Small Engines (Lawn Mowers, etc.): JD 445 motor problem, kawasaki model, head gaskets

Question
Hi, I have a 1997 JD 445 with a 22hp efi kawaski engine that has new pistons, rings, and rods due to a oil pump gear malfunction. Today I stated it and moved it into my garage to adjust the valve clearance which the Deere dealer told me to set at .010.(because I thought it was ticking)  I did the adjustment and it would not start or fire at all. I then double checked the clearance again and tried again. No luck. (prior to me messing with it ,it always started with no problems and seamed to have decent power)  Then i preceded to weld a whole in the muffler and when I started welding on the muffler it sounded like the engine back fired. So my question is, do you think I had it flooded with the valves not properly adjusted andwhen I welded on the muffler, could the back fire have ruined my rings or head gaskets? I did a compression check and read only 75 on one side and 50 on the other.  I do know the compression would have to have been considerably higher before I messed withit because it always started and ran fine aside from the ticking which i thought were the valves.  i think I should just leave stuff alone!

Answer
Hello Brad:

Have you Checked for Fire at the Plugs Since you did the Welding? If this Engine is a Kawasaki Model FD440V, FD501V, FD590V or FD611V, then the Valve Clearance is Set at .010in.. Make Sure you Set the Cylinder that you are Setting the Valves on to TDC on the Compression Stroke. THE CYLINDER MUST BE ON COMPRESSION STROKE OR THE VALVE CLEARANCE WILL BE WRONG. It is Highly Possible that the Head Gaskets or even the Rings May be Damaged. The Backfire when you were Welding the Muffler Indicates there was a Flooded Cylinder. There May be a Slight Ticking from the Valves in this Engine. This Engine has Solid Tappets and these Tend to be Slightly Noisy at Times. You can View a Breakdown/IPL of the Engine and Mower at this Site Addy, http://jdpc.deere.com/jdpc/servlet/com.deere.u90490.partscatalog.view.servlets.H... and Enter the Model Numbers (445) and Click Find. The Select the Lawn Mower File. Then Select the Sectional File. Then Select the Section of the Mower you Wish to View Online. I Suggest you Make Sure the Valve Clearance is Correct before Going any Further. If you Correctly Set the Valve Clearance, then Check the Head Gaskets. If you Hit a Snag or this Does Not Correct the Problem,  I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.

Good Luck

Respectfully

John

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Respectfully

John