New guy here, 13 1/2 hp B&S no compression

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Dryan

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Need to get the tractor going for this summer, I did a leak down on the eng and air is coming out the exhaust muffler (both valves closed) so i guess the first thing to do is pull the head and take a look at the valve seats. I have a piston and a ring set for this engine also, My question is do i have to remove the eng from the tractor to gain access to install the piston?20170221_145441.jpg20170221_145441.jpg
 
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ILENGINE

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You will have to remove the belts, engine pulley, and the four mounting bolts alongs with the fuel line, control cables, and electric wires so you can remove the engine from the frame to get to the sump mounting bolts on the bottom of the engine. I wouldn't worry about removing the piston until I had the head off and could inspect the cylinder walls and find out why the exhaust valve is leaking. Maybe the exhaust valve seat came out, or something is holding the valve open.
 
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Dryan

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ILENGINE said:
You will have to remove the belts, engine pulley, and the four mounting bolts alongs with the fuel line, control cables, and electric wires so you can remove the engine from the frame to get to the sump mounting bolts on the bottom of the engine. I wouldn't worry about removing the piston until I had the head off and could inspect the cylinder walls and find out why the exhaust valve is leaking. Maybe the exhaust valve seat came out, or something is holding the valve open.
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Will make that todays project while its still warm out, let ya know what i see. Thanks for letting me know there is no access to the rod without removing from tractor.
 
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Dryan

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I got the head off today, the gasket did not appear blown but close to it, i could see some black carbon under part of the gasket, also see some scratch marks in the head where son in law removed removed a gasket a few years ago, the ex valve was not stuck, but from the looks might not have been seating correctly. I got the eng out and it up on the work bench. The cyc walls are smooth can not hang a nail anywhere.20170222_102226.jpg20170222_102813.jpg20170222_103844.jpg
 
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ILENGINE

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The head gasket will blow between the cylinder walls and the recess area for the push rod cavity. Any carbon trail in that area is a blown head gasket, in your case hadn't burnt through yet. Also it looks like the crosshatching pattern is gone from the cylinder walls, If the picture is accurate than you have a far amount of cylinder wear.
 
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Dryan

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ILENGINE said:
The head gasket will blow between the cylinder walls and the recess area for the push rod cavity. Any carbon trail in that area is a blown head gasket, in your case hadn't burnt through yet. Also it looks like the crosshatching pattern is gone from the cylinder walls, If the picture is accurate than you have a far amount of cylinder wear.
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This is where i become lost, what do i need to do about this condition? Do I remove the piston, then the rings, and measure the ring gap by inserting them in the existing bore? Son in law gave me a piston and ring set B&S #797009, the existing piston has a number on it 215624 STD an another number at the top 0.39.

Did some checking around this morning to find someone to clean the bore up or bore it. Two machine shops wont do it, now what?
 
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ILENGINE

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At a minimum you will need to remove the piston and break the glaze on the cylinder walls with a ball hone or another type of hone to reseat the new rings. Being able to tell how much wear you have requires special measuring tools. Finding shops to bore cylinders are getting hard to find.
 
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Dryan

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ILENGINE said:
At a minimum you will need to remove the piston and break the glaze on the cylinder walls with a ball hone or another type of hone to reseat the new rings. Being able to tell how much wear you have requires special measuring tools. Finding shops to bore cylinders are getting hard to find.
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I do have a measuring tool, i think im using it right, I placed it at the center of piston sitting level, only at 1 location in the bore. I don't know what the original20170223_154439.jpg bore size is are where to look.
I do have access to the ball hone you mentioned.

I guess my next step is to remove the bottom of the case to gain access to the rod and remove it. Thanks for your input.20170223_154332.jpg

What the son in law told me was the complaint was that oil was coming out of the breather hose going to the air filter after about 10 minutes of running.
 
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ILENGINE

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I can look up the bore size if you give me the model, type and code from the engine.
 
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Dryan

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ILENGINE said:
I can look up the bore size if you give me the model, type and code from the engine.
Click to expand...

model 21B707 type 0453 E1 code 06031ZA

update: I got piston out the 2 top rings are broke and came out in pieces. The cyc wall still looks ok.20170223_164648.jpg20170223_164658.jpg

I can also move the piston back and forth on the piston pin, I don't think that's suppose to happen.
 
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