Need help on TDC on a 480 finner

[farmfuel]

HI all,

This is my first post. I picked up an 83 CR480 for 50$ last year. I had to push start it to get it running. Once it runs, it doesnt have any power, and won't get up on the pipe. So i thought it had jacked up reeds. Changed them, but it didn't help. Then I discovered the head gasket was leaking (you could see it), so I tore down the whole motor and split the cases. The cylinder wall was .020 past service limit, so I punched it out 1mm over. I also installed new crank seals. Put a Keihin PWK 38mm Air striker on there with what I think are the correct jets, and still didn't help. Even after overhaul, it still runs lilke crap. So then, I go to check the timing. It's off, so I adjusted it. I got it hitting about damn near dead on, but with the timing light blinking, I notice that the marks intermiddently cut out. So I suspect a bad CDI box. I've already replaced the stator with a used unit that ohmed out good, replaced the coil, and it still runs like crap. So now I've got one hell of a money pit going, and I went off and ordered a PVL ignition, but my problem is finding TDC using a dial indicator...I can't get it to fit in there, due to the cooling fins being in the way. Does anyone have any ideas as how to find true TDC for this PVL ignition?

Thanks for the help- David

[Roostius_Maximus]

the crank key is in line with the con rod.

here is the no tools way of finding tdc

pull the head, stick a degree wheel on the crank, it can be anything you want as long as you can mark it.
Start by finding something flat to set across the cylinder.
turn the crank clockwise until the piston contacts the something flat you set across the deck, mark the "degree wheel" when the piston is in contact.
Repeat as counter clockwise.
You should have 2 marks on your wheel, measure that distance in mm and divide by 2
make a mark at your new number, this is your TDC

[AlisoBob]

Bet you $20 the piston is in backwards....