B&S seized 5.0 on push mower
- Thread starter Safehorses
- Start date
I thought I'd share my 2 cents. If the cylinder and rings were not the issue, and it was the rod freezing up on the crank, I'd offer the following caution (that comes from experience). My experience with this is you can free it up and think all is good but beware! Every engine I've repaired with a frozen rod has left aluminum deposition on the crank due to the excessive heat which caused the problem in the first place. This does not go away on its own when you free up the rod/crank and should be removed by whatever means you choose, i.e. polish, acid, combo etc. and the rod replaced for proper journal clearance. If you don't, and merely get the rod loose, even with proper oil levels, the irregular finish between the rod and crank will overheat again and it won't last.
I experienced this a year ago with a JD 105 lawn tractor running a 17.5 BS. As this engine design is prone to do, the head gasket blew and the customer was not watching oil levels and it froze up. With some prying on the flywheel with a bar, he was able to free it up. He changed the head gasket and changed the oil/filter and filled to proper level. Started and sounded fine. 35 minutes into his 1st cut, it grenaded with catastrophic failure. When I got it and did the autopsy, the piston, rings and cylinder wall were just fine. This time the rod came apart at the crank journal and a whole bunch of ugly took place. I put a brand new engine in it!
Do you guys agree that the frozen rod repair should include polishing the crank and replacing the rod?
Good luck ... just one old-timers thoughts!
I experienced this a year ago with a JD 105 lawn tractor running a 17.5 BS. As this engine design is prone to do, the head gasket blew and the customer was not watching oil levels and it froze up. With some prying on the flywheel with a bar, he was able to free it up. He changed the head gasket and changed the oil/filter and filled to proper level. Started and sounded fine. 35 minutes into his 1st cut, it grenaded with catastrophic failure. When I got it and did the autopsy, the piston, rings and cylinder wall were just fine. This time the rod came apart at the crank journal and a whole bunch of ugly took place. I put a brand new engine in it!
Do you guys agree that the frozen rod repair should include polishing the crank and replacing the rod?
Good luck ... just one old-timers thoughts!
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When you have aluminum transfer the steel crank you should use Muriatic Acid to remove the aluminum transfer and replace the connecting rod(s).
Note Muriatic Acid is dangerous and should only be used outdoors, then neutralize after use, and the steel oiled to prevent flash rusting. Muriatic Acid can take your breath away so always be up wind of it.
Note Muriatic Acid is dangerous and should only be used outdoors, then neutralize after use, and the steel oiled to prevent flash rusting. Muriatic Acid can take your breath away so always be up wind of it.
Safehorses
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I put a new spark plug in it. Added fresh gas. After 5 pulls it started. Thank you all so very much! I now have a working mower. I'm so excited
Alan46
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