Compression issue after rebuild

StarTech

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Here is the problem. First old crankshaft still has the aluminum transfer on the rod journal which will only destroy the new rod.

Second you have now ordered the wrong crankshaft for your engine as they must be ordered per the date code. Briggs changed them and the flywheel back in 2012. Now that you have a the newer crankshaft you will also new the new flywheel and the longer key. You will also that the flywheel timing is now differently keyed. The reason for the change was that the flywheel key was shearing and destroying the flywheel due the way it was aligned in the keyway. This all explained in the APSI 89 issued by Briggs to the dealers.

The only solution now is to either return the incorrect crankshaft (if they will accept it back) and get the correct one or order a new flywheel and key the that is match to the new crankshaft.

Originally all you had to do is use some Muriatic Acid and cleaned the rod journal and lubed.

Now you can see why having all the engine's info is important as changes are made along the way.
 

Emsguy

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Here is the problem. First old crankshaft still has the aluminum transfer on the rod journal which will only destroy the new rod.

Second you have now ordered the wrong crankshaft for your engine as they must be ordered per the date code. Briggs changed them and the flywheel back in 2012. Now that you have a the newer crankshaft you will also new the new flywheel and the longer key. You will also that the flywheel timing is now differently keyed. The reason for the change was that the flywheel key was shearing and destroying the flywheel due the way it was aligned in the keyway. This all explained in the APSI 89 issued by Briggs to the dealers.

The only solution now is to either return the incorrect crankshaft (if they will accept it back) and get the correct one or order a new flywheel and key the that is match to the new crankshaft.

Originally all you had to do is use some Muriatic Acid and cleaned the rod journal and lubed.

Now you can see why having all the engine's info is important as changes are made along the way.
This is how an amateur learns from his mistakes. There was no saving the Rod journal. What’s not shown in the picture is on the other side of the journal is a huge chunk that was taken out during the blow out.
 

StarTech

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This is how an amateur learns from his mistakes. There was no saving the Rod journal. What’s not shown in the picture is on the other side of the journal is a huge chunk that was taken out during the blow out.
See that why we images that covers all the damage but I have yet to see a crankshaft steel to be missing a chuck out the rod journal out of nearly 100 crankshaft rod failures. But I even hate to see amateur make these mistakes as it is costly at times.

Personally I don't have very deep pockets so I have to do my research before committing to things.
 
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