piston instalation

backdraft341

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i have a lawn boy S21ESNA and im trying to figure out how to get the piston and rings back in the block. i dont want to buy a ring compressor for $50 for one job. does anyone have any tricks?
 

Fireman 123

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I've used a hose clamp before. It's a little tricky, but it worked.
 

Phototone

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The hose-clamp method works fine. Get everything all oily with something like STP, real slick. The excess lubricant will burn off, first time you start the engine.
 

Carscw

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Go to Home Depot in the plumbing there is a black sleeve with two hose clamps on it. It is made to rap around a pipe. It works just as good as a ring compressor.
 

Phototone

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Harbor Freight ring compressor $8.88.

The problem with ring compressors intended for automobiles, is that on F engine and later lawnboys, there is no head, the cylinder and head and 1/2 the crankcase are all one piece. You have to go in thru the crankcase, and if you want to keep the piston and rod attached to the crank, the only way to insert the piston into the cylinder is with a very small type of ring compressor. A hose clamp fits the bill quite nicely, in absence of lawnboys discontinued ring compressor tool. Once the piston is slid in far enough to capture the rings, you can unscrew the hose clamp completely and remove it easily.
 

reynoldston

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The problem with ring compressors intended for automobiles, is that on F engine and later lawnboys, there is no head, the cylinder and head and 1/2 the crankcase are all one piece. You have to go in thru the crankcase, and if you want to keep the piston and rod attached to the crank, the only way to insert the piston into the cylinder is with a very small type of ring compressor. A hose clamp fits the bill quite nicely, in absence of lawnboys discontinued ring compressor tool. Once the piston is slid in far enough to capture the rings, you can unscrew the hose clamp completely and remove it easily.

Yes I have been there and did that used a screw clamp as a ring compressor. And yes a good Snap-On ring compressor you will be looking at over 50 dollars which I have and use. I just happen to see the harbor freight ring compressor which it looks if you put rings in a eight cylinder engine when you are done with it its junk. Yes a lot of the smaller engines you install the cylinder assembly bottom down over the piston.
 

impalass

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i have a lawn boy S21ESNA and im trying to figure out how to get the piston and rings back in the block. i dont want to buy a ring compressor for $50 for one job. does anyone have any tricks?
I use a hose clamp. CAUTION DO NOT PUSH THE PISTON TO FAR FOREWARD AS THE BORE HAS A RECESS AT THE TOP AND THE RING WILL EXPAND INTO THAT RECESS AND GAME OVER. Connect the rod to the crankshaft then move the piston foreward.
 
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