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Ignition timing help

Rye_Guy78

Extreme
Joined
Oct 31, 2014
Messages
65
Age
54
Location
Ontario
Country
Canada
Snowmobile
2015 SR Viper LTX SE
I think I did something dumb yesterday. I had a blown head gasket on my viper. Tore the motor down, aligned the timing marks up with the dots on the cams, then proceeded to pull the cams and head out etc. When cleaning the gasket surface on the block, without thinking I rotated the motor so I could put a rag in each cylinder to prevent anything falling into them. Once all clean I rotated to motor to ensure nothing fell into the cylinders and applied a little oil. Not sure how many times I spun the motor, I have the timing marks lined up again but is it possible to have the crank out by 360 degrees? How would I check this?
 

I think I did something dumb yesterday. I had a blown head gasket on my viper. Tore the motor down, aligned the timing marks up with the dots on the cams, then proceeded to pull the cams and head out etc. When cleaning the gasket surface on the block, without thinking I rotated the motor so I could put a rag in each cylinder to prevent anything falling into them. Once all clean I rotated to motor to ensure nothing fell into the cylinders and applied a little oil. Not sure how many times I spun the motor, I have the timing marks lined up again but is it possible to have the crank out by 360 degrees? How would I check this?
Answer to second last question - no.
 
As long as #3 is set to TDC the cams will determine compression vs. exhaust stroke. Sounds like you have the cam markings correct so you should be good to go.
 
Yes, just line up all the marks.
So I’m just not understanding how the timing for the ignition works. If the spark plug fire once every two revolutions, and I have spun the crank without the cams installed could the ignition end up being 360 degrees out once the timing marks and dots are lined up. Like the spark would fire after the exhaust stroke instead of after the compression stroke?
 
My understanding is that spark occurs every stroke -- even exhaust.
 
I would perhaps look for a another verification that this is correct just to be safe. I was facing a possible complete engine rebuild of my Viper engine this spring and in all my prep research this was the conclusion I came to. Just want to make sure you are safe before starting.
 
You'll be fine. There is only 1 set of marks on the flywheel and the trigger for the ecu can't be 180 off either. Lineup all marks and reassemble.
 
As long as the crank alignment marks (II) are aligned in the stator cover window you are good. Align the cam marks and release the chain tensioner. Here's a good video setting the chain on a YXZ engine but it's the same.

 
As long as the crank alignment marks (II) are aligned in the stator cover window you are good. Align the cam marks and release the chain tensioner. Here's a good video setting the chain on a YXZ engine but it's the same.

Awesome thanks guys!!! That is a good video.
 


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