Big bore 460 fubar

[Patrick62]

I am glad I was working on a project saw. Took it apart, cleaned it up, and decided to try the big bore kit. Install went well, used the good clips. Went to start it, and I knew something wasn't right. After much fuss, I actually got it to run for little spurts. Peeped into the exhaust port and looked at the nice deep gouges. Oh :censored: .

Fine and dandy! It is only a disaster! Swap the stock jug and piston back on! I had to press the piston out with a screwdriver down the spark plut hole, and then force the jug off with pry bars against the case!!!

What was then before my eyes was amazing. I will post pix tomorrow. Camera is charging up. Clips did not come off. Instead the piston and cylinder got real cozy. After reading 1953greg's thread down there I realized where things went wrong. The edges of the ports are squared off. I needed to get in there and round them all off. Just a little late now.

So after I washed out all the shrapnel from the crank, and cleaned everything up again I re-installed the stock 046 stuff. Fired right up.

So now I have a real nice gouged piston with a broken skirt for a decoration, and a gouged out cylinder for a paper weight.

-Pat

 

[fishhuntcutwood]

From Bailey's? I'd talk to Greg.

 

[1953greg]

Patrick,
whats the visual difference in the good clips and the poor ones. the ones that came w/ this kit were in a red transparency slip. they were not simple c shaped like the oem clips. the tip of the c clip extended inward so one can squeeze the tips together. easier to install than the oem but maybe only 2/3 as much tension.

as for the cylinder, the edges of the ports were really sharp. they need a radius edge. i spent a total of bout 3 hours w/ die grinder, cordless drill w/ 180 grit emery cloth rolled to a point and wrapped on a screw bit. then finished w/ the crocus cloth w/ my fingers. this was my first one but i have a friend who is tool maker. he kept me n line along w/ this site.

hang n there dont give up maybe baileys wil give u a discount on a replacement.

good day 1953greg

 

[Patrick62]

different clips

I saw no big difference, I have both out there. I used the ones that were sent to me as the ones in the kit were supposed to be "bad". Yes there is less tension than the origional ones, and WAY easier to install (and remove). I still don't understand how a clip could come loose anyway, I mean what does it gotta do

Anyway, I did get the kit crom Baileys. Not sure what Greg could do for me, but one thing I know for sure. I ain't doing this again. My saws (both of 'em) are going to stay stock. It would have been interesting to see if 5 cubes would be better. However the project saw is showing it's age, and sticking the BB kit might have been pushing it a bit.

-Pat

 

[Patrick62]

Pix of the remains

notice the cracked skirt.

And here as well.

Cylinder ain't looking too good.

Total running time of maybe a minute. Total time of trying to start it, maybe 20 minutes.

-Pat

 

[Mike mandry]

Ouch, that had to hurt.

Hope you get things worked out.

 

[HiOctane]

Does both clips were still there after you reopened the engine?Looks like something was inhaled by intake.Did you found something unusual in the case?

 

[superman_36]

bailey's would probably replace the kit for you. I would contact them

 

[JimL]

Looks like something was dropped down the carb/intake or got left in the carb or intake when it was assmebled..

 

[Freakingstang]

That could have resulted in the wrong port lip angle inside the cylinder. Something that many don't know, but when you port a cylinder, you have to test fit the piston without rings and it should "plop" to the bottom. If there is any high spots for the porting or in this case the casting, it will show a high spot on the piston and keep the piston hung up a little when it drops. i would have thought that baileys would have had this worked out before you received it.


Steve

 

[rahtreelimbs]

I am sure that Bailey's will make good on the top end. Just hope that the "schapnel" didn't cost the lower-end!

 

[Husky nut]

sure dont look like a wrist pin clip falling out to me(normally tears chunks from the cylinder wall not small lines)...looks more like something foreign was left in the intake or in the block...

 

[Crofter]

Looks like both rings are intact and you say both circlips were in place so it sure looks like hardware disease. More likely from the crankcase rather than muffler since it would have to have gone down the transfers to get at the bottom of the piston skirt. Had to have been pretty hard material too. What did the original piston and jug die of?

 

[stihltech]

quality

After seeing those pics, I have doubts about cylinder quality. In all my repair time, I have never seen a piston scored that bad without a crank or other parts having come apart.

Take that one up with the seller. I would think they would want it back for diagnostic purposes.

 

[Patrick62]

I will try to explain...

There was no junk in the crank, engine was in operating order when swap was initiated. Nothing was lodged in intake, ya have to take all that apart to swap.

I will email Baileys directly, maybe something can be worked out.

