I guess it could probably salvage it, just not sure how long it would hold up.

 

[parrisw]

Hmm, looks like something went through that piston and cylinder.

 

[Martinm210]

So, I'm pretty sure I'll replace this P&C.

I'm going to go the 046 jug mod with it, may as well, it'll be entertaining increasing the displacement and cramming it into the smaller saw. I've got a small mill so slotting out the jug and shaving off fins or the base as needed shouldn't be to much trouble. Are the 046 aftermarket jugs also the same manufacturer?

As in, Is this kit:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=330300672634

The same as this:
http://www.baileysonline.com/itemdetail.asp?item=BBN 046&catID=258



Seems like I've heard about the NOS brand before. I may just buy a stock 046 jug new as well, haven't decided yet.

 

[Jacob J.]

They're the same. The standard size aftermarket 046 top ends are from a different manufacturer.

 

[Nitro-Fish]

Pick up a 220 grit AO flex hone (for the right cc's of course), give it a good coating of 30 weight oil, place it in a drill motor (around 700 to 900 rpm) and give that cylinder about 6 to 8 seconds in forward, switch over to reverse do the same; see what it looks like then, you're only out $25-$30 if it doesn't clean up, but I think it will surprise you.

 

[Martinm210]

Pick up a 220 grit AO flex hone (for the right cc's of course), give it a good coating of 30 weight oil, place it in a drill motor (around 700 to 900 rpm) and give that cylinder about 6 to 8 seconds in forward, switch over to reverse do the same; see what it looks like then, you're only out $25-$30 if it doesn't clean up, but I think it will surprise you.

Thanks, I've been trying a little emery pad, I'll check it out.

They're the same. The standard size aftermarket 046 top ends are from a different manufacturer.

Ok, I'll stick with Bailey's then
Thanks!
Martin

 

[Martinm210]

FYI,

After alot of back and forth I decided to order another woodlands kit from Bailey's.

Not having a shop press yet, I decided on buying another 044 case with decent bearing to fix the bottom end, so I figured I may as well spend a bit more on this project and have fun with it. I went ahead and ordered the 046BB kit, the mill was sitting so lonely in the garage anyhow...

There was just something about an 066 sized bore on my 044 build that I just couldn't resist..

 

[Jacob J.]

You bought a used 044 case with used bearings?

 

[Martinm210]

You bought a used 044 case with used bearings?

Yes, I'm guessing that's a bad idea?

The seller said the bearings were good (depends on his definition of good), this was one of those stripped down cases with nothing but the case and crank in it.

I need a shop press which I don't have yet. I did buy a flywheel puller and I could probably build the special tools and arbors for pressing, but I need a press bad.

Maybe I should have spent my money on this instead?
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=1666