plug chop / break in

[hedgehog]

so what should i preform first, plug chops/setting up the carbs or break in for two tanks?

both are inportant i know, but im thinking run rich for the break in. then do the chops.

also where is a good place to ground all three plug wires wile compression testing on a 95 sl750?

[32DegH2O]

Most definitely the breaking in the engine...plug chops require full throttle runs...something you don't want to do on a new engine. The best proven way to break in an engine for a long lifetime is the following...

Make sure you use the right oil and have the right gas oil mixture 40:1 if you have a two-stroke...I would use this in my first tank at least if not also the second. As for break-in, from the best reports that I have read and my personal opinion based on knowing people in the Polaris design for the watercraft division, the best thing to do is to ride your jetski for only 15-20 minutes at a time for the first three times you use it. Be sure that the engine gets to cool off completely between the first three rides. On the first ride, do not go over 1/2 throttle, the second ride go only 3/4 throttle and on the third ride go full throttle a couple times but only for about 10-15 seconds. Also, vary your throttle speed as much as possible as you ride. What this all does is get all the engine components up to operating temperatures and then allows them to cool down, it conditions the metal parts due to the expansion and contraction due to the temp changes. This will break-in your jetski for a long life. After that, balls to the wall and have fun!

[hedgehog]

ya thats what im thinking too. so i should set the carbs rich for the break in. how will i know they are rich for sure?

[32DegH2O]

Here are the stock carb settings for your '95 SL750:

750 - Low Speed – 1/2
High Speed – 1m, 1/2c, 3/4p

I would set the carbs to this and with the 40:1 premix gas in the tank you should be more than covered for the break-in period. Then start your plug chop testing...good luck!

[gldnrober]

I may be way off here isnt the normal premix 40:1? if thats is what to use for break in what is normal to run premix?

[ph2ocraft]

On a modern day system they are variable pumps, so at idle they are much leaner than 40:1. So if you pre-mix at 40:1 and are breaking the engine in you may not require more. I personally like it at 32:1, but that's just me.
If you go from oil injection to pre-mix you want 40:1 but need to keep an eye on things as the oil is displacing fuel, so you wind up a little lean.
If it's injected and you want a little more protection add accordingly.