Putting back together a 1.8L after timing chain break. Need all relevant advice for getting Cyl 1 to TDC please!

[zelone]

OK, broke my chain at around 600 hours, a few weeks ago. Machine shop is installing all new valves and decking head, as needed. Should be ready today. The Yamaha tech I'd like to use is leaving for vacation and my season is fading. I'm reasonably handy and used to be a mechanic. Have built 1/4 mile cars, with turbos, superchargers, etc.

I'm hoping to put this engine back together, correctly, the first time. Need to get the #1 piston to TDC. I've been advised that tightening the cams in wrong order will bend valves or damage guides. I need all the advice I can get here to put it back together. Engine is still in the boat.

Links to pics and videos also appreciated! Thanks and have a great day!

 

[Scottintexas]

I'm no mechanic and the page below is for the MR1 engine

doesn't your yamaha tech have a service manual that says this same thing for a 1.8L

If not, I'd go by a local jetski shop and ask them,

 

[Ronnie]

@zelone

Here are a few links from YouTube. There are several others. I will take a look at my shop manual if you don’t have one.

good luck and sorry to welcome you to the club. I lost a chain at 506 hours.

 

[jmargo]

Since the motor is still in the boat you can try and spin the motor to TDC with a strap wrench around the rear coupler. Then you can mark either the crank snout or coupler to verify it doesn't move. At that point once the head is torqued tighten down the cam with the dots matching the cam caps.