How to align up MS440 saw cylinder to 66cc bottom end?

francisjohn

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I'm in the middle of an MS440 build and it's my first hybrid build. I'm scratching my head at the best way of lining up the cylinder holes to the bottom end. I was unsure if anyone had any tips or tricks for this? Reason I ask is because it has to be absolutely spot on perfect. The width of the intake port, and where the piston pin is for the rings, if you move 1mm to the left, your ring is expanding in the intake port.

I'm trying to develop a spot on way. Any one who has made MS builds, I would appreciate any help.

Just a note, I do not have a 3D printer to print one.
 
Ive seen guys 3D print spacers that center it. However alot of people don't have access to 3d printers
Unfortunately I don't have access to a 3D printer. There is a local library but there is a 45-60 day wait list because little kids keep going there to print owls n s**t. Even if I did have access, I have zero knowledge in CAD, let alone creating a CAD file etc.
 
Unfortunately I don't have access to a 3D printer. There is a local library but there is a 45-60 day wait list because little kids keep going there to print owls n s**t. Even if I did have access, I have zero knowledge in CAD, let alone creating a CAD file etc.
Ive been using TinkerCAD. It is very user friendly. My Dad has a 3d printer. I might be able to print something for you if he's OK with it. I'll ask hime and let you know.
 
Without seeing your I'm only speculating here. I understand the issue. How difficult would it be to remove the pin and relocate it in the groove in a different location.

When building H.P. automotive engines in our shop we always located the top ring gap on the thrust side of the piston. Maybe there's something I don't realize about 2 strokers.
 
Without seeing your I'm only speculating here. I understand the issue. How difficult would it be to remove the pin and relocate it in the groove in a different location.

When building H.P. automotive engines in our shop we always located the top ring gap on the thrust side of the piston. Maybe there's something I don't realize about 2 strokers.
There is a pin that keeps the rings from rotating in these 2 strokes. If the ends of the rings are in a port it will snag the port and destroy the top end. The pins can't be relocated to the exaust side because the aluminum will expand faster than the steel pins and cause the pin to come out. The pin will then destroy the top end.
 
OK, I understand. Think about it. How was the pin put into the piston in the first place. They probably heated or cooled the piston and pressed it in. You should be able to get it out, even if you have to use this process. Drill a new hole and relocate the pin.

If you're really concerned practice on a junk piston. I bet someone here will give you one if need be. Also, if you are concerned with expansion of dissimular metals consider making an aluminum pin. There is no real pressure on it. Just keeps the ring from rotating. I really think this is doable, so give it a try.

I can't imagine what shape a 3D part would be that would work. Let alone, the fact it's exposed to the combustion temperature.
 
I'm in the middle of an MS440 build and it's my first hybrid build. I'm scratching my head at the best way of lining up the cylinder holes to the bottom end. I was unsure if anyone had any tips or tricks for this? Reason I ask is because it has to be absolutely spot on perfect. The width of the intake port, and where the piston pin is for the rings, if you move 1mm to the left, your ring is expanding in the intake port.

I'm trying to develop a spot on way. Any one who has made MS builds, I would appreciate any help.

Just a note, I do not have a 3D printer to print one.
This Is a dumb idea but could you use like a metal tape to tape around a piston till you get it lined up in the bottom part of the case and then put the cylinder ontop use sharpy and punch it in the middle
 
Ive been using TinkerCAD. It is very user friendly. My Dad has a 3d printer. I might be able to print something for you if he's OK with it. I'll ask hime and let you know.
Thanks man, I'll look into TinkerCAD myself. I mine as well start learning.
Without seeing your I'm only speculating here. I understand the issue. How difficult would it be to remove the pin and relocate it in the groove in a different location.

When building H.P. automotive engines in our shop we always located the top ring gap on the thrust side of the piston. Maybe there's something I don't realize about 2 strokers.
I actually thought if there was a way, however it's within the casting where the groove is, and whatever they fill it in to actually make the pin.
OK, I understand. Think about it. How was the pin put into the piston in the first place. They probably heated or cooled the piston and pressed it in. You should be able to get it out, even if you have to use this process. Drill a new hole and relocate the pin.

If you're really concerned practice on a junk piston. I bet someone here will give you one if need be. Also, if you are concerned with expansion of dissimular metals consider making an aluminum pin. There is no real pressure on it. Just keeps the ring from rotating. I really think this is doable, so give it a try.

I can't imagine what shape a 3D part would be that would work. Let alone, the fact it's exposed to the combustion temperature.
I appreciate the help, but I don't know if there is the most realistic/practical approach. If it comes down to it, I'll start getting creative.
This Is a dumb idea but could you use like a metal tape to tape around a piston till you get it lined up in the bottom part of the case and then put the cylinder ontop use sharpy and punch it in the middle
I read someone else about taping the piston to align it, which doesn't make much sense to me, because you can still turn the cylinder.

OH MY GOD IT JUST CLICKED. THE LIGHTBULB WENT OFF IN MY HEAD.
 
Thanks man, I'll look into TinkerCAD myself. I mine as well start learning.

I actually thought if there was a way, however it's within the casting where the groove is, and whatever they fill it in to actually make the pin.

I appreciate the help, but I don't know if there is the most realistic/practical approach. If it comes down to it, I'll start getting creative.

I read someone else about taping the piston to align it, which doesn't make much sense to me, because you can still turn the cylinder.

OH MY GOD IT JUST CLICKED. THE LIGHTBULB WENT OFF IN MY HEAD.
Sorry if I didn’t describe what I meant very well but I am just thinking why not center the piston and then use the piston to get the alignment
 
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