Static and Dynamic timing for a 1200 engine

[ryanbgb22]

Well after talking to Jay from Atlantic, It seems that it is VERY important to check timing once I get my ski back together.

First off, How do I check timing?

Second, Is there a way of starting then engine or something outside the ski so I dont have to screw around with it in a hard to reach location? I honestly have no idea on timing.

[TxVirageTx]

timing

got a dial indicator????i've bench timed both motors and they were right on

[ryanbgb22]

Could you explain / lead me to the process of doing it this way?

[Hurban96]

I'd like to know also. I'll have my 1200 back together this week

[TxVirageTx]

Using Dial indicator to set static timing on 1200 engines

disconnect stator harness; connect 9 volt battery + on stator Brown, battery - on stator Gray

Ohm meter - probe on Gray, ohm meter + probe on stator Red wire (which is the MAG cylinder Hall Effect sensor)

Check Hall Effect trigger while turning flywheel in direction of rotation only. Set to trigger at .350" BTDC on 1200's (40 degrees static timing) with normal flywheel.

Note: High Start CDI need another ten degrees of base timing.

[K447]

Static timing tools for Hall Effect stators

[ryanbgb22]

So, I'd use this process during the build, after its together i'd check with a standard timing gun and hope all is good?

[ryanbgb22]

Ok, so I understand hooking everything up as far as the multimeter/led, but how do I actually check the timing from this point? When the led lights, the cylinder testing should be at TDC? Am I thinking correctly here?

[K447]

Have you looked at the procedure notes in the Service Manual?

[CumminsAholic]

It should light up before it gets to tdc. I'll try to help...

• Turn it over ( the way it normally turns) til you find top dead center.
• Make a note of that measurement on the dial indicator.
• Now turn the motor back, slowly so the led goes out.
• Then turn it forward again til the led lights up. You should be at .350 less than than your TDC number when it light turns on.

Say the TDC was 1.675 on the dial indicator then you should be at 1.325 when the static timing light turns on. Adjust the flywheel timing ring accordingly to get the Hall Effect sensor to trigger right at .350" before top dead center (BTDC) measurement.

Hope that helps.

Tx do you know the magic # btdc for the 785's?

Corey

[ryanbgb22]

Very clear! Thanks alot.

[TxVirageTx]

timing

light or volt meter moves when the piston reaches .350" before tdc in direction of rotation. you gotta count needle revolutions and always back rotate past so you are approching the trigger in the direction of running rotation.

The Hall Effect sensor trigger must happen way before 25 TDC. The CDI is a timing retard unit. By triggering it at 40 degrees before TDC the CDI is always taking away timing. No way a CDI unit can fire before its triggered.

[ryanbgb22]

light or volt meter moves when the piston reaches .350" before tdc in direction of rotation,you gotta count needle revolutions and always back rotate past so ypu are approching the trigger in the direction of running rotation.the trigger goes way before 25 tdc.the cdi is retard unit.by triggering it at 40 the cdi is always taking away timing .no way a cdi unit can fire before its triggered

Im not really following you. What do u mean by needle revolutions and the numbers 25 and 40?

[TxVirageTx]

dial indicator

as you rotate the crank back and forth from tdc to btdc its easy to actually go a full revolution on the dial, 25 degrees or 40 degrees.

but you have to go past 40 degrees BTDC to reset the trigger sensor every time so as to trip it properly in the direction of running rotation.

[ryanbgb22]

as you rotate the crank back and forth from tdc to btdc its easy to actually go a full revolution on the dial,25 degrees or 40 degrees.but you have to go past 40 to reset the trigger every time so as to trip it in the direction of running rotation

oh ok, i think i follow you...thanks

now where can i rent / buy for cheap one of those dial indicators or whatever that tool is called?