New cylinder for ms461, do I need to replace gasket?

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Gu_42

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Im putting a meteor piston and cylinder on my 461 after straight gasing the original.

Do I need to replace the gasket between the cylinder and the bottom end?

Is there anything else I should replace or check while I have it apart?

I've also seen people mention they do a pressure test after rebuilding there saw, is this necessary? If so how do I do it?
 
I did this not long ago (well meteor piston and cleaned up the oem cylinder), and reused the gasket. I have not had a problem yet and the saw runs great. I had this same question and the responses I found said if it isnt torn up then it should be ok to reuse it.

As far as other things to change, just check out your wrist pin bearing to make sure it didnt get too hot. Mine was ok so I didnt replace it. You may want to just to be safe.

As far as pressure testing, there are several videos and other threads about that on this site, you will just need to search "Pressure testing crankcase" and will find lots of good info.
 
It is a good idea to vacuum and pressure test so you know there are no leaks. Of course you don't have to... but if there is a leak it may not last long. I found a crank seal leak on a saw I rebuilt recently and then replaced the seal and it was ok.

I have reused the gasket with a very thin layer of Threebond 1211 on each side. If it looks pretty fresh you should be ok without. The vacuum test will confirm.

I would rinse out the bottom end with premix and make sure there is no debris down there from when it was straight gassed. Not likely, but won't take long to check.

If the original cylinder can be cleaned up you may be better with a meteor piston and the OEM cylinder as Freudianfloyd did.
 
The cylinder is finished I think, I tried cleaning it up.
 

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I should have the new cylender today, hopefully it looks ok when it gets here. Ive read there are some good ones and bad ones from meteor
 
The cylinder is finished I think, I tried cleaning it up.
Most of what is in those pictures looks like there is still transfer from the piston on it to me, but it's hard to tell from pictures. That spot above the port though looks odd. Is that a hole or big chip in the plating?
 
Most of what is in those pictures looks like there is still transfer from the piston on it. That spot above the port though looks odd. Is that a hole or big chip in the plating?

If it's just a dirty spot, I would try using a hone with plenty of oil and see how well it cleans up. You may be surprised. I thought mine was toast too, but I was convinced to keep working on it, and it made it look like new.

Of course if your plan is to use the meteor cylinder then that works too. Make sure you take good pictures of the new cylinder, I'm curious what the meteor cylinders look like.
 
It looked like it was scratched through the plating to me but floyd you might be right. Can you tell with your nail if the remaining vertical lines are a groove or proud? Keep sanding?
 
It feels like there grooves to me, but I may be wrong. Up the top I think its a big chip out of the plating, thats the main reason I gave up.

I might try and hone it to see what happens, nothing to lose now
 
Is there a the reason for that? Or is it just cause most people dont have a new gasket available?
 
Most people remove it because the stock squish band with gasket is usually 0.040" to 0.060". Ideal range is 0.020-0.025" and the gaskets are usually around 0.020" ?

The reason to remove it is that the 0.025" squish band helps push the combustion gases to the center of the combustion chamber for a more complete burn which means more power.

I think it also advances the port timing a bit but I do not understand that well enough. Also a slight increase in compression.

I am yet to do the same on my saw. I need to find some soft solder to measure the squish band on top of the piston to confirm it is enough to remove the base gasket. I'm new to the mods myself but that's just what I have gathered so far from reading.
 
Heres some pictures of the meteor cylinder
 

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What do you think? Some of it looks better than the original to me, the stihl cylinder has more burs around the ports
 

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Im putting a meteor piston and cylinder on my 461 after straight gasing the original.

Do I need to replace the gasket between the cylinder and the bottom end?

Is there anything else I should replace or check while I have it apart?

I've also seen people mention they do a pressure test after rebuilding there saw, is this necessary? If so how do I do it?
We have a chainsaw thread to post all questions on.
 

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