New member new saw

[bmp01]

As per previous comments,  if you don't fix the route cause its going to happen again.  It would seem you never quite got the saw fixed in the first round of repairs so you'll be looking to dig a bit deeper this time. Air leak is favourite,  so make sure you pressure test the repaired saw or get someone to do it. 

 

Only useful thing to add,  if the original cylinder isn't trashed too bad it can probably be brought back to life by removing the aluminium deposits. Takes time but if you end up with a good, genuine used cylinder I'd take that over a replacement one. ... do a bit of research on here for 'how to....'

 

It's a good saw,  worth the effort. 

Edited November 3, 2017 by bmp01
Typos

[peatff]

2 hours ago, bmp01 said:

if the original cylinder isn't trashed too bad it can probably be brought back to life by removing the aluminium deposits. Takes time but if you end up with a good, genuine used cylinder I'd take that over a replacement one.

I did that with my 044 and replaced the piston with an ebay bargain, my thinking was if it doesn't work I'd get a Meteor piston and cylinder but it was fine. I used patio cleaner/brick acid to dissolve the aluminium transfer and rubbed it out with 240 grit and oil. There was one small pit in the Nikasil below the exhaust port not in a critical area and it's a good saw again now. It's worth spending a bit of time and money to get one running again and it gives you a warm glow when it works.

Edited November 3, 2017 by peatff

[bmp01]

22 minutes ago, peatff said:

I did that with my 044 and replaced the piston with an ebay bargain, my thinking was if it doesn't work I'd get a Meteor piston and cylinder but it was fine. I used patio cleaner/brick acid to dissolve the aluminium transfer and rubbed it out with 240 grit and oil. There was one small pit in the Nikasil below the exhaust port not in a critical area and it's a good saw again now. It's worth spending a bit of time and money to get one running again and it gives you a warm glow when it works.

All aftermarket pistons are cheap really, even decent Meteor brand. Time and effort to clean up a genuine cylinder etc, 10 pound cheapie or a 25 pound Meteor piston....... I don't feel the need to experiment with cheap 

 

 

 

[pinhead]

Thanks for the responses

To answer a few questions 

No I dont think I got it right the first time better yes but was never truly happy 

I think I am not bad at chain sharpening and I keep up with it usually just tidy it up every couple of tanks of fuel 

I am not scared of engine work and will go as far as I need I am just not that familiar with small 2 strokes 

I am a hotroder so tuning and engine building is enjoyable to me but I am more used to big v8s 

The reason for failure I am not truly sure may be an air leak or maybe I tuned it lean to try get it to work 

How do I test the crankcase for leaks or should I just change the seals out anyhow

[billpierce]

How has it failed? Is the piston scored? Or just low compression?

Ideally you would vac/pressure test it ( Google it, I use a mityvac) and this will tell you if you have a air leak in or around crank case.

[pinhead]

It lost all power pretty quick and sounded rough all I have done so far is pop the exhaust off and look at the piston and its scored 

I put the saw away for a few months as I have been busy but should have some time to sort it now that'

[pinhead]

Thats why I am now asking questions I like to be prepared and do the job right 

 

 

In my car I have done quite a bit of engine work I spent 2 years collecting parts as they came up used or in sales etc and then did the upgrade over a few weekends in the garage 

I had a clear plan of what I wanted to do and what parts I needed and because of that it was an easy job that has delivered the performance I was after and more 

I am just trying to do the same with the saw but parts should be much easier to gather together 

[spudulike]

I once had a 346 in with three cylinders, all shot. The owner had put on new cylinder after new cylinder and trashing them without realising the big end was on the way out and spitting out random bits of bearing cage.

I got there in a short time and stopped the repeated waste of money and there is the lesson!

As others have said, you will need to pressure/vacuum check the saw and make sure the saw carb is tuned correctly. you could just change all the seals and lines but I have seen a certain MS660 that had fractures to the crankcase causing air leaks. I did manage to seal it and port it and it is still running 3 years later so sometimes not actually doing the test can miss issues.

A lot of these aftermarket kits are a bit iffy and tend to have poor compression and this will lead to a boggy saw....I would personally always use OEM or Meteor.

[billpierce]

http://

He has some other good vids.

If you cannot bare a vac test then you could stick a decent meteor piston in, clean your cylinder adjust yer carb( if go 1.25 turns out to be safe) and tune up (many guides available) see how it performs. Airleaks usually are indicates by irractic idle and keep an eye on spark plug colour......def best to do a vac pressure test to eliminate this possible fault though or you could be back to square 1.

Good luck

[bmp01]

1 hour ago, pinhead said:

It lost all power pretty quick and sounded rough all I have done so far is pop the exhaust off and look at the piston and its scored 

I put the saw away for a few months as I have been busy but should have some time to sort it now that'

I would be tempted to pressure test the saw before you pull it apart, nothing to lose and maybe learn something useful.