ms880 Rebuilding 2007 ms880

[pleasant]

That cylinder looks pretty bad from what I can make out in that pic.

 

If you are going to all that effort with an entire strip down and replacing all those parts at all that cost, and you are happy to fit an aftermarket piston, then I would invest in a new aftermarket cylinder while you're at it. Used 880's go for around the £800 mark, and with those, you don't know the history and may well end up with a pup that still needs money throwing at it- after all it is rare a professional user is happy to sell a good saw if there's nothing wrong with it. At least, you may well be spending near to £800 on this one, but afterwards you will know it's good to go.

 

Edited December 11, 2022 by pleasant

[openspaceman]

13 hours ago, gand said:

I can't see why you wouldn't save it if you can, the price of the new equivalent is at least £1500. If it was me I'd get it done 

Yes , he has committed now so get on with it and make a good job of it, I hope it split easily with nothing damaged.

 

On the few occasions I have split a saw I have always decided not to carry on but that one can hardly have any bottom end wear so a clean up,  new seals and gasket and it should be good to go.

[bmp01]

What's to decide ? OEM cylinder is best option, reuse the cylinder unless its clearly damaged beyond salvaging. The only way you'll know is by giving it a go but I'd guess that'll clean up. Many posts on here regardIng cylinder cleaning, best to do some searching....

 

Edit: lucky bu88er saving an 880 from the skip. 

Edited December 11, 2022 by bmp01

[TimberTickler]

2 hours ago, openspaceman said:

Yes , he has committed now so get on with it and make a good job of it, I hope it split easily with nothing damaged.

 

On the few occasions I have split a saw I have always decided not to carry on but that one can hardly have any bottom end wear so a clean up,  new seals and gasket and it should be good to go.

Yeah the crank case split easily, bought the proper tools for the job using the Stihl mounting tool, at a bloody expense but hopefully will come useful for future projects. 

 

[openspaceman]

1 minute ago, TimberTickler said:

Yeah the crank case split easily, bought the proper tools for the job using the Stihl mounting tool, at a bloody expense but hopefully will come useful for future projects. 

 

Top job then, let us know how it goes and good luck.

[spudulike]

OK....... I have done a few of these big bangers, loads of 660s, 395s etc and brought back many saws with similar cylinders and often worse.

The cylinder doesn't look too bad in my book...sorry chaps but that is my opinion based on experience and reusing the OEM cylinder is always best if it is possible...read on-

I would clean the bore up with a light abrading with 400 grit paper and then apply brake cleaner to degrease.

You then use caustic soda (Sodium Hydroxide), brick cleaner HCL or something similar. Any fluid that eats aluminium will do. Apply it and watch the streaks on the cylinder fizz. Once it stops, clean with a cloth, abrade and do the above again.

Once the bore is clean, I hone the bore with a three legged hone...just lightly, some use ball hones but they are relatively expensive.

Once this is done, run a diamond file around the exhaust port edge and lightly rub with a bit of wet and dry.....just to make a nice job.

After this, the bore should be smooth and you should not feel any high point with your fingertip. Visually, you should see where the hone has been but don't worry if it doesn't look perfect, those black marks are often difficult to remove completely.

Fit your new piston - get the direction right...arrow points to the exhaust port...Meteor....excellent choice.

Pressure and vac test - this is damn difficult with the sprung muffler seal if it is of this type but it can be done. Assemble the saw, tune the carb and keep reasonably under the max spec...1.0 - 1.5k is safe and gives the engine a fine chance. 

Use it hard but not for too long cuts. You want those rough surfaces to bed in quickly whilst they are rough but not generate too much heat. 

If you do this, you should end up with a top job and with minimal costs....that's why I was always so busy!!

I did have a 460 I rebuilt fail after 4 years....the owner dropped a tree on it.....made me smile....the rest are probably still out there working.

 

[TimberTickler]

8 minutes ago, spudulike said:

OK....... I have done a few of these big bangers, loads of 660s, 395s etc and brought back many saws with similar cylinders and often worse.

The cylinder doesn't look too bad in my book...sorry chaps but that is my opinion based on experience and reusing the OEM cylinder is always best if it is possible...read on-

I would clean the bore up with a light abrading with 400 grit paper and then apply brake cleaner to degrease.

You then use caustic soda (Sodium Hydroxide), brick cleaner HCL or something similar. Any fluid that eats aluminium will do. Apply it and watch the streaks on the cylinder fizz. Once it stops, clean with a cloth, abrade and do the above again.

