Seeking oversize piston kit

[vamtjewboy]

I have a 3120XP with serious piston and jug damaged. While milling lumber it just died on me. I've taken it completely apart and found the piston and jug to have been seriously damaged by an unknown piece of metal. I have no idea where the metal came from but a friend speculates that a piece of the baffle inside the muffler broke off and was somehow sucked into the exhaust port. Regardless of how it happened, I'm more concerned with how to make it run again! The piston is completely F'ed. The jug however seems salvageable if I can bore it out a little.

My question to you guys is #1 where do you think the metal came from, and #2 where can I get an oversize piston kit?

Thank you in advance!
Nick in VA

 

[Teddy.Scout]

I know very little compared to most here! So only my 2 cents

The boring of a piston can? be done, but then you need to reline it!
Kinda costly.

And the oversize piston for that saw may need to be custom made unless there is one out there. I haven't seen one, but others may know of.

I would use the search, and check past threads for that.
You may be better of just soaking it up with a oem P/C.

How did the piston skirt look? and the rings?(could these have been the culprit)
Check the muffler for the missing pieces. I would try to find out what caused it before spending the big green backs.

 

[parrisw]

To make a long story short. NO, you need a new piston and cylinder. OEM, it will be expensive.

 

[SawTroll]

To make a long story short. NO, you need a new piston and cylinder. OEM, it will be expensive.

Boring out a damaged cylinder and replating it is not an option, even if you could find a suitable piston (but I believe that won't happen) - it will be much more costly than an OEM set anyway!

 

[SawTroll]

I know very little compared to most here! So only my 2 cents

The boring of a piston can? be done, but then you need to reline it!
Kinda costly.

And the oversize piston for that saw may need to be custom made unless there is one out there. I haven't seen one, but others may know of.

I would use the search, and check past threads for that.
You may be better of just soaking it up with a oem P/C.

How did the piston skirt look? and the rings?(could these have been the culprit)
Check the muffler for the missing pieces. I would try to find out what caused it before spending the big green backs.

Sorry - but what is boring a piston really about??????

 

[keith811]

Sorry - but what is boring a piston really about??????

:notrolls2:

 

[keith811]

one of the sites sponsors has what you need wont name names but it starts with a B

 

[SawTroll]

one of the sites sponsors has what you need wont name names but it starts with a B

Sounds familiar!

 

[keith811]

Sounds familiar!

it is very possible that I "borrowed" that line from someone on here:monkey:

 

[Teddy.Scout]

Sorry - but what is boring a piston really about??????

No need to say sorry! Cylinder! My bad!

 

[AUSSIE1]

http://www.baileysonline.com/itemdetail.asp?item=HVP+506+29+42+72&catID=1850

http://cgi.ebay.com.au/3120-XP-chai...emQQptZLH_DefaultDomain_0?hash=item439be3212e

 

[blsnelling]

I would not use aftermarket on a 3120.

 

[ran3465]

I just installed an aftermarket piston and cylinder on a 3120, the kit was purchased from baileys and the quality looked just fine. I think the problems with the aftermarket stuff is sporatic, Ive done a couple of the kits on different saws and they have all worked out just fine.

 

[timberwolf]

+1, I have seen BB and aftermarket jugs that range from basically unsalvagable to better than OEM. So its a bit of a crap-shoot, go low dollar and take a chance or spend the money and know you will bring the engine back to factory condition?

 

[rupedoggy]

Find out where the metal piece was originally. Possible culprits are:
Broken ring.
Wrist pin clip.
Small needle bearing or cage piece from the crank shaft bearings, wrist pin bearing, or big end rod bearing.
A small screw or other part from the carburetor.
Most of the time a close inspection of the damaged area will reveal the shape of the broken piece. Sometimes the piece itself will be embedded in the aluminum. If something is still wrong with the saw and you reassemble it without finding the cause, you may destroy all the replacement parts.

 

[mtngun]

I've had a piece of a cracked muffler sucked into the jug, so the OP's original explanation may be correct. But, in my case, it was obvious the muffler was falling apart, and there were slivers of metal rattling around in the muffler, too. Eeek !

 

[vamtjewboy]

oem vs aftermarket

man, i don't know what to do. that is a $200 difference! i'm not working now and $200 is a chunk of change these days. but the saw is my money maker (when i can find the work). does the golf come with a warranty? thanks to everyone who replied to my question!

one more question. would a screen between the head and the muffler restrict air flow too much? i'm pretty sure the piece came from the muffler. but i still have to take the carb apart to make sure nothing is missing there.

-nick

ps. my local saw show said "no way" on reboring due to the chrome lining. otherwise they said it was possible.

 

[Dan_IN_MN]

You "might" want to consider replacing the muffler too if it's falling apart. ??

 

[vamtjewboy]

muffler

i always drill out my mufflers. i think a drilled edge somehow got weak and broke off. but that's a good idea! if i drill out from now on i will put a screen between the head and muffler. thanks

 

[mtngun]

man, i don't know what to do. that is a $200 difference! i'm not working now and $200 is a chunk of change these days. but the saw is my money maker (when i can find the work). does the golf come with a warranty? thanks to everyone who replied to my question!

one more question. would a screen between the head and the muffler restrict air flow too much? i'm pretty sure the piece came from the muffler. but i still have to take the carb apart to make sure nothing is missing there.

I've never heard of anyone putting a screen on the exhaust port. Yes, it would restrict flow. Just give your muffler a good inspection, look for fatigue cracks -- mufflers don't last forever.

Don't know what to tell you about the top end. Most pro sawyers use OEM parts. But, I understand money is tight these days.