I did re-innstall the origional jug and piston after cleaning out the bottom end with 1/2 can of brake cleaner. Engine then started easily, and runs as well as it did before. I have not cut anything with it, not sure of longevity.

Both circlips remained in position. It is more like what was mentioned, something didn't fit right. Right off the bat, like 6 pulls into starting it bounded up, and then the rope pulled thru the handle. Fixed that, and went after it again. and again, and eventually it ran for 15 seconds and then died.

Oh well :jawdrop:
-Pat

 

[tek9tim]

like 6 pulls into starting it bounded up, and then the rope pulled thru the handle.

Let's review: you yarded on it 5 times with no trouble. Then, on the 6th, it bound up. You then yarded on it so hard that the the rope pulled through the handle, then it eventually fired and died. Pulling 5 times with normal resistance suggests that whatever tore it up was not affecting it yet, but by the 6th it made its way to blocking everything up, then got overtaken by your force, and so on to complete failure.

I wonder why you yarded on it hard enough to pull the rope through the handle. My theory is that if an engine doesn't want to turn over, I don't force it, I'd rather tear it apart before I bust everything up.

 

[Lakeside53]

There was no junk in the crank, engine was in operating order when swap was initiated. Nothing was lodged in intake, ya have to take all that apart to swap.
-Pat

Are you sure you didn't drop one of the OLD circlips down into the crankcase when you took off the old piston? I count them (2!) on my work bench after dissasembly... Like a surgeon, it's real easy to loose a sponge or two...

Looking at your pictures, there was definitely something hard in the crankcase or cylinder... How is the crank now? Has the bottom end lost part of its bearing? What about the ball carriers on the mains? If you have screen on the muffler, the debris of whatever caused the problem will either be trapped in the muffler or still in the crankcase...

 

[Patrick62]

Yarded out, I like that.

It was hard to crank from the get go. Under normal conditions, it should have sputtered on a few pulls. It didn't. When the knot pulled thru the handle is probably when the piston got caught and cracked the skirt.

I did not lose any circlips in the bottom. I assembled the engine back to stock 046, and started it just fine. I stuck a bar on it tonight, and will lay it into a test log tomorrow before I have to run off to work for the week.

What I should have done is "ported" the jug and smoothed all the edges.
What I should have done is when it was hard to crank on the first four pulls, then yanked it all apart. I assembled it with a liberal amount of lube, makes it easier to slide the rings in.

Muffler had a scattering of aluminum particles in it. That is when I knew something had gone terribly wrong. If you look at the pix a little you can see that 3 ports have gouges in them, but not the 4th. The intake, and both transfer ports. Exhaust isn't for some strange reason. A loose hunk of something would have not made 9 grooves in the intake followed by a equal number on the transfer ports.

What is "cranking speed" anyway on a stiff cylinder? I could not get it going as fast as my other saw. Would that be fast enough to move enough air to say float a hunk of metal into the cylinder? Lack of lube? It had the initial coating, and then honest to gosh 40:1 mix that runs just fine in the other 3 saws (I get real particular about mixing).

-Pat (cool smiley)

 

[bump_r]

Am I reading correctly that one must finish the machining on a Bailey's big bore kit? It does not come ready to assemble? I can see gapping rings and maybe cleaning assembly or shipping gunk off it, but a guy has to add 3 hours of his own time to complete the porting work? I'm not sure that sits well with me...

Adding port work to enhance the product to your individual preference or performance goals is cool, but just to make it usable? Yeah, this is a separate issue from the current logic of foreign (Chinese? heh heh) material ingestion, but it is a subject that was broached around which I'd like to wrap my head.

 

[Lakeside53]

Am I reading correctly that one must finish the machining on a Bailey's big bore kit? It does not come ready to assemble? I can see gapping rings and maybe cleaning assembly or shipping gunk off it, but a guy has to add 3 hours of his own time to complete the porting work? I'm not sure that sits well with me...

Adding port work to enhance the product to your individual preference or performance goals is cool, but just to make it usable? Yeah, this is a separate issue from the current logic of foreign (Chinese? heh heh) material ingestion, but it is a subject that was broached around which I'd like to wrap my head.

I agree... quality control really sucks, and Baileys (assuming this thread problem is really their fault) needs to learn from JET, Grizzly (... and almost everyone else), and just about all the ski and sports equipment manufactures - if you move your manufacturing to China, you move your QA people over there too.

I put TS400 "aftermarket" jug/piston on a cut-off saw, and it needed port work to remove the sharp edges - I just ball honed it again, lightly.. Shouldn't need too...

The Piston/cylinder sets from "Germany" on the EBAY right now are all from China...