Replaced head, might have messed up timing By seanstr (Read 1,841 times)

[seanstr]

Getting head off, no problem, making sure timing chain is back on exactly like I found, hard. I think I messed that up. I need to check this. How do I re-time this engine gy6 150cc bashan eagle milano.

[Bashan]

Read over this thread and see if it answers your question. If not get back to us on this thread. Rich

[seanstr]

I don't know. I have to diff time to do this

[Alleyoop]

Just in case there is a next time Before taking the Cam and Chain off Mark the a tooth and and chain that way when you put it the chain back on you will not be off a tooth either way.
Alleyoop

[Kaveman]

Make sure your center hole on the cam is up and the 2 side holes are on each side of the head. If your missing the center hole when re-assembling with the timing chain , your cam is 180degrees wrong ! I did that on the Roketa I previously had and didn't get the engine to start till I realized my error thanks to the gang here on scoot doc !! One more quick note , you need to re-adjust your your valve's on both sides after your cam shaft is installed and head bolts tightened !!
will c. ;D

[seanstr]

Dec 19, 2011 14:42:31 GMT -6 seanstr said:

I don't know. I have to diff time to do this

It's timed right, what else could be done, wrong

[seanstr]

It logs like picture above

[jct842]

takes air/fuel, compression, and a spark at the right time. one or more of them are missing.

after checking for spark it might be a good idea to be sure your valves have some clearance like ,003 to .005 if you are close it will run. of course if you have a compression gauge thats easier to check than valve clearance, you want in neighborhood of 150lbs while cranking with the throttle open.

[seanstr]

It it ran before I changed head, changed head, won't run, it Won't even kind of run, I'll try to attach a video of it not running, trying to start, a picture of head

[sprocket]

You are a link or more out on the cam chain or it is not on the crank sprocket...the engine MUST be TDC by setting the piston when you reassemble the head and cam chain.. anything else and it won't run...

Have you checked the compression? spark? fuel flow?

[seanstr]

T mark position

Attachments:

[seanstr]

Holes st lined up correctly

Attachments:

[Alleyoop]

Did you ground the engine to the Frame maybe you forgot to reattach the ground wire to the motor from the frame and you will not get Spark.
Alleyoop

[sprocket]

>>T mark position

Crappola

Never use the 'T' mark they are way out...and 98% of cam chain problems are because people use it for TDC.

It IS NOT TDC it is the firing point of the CDI about 10 degrees advanced... enough to be off a link on the cam chain...

The ONLY WAY TO GET THIS RIGHT is to pull the head and set the piston to EXACTLY TDC then redo the head and cam chain...then it will run...

Some claim they can 'feel' TDC with a drink straw in the spark plug hole but it has never worked for me...might be worth a try...

[seanstr]

TDC