Once the bore is clean, I hone the bore with a three legged hone...just lightly, some use ball hones but they are relatively expensive.

Once this is done, run a diamond file around the exhaust port edge and lightly rub with a bit of wet and dry.....just to make a nice job.

After this, the bore should be smooth and you should not feel any high point with your fingertip. Visually, you should see where the hone has been but don't worry if it doesn't look perfect, those black marks are often difficult to remove completely.

Fit your new piston - get the direction right...arrow points to the exhaust port...Meteor....excellent choice.

Pressure and vac test - this is damn difficult with the sprung muffler seal if it is of this type but it can be done. Assemble the saw, tune the carb and keep reasonably under the max spec...1.0 - 1.5k is safe and gives the engine a fine chance. 

Use it hard but not for too long cuts. You want those rough surfaces to bed in quickly whilst they are rough but not generate too much heat. 

If you do this, you should end up with a top job and with minimal costs....that's why I was always so busy!!

I did have a 460 I rebuilt fail after 4 years....the owner dropped a tree on it.....made me smile....the rest are probably still out there working.

 

Spud, that's great advice! I'd love to try and save the original cylinder, and avoid the £270 hit on and new cylinder and piston. I've already bought the piston which was hard to get, especially meteor, came from Greece. 

 

If you've saved many cylinders before, would you be able to assist with my one as it's sounds like I have one shot to get it right, get it fixed otherwise, the only option is the £270 route of a new cylinder and piston... 

 

Also, is there anyone local to Somerset who specialises in rebuilding saws, like yourself who could give me a hand with the project, I have found a contact up in Leeds who ports saws and rebuilds, and he said new piston and cylinder is the only route now.. 

 

[spudulike]

The only fella I know who is down near you.... Exeter is Gardenkit, he knows his onions but runs a business so may not have time to help you out.

I would just do as I have said. Lets face it, if you have split the cases then doing the rest should be relatively easy. Just ask questions on here and follow the info given.

I have used Leo in Greece for Meteor pistons, he is fine.

The Leeds fella...I know of him as he asked me to port cylinders for him but didn't much care his approach..... up to you who you want to listen to. 

If that saw was sitting on my bench, I would have got it going just as I have explained. It is a big pity it has had the ingress of grot in to the main bearings otherwise this would have been a really simple job.

The cylinder will be fine. What usually kills them is when you get scores running up and down the bore caused by busted rings or circlips or the plated surface being ripped off. Yours looks relatively lightly seized and getting rid of the transfer and breaking the glaze in the bore will give you a decent base for sorting it.

[TimberTickler]

27 minutes ago, spudulike said:

The only fella I know who is down near you.... Exeter is Gardenkit, he knows his onions but runs a business so may not have time to help you out.

I would just do as I have said. Lets face it, if you have split the cases then doing the rest should be relatively easy. Just ask questions on here and follow the info given.

I have used Leo in Greece for Meteor pistons, he is fine.

The Leeds fella...I know of him as he asked me to port cylinders for him but didn't much care his approach..... up to you who you want to listen to. 

If that saw was sitting on my bench, I would have got it going just as I have explained. It is a big pity it has had the ingress of grot in to the main bearings otherwise this would have been a really simple job.

The cylinder will be fine. What usually kills them is when you get scores running up and down the bore caused by busted rings or circlips or the plated surface being ripped off. Yours looks relatively lightly seized and getting rid of the transfer and breaking the glaze in the bore will give you a decent base for sorting it.

Cheers spud, the issue I have with going further doing the saw myself is removing and replacing the bearings as I have no special tool for removing and installing. Also would need to purchase the 2nd Stihl tool (£100+) to remove the crankshaft from the flywheel side. 

 

The bloke in Leeds has been very helpful with advice and said he can do the work, removing and installing the bearings but suggested cylinder is past repair and OEM new cylinder and piston is only route.

 

Sorry to rattle on, but just wanting advice as this is the first saw I'd be rebuilding, haha and it so happens to be the biggest! 

 

Definitely committed to getting it running tho. 

 

Cheers again for the advice! 👍

[peatff]

42 minutes ago, TimberTickler said:

The bloke in Leeds has been very helpful with advice and said he can do the work, removing and installing the bearings but suggested cylinder is past repair and OEM new cylinder and piston is only route.

 

It looks bad but it's probably all just aluminium transfer and it's below the port. My 044 was worse than that and cleaned up nicely and still works well. He probably doesn't salvage pots like us because he can pass the cost on to the customer and save himself a lot of time.