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SX-F 250 2011 Engine won't start after tranny repair

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The bike just ran fine when my buddy found plenty of metal flakes during an oil change. So he took the engine apart and sure enough the outer bearing on the primary drive shaft broke.

Changed the bearing, oil pump, some other parts that didn't look so well and cleaned everything nicely. Most of the flakes were collected by the magnet in the oil drain plug, so there was no visible damage to the cylinder or piston. 

Put everything back together and since he was at all this, he decided to clean the Injector aswell and shim the valves to the specs.

But now the bike just won't start. Remember, the engine itself ran fine and he only splitted it because of the tranny noises.

It has a good, strong spark. The spark plug gets wet, so there must be fuel running through and the timing marks were checked at least 3 times by locking the crankshaft with the allen bolt and looking for the marks on the cam shafts standing next together.

But there are some strange things:

- the bike has an e-starter but it can't turn the engine

- turning the engine by hand goes slightly harder than before

- and you can't turn the engine backwards by hand

- if you remove the stator cover, the engine turns easier and even turns backwards

- but there aren't any grinding marks anywhere in the cover or on the stator. So we're pretty sure there's nothing touching

 

tried to bump start and tried using starting spray. Wires are connected correctly. Fresh fuel, new spark plug. 

Will test compression next before tearing it down again

Any other ideas ?

 

 

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did he linned up the cranksprocket (1 dot) with the intemidiat sprocket (2 dots) . if he didnt. the camtimming can be a little off.

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did he linned up the cranksprocket (1 dot) with the intemidiat sprocket (2 dots) . if he didnt. the camtimming can be a little off.

 

Yup, he did.

Turns out that the intake camshaft had some pitting marks and didn't rotate free. Maybe he didn't align the shafts to the head correctly so that they stuck. He grinded and polished the parts and now the engine starts up.

But has to keep an eye on it and will sooner or later change it.

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