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sonny1717
10-30-2011, 05:18 PM
How do I get rid of the high pitch squeal in the drive system in my new mystic , also have made several adjustments and can't get it to stop cavitating , meaning , when I'm all out , the bow is slapping up and down , please bail me out !!!! Thanks

desmobob
11-01-2011, 07:56 PM
Greasing the flex shaft and strut bushings will kill the squeal for a few runs. I replaced my strut bushings with lead/Teflon bushings from OE and they no longer make a peep.

Cavitation has nothing to do with your bow slapping up and down, but to help sort out the porpoising, try raising your strut even with the bottom of the boat, then experiment with the boat's center of gravity by moving the batteries forward or aft to fine tune things.

Take it easy,
desmobob

Derrick Davis
11-02-2011, 01:26 PM
Those are good tips desmobob. I experienced the same "squealing" sound after my first 2 runs when it was new out of the box. Annoying.... to say the least. Can not stress enough how important it is to keep the flex shaft AND strut bearings greased. I grease after every run (OR two depending on how long I run). No squealing since. But, it's just a matter of time that the stock bushings will wear out. When they do wear out....they could seize. I need to order those strut bushings like you have suggested desmobob! :thumbup:
As most here would probably agree, the center of gravity is key to reducing the amount of porposing.
Have a nice day. :popcorn2:

sonny1717
11-02-2011, 11:24 PM
Thanks guys will do , I know I seem like a rookie but I have several boats and this one just will not stay in the water , I'll make the appropriate changes and get back to you , peace !!!!

DURAMAX11
11-02-2011, 11:26 PM
One thing I noticed on my new mystic was the motor was not aligned perfectly with the stuffing tube. I would hit the throttle and the prop would spin and stop. I aligned the motor and now when i let off the throttle the prop still spins for a few seconds. You may want to check that.

Steven Vaccaro
11-02-2011, 11:47 PM
Greasing the flex shaft and strut bushings will kill the squeal for a few runs. I replaced my strut bushings with lead/Teflon bushings from OE and they no longer make a peep.

Cavitation has nothing to do with your bow slapping up and down, but to help sort out the porpoising, try raising your strut even with the bottom of the boat, then experiment with the boat's center of gravity by moving the batteries forward or aft to fine tune things.

Take it easy,
desmobob Did you dill the strut to take the 1/4" od bushings?

desmobob
11-03-2011, 05:41 PM
Did you dill the strut to take the 1/4" od bushings?

I didn't have to do anything to my strut to use the Octura 3/16" bushings I bought from you, Steve (part # oct-oc6ltsb). The only thing I had to do was shorten the length of the rear bushing so it didn't hang out of the strut. They work well... no more noise!

Take it easy,
desmobob

Steven Vaccaro
11-04-2011, 07:01 AM
I didn't have to do anything to my strut to use the Octura 3/16" bushings I bought from you, Steve (part # oct-oc6ltsb). The only thing I had to do was shorten the length of the rear bushing so it didn't hang out of the strut. They work well... no more noise!

Take it easy,
desmobob

I tried to get the bushing out and couldn't. I'm using a small bearing press. But it does have some power.
Did yours come out easy?

desmobob
11-04-2011, 05:09 PM
I tried to get the bushing out and couldn't. I'm using a small bearing press. But it does have some power.
Did yours come out easy?

Hi Steve,

My rear strut bushing came out very easily... as a matter of fact, it was sliding out almost every time I pulled the drive shaft out for lubing. The front bushing, on the other hand, needed a little encouragement. I tapped it out using a small screwdriver.

The strut has a slightly larger than 3/16" bore, with both ends being counter-bored a bit larger (1/4"?) for the bushings. In other words, the rear bushing has to come out the rear, and the front one has to come out the front.

Take it easy,
desmobob

Steven Vaccaro
11-05-2011, 07:42 AM
The strut has a slightly larger than 3/16" bore, with both ends being counter-bored a bit larger (1/4"?) for the bushings. In other words, the rear bushing has to come out the rear, and the front one has to come out the front.

Take it easy,
desmobob

HA, I found out that out after taking one to the drill press after getting sick of playing with it. thanks for the help!