120 V4 timing adjustment

[MarkHPCA]

My Clymer book says to check/adjust the max timing on my 86 120 looper at 4500 RPM using a tank and test wheel and not to use the propeller. As I don't have access to a test wheel is there another suitable method I can use? I don't think hanging off the back of the boat at 50 MPH is a good method and as my timing light uses 120V I would need a very long extension cord

 

[Hotrods]

Re: 120 V4 timing adjustment

Take pics please...lol

 

[Dhadley]

Re: 120 V4 timing adjustment

We back the boat and trailer down the ramp and adjust it forward and back so we can run the motor in gear and get as close to wot as possible. 4500 is a minimum we look for. <br /><br />Just make sure the boat is secured to the trailer and proceed slowly. Its normally a 2 person job.

 

[MarkHPCA]

Re: 120 V4 timing adjustment

I have visions of the boat sitting on my roof-rack....<br />I was reading a procedure described by J Reeves in which you set the timing by just cranking the motor. Is this procedure applicable to larger motors?

 

[Solittle]

Re: 120 V4 timing adjustment

Yep.

 

[rodbolt]

Re: 120 V4 timing adjustment

it still needs to be verified. its not that difficult. its a bit unnerving to sit beside the motor at or near wot. my fist session with a dyno was with a 200. but once ya get used to the noise its almost as good as sex. maybe better sometimes. if you do this on the water make sure a trusted friend with no ties to your life insurance is at the helm.<br /> good luck and keep posting.

 

[MarkHPCA]

Re: 120 V4 timing adjustment

How about triming down an old prop and use it as a test wheel ? Would this be sufficient