Engine locked up!

[irefin]

My engine finally locked up,kaput! It was progressively losing power and getting noisier right before she died.I got it apart this morning.The piston is chattered around the edge,bottom ring was broke in half but still in place.The needle bearing is intact at wrist pin.It appears the crank bearing is froze up tight.Cylinder looks to be salvageable,a little honing should fix that with a piston & rings it might come back.What is invloved in splitting the case to fix the crank-rod bearing?BTW I ordered a new engine yesterday so this will be a winter project rebuild. Thanks irefin

 

[GearNut]

The bearing itself is an oddball size. Most folks replace the whole engine and keep the blown engine for spare parts. The flywheel assembly requires a hydraulic shop press and a flywheel truing stand to rebuild, if you can actually find the bearings and have the parts to rebuild them.

Here is Norm's thread on splitting the crank cases: http://motorbicycling.com/showthread.php?t=391

Here is Al.Fisherman's: http://www.motoredbikes.com/showthread.php?23495-Breaking-down-a-China-HT-engine-PICTURES

 

[2door]

And, DO NOT hone the cylinder. These little engines have a very thin chrome plating on the walls. Honing will remove or damage the chrome and you'll be left with steel piston rings scraping aluminum.

Tom

 

[Bikeguy Joe]

And, DO NOT hone the cylinder. These little engines have a very thin chrome plating on the walls. Honing will remove or damage the chrome and you'll be left with steel piston rings scraping aluminum.

Tom

GREAT reminder Tom!