Blown motor with 1.5 hours from rebuild...

[daveyboy440]

Ok sorry guys about this but a few months ago i had a 440 ex that somehow the timing chain snapped and the guides/tensioner got chewn up real bad, fixed it all up and BAM same exact thing again? any ideas? (it does have a very aggressive cam in it aswell)

[vze2hnvz]

What cam chain were you using, stock or heavy duty?

[daveyboy440]

stock, the heavy duty doesnt look like it would fit on the tensioner/guides.the 'lil lip on both sides make the oe chain fit snug enuff.

[44oEX]

your gears might be bad, I had the wildest WEB cam in my EX and never had any problem...you can use a 02 CRF timmign chain, same as heavy duty, but way cheaper...it's wider, but don't worry about the guide. they will wear to the size of the new chain.

[daveyboy440]

sounds like a plan, i just dont get why it was fine since i bought it and then all of a sudden this...i had put about 80 hours on it, and smooth sailing.

[cals400ex]

was the case bored out a little bit to give the larger 440 sleeve enough room to expand?

[F-16Guy]

Replace the tensioner and inspect the guides for proper installation. Make sure the new tensioner is fully retracted during installation, and then release the tensioner once fully installed.