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720 engine swap

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davcat

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Hello Everyone: Looking for some advice.

Doing a motor swap in a 1997 GTI. The original (silver) single carb 720 threw a rod. I picked up what I think is a 1995 XP 720 twin carb (white) motor. I have been told that I can not use the original 720 CDI from the silver motor on the XP motor because of timing issues. The silver flywheel has a 10 stamped on it. The white flywheel has a 14 stamped on it. I am assuming that is degrees of advance.

I am told that I can either get a CDI for the XP motor or use the flywheel and mag from the original (silver) single carb motor, with the original CDI.

From what I have read all the 720 cranks are the same from 95-2005. If this is correct the timing should be ok with the (silver) flyweel and mag on the white XP motor.

Can anyone shed some light on my situation? I have both complete motors and dont mind swapping parts back and forth. I would have to buy a CDI if it was required. Sounds like they are hard to come by.

The end result I am looking for would be a reliable ski to run around the cottage. If it is down on power a little using the silver mag I would be ok with that.

Thanks
dave......
 
Just swap the flywheels. BUT... you will want to verify the ignition timing once you get it running.
 
Thanks Dr Honda. Would I have to change the mag also?

Could anyone verify flywheel and Mag parts comparison? I am told all 720 cranks are the same. I know they are the same part numbers when you purchase an aftermarket crank.

I have the model numbers from each motor.

The original silver GTI motor: M5104831

The white motor (assuming 95 XP): M4517087

Thanks everyone...
 
im 99.999999% sure they are the same i just did a switch on a ski of mine and i had to use the other parts and interchange and yes all the cranks are the same....let me call my guy and verify this for you
 
Thanks everyone, I really appreciate your expertise on this.

Looks like I will have to use the silver 720 mag on the white motor. The case that holds the mag from the GTI motor, has mounts as part of the casting. Different motor mount set up on the white motor.

So if there are no final objections. Using the complete white 95xp motor with the silver mag and flywheel from the original GTI , plugged into the original GTI cdi box...... sound good?????


Another issue I have is the choke cable from the GTI ski. It is for a single carb. Should I change the choke cable to a twin carb pull or use a primer? Any thoughts?


Thanks
dave.....
 
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