Hitec HS-5646WP Digtal servo not centering ?

[Andris Golts]

Hi all took a trip to the local pond to test my re-built p-spec outboard tunnel hull on its first outing had a difficult time to steering the boat realised the steering wheel on the tx and the boat would hook to the right once back on the stand checked the steering and noticed when realeasing the wheel on the tx the o/b would not return to centering position would stay slightly to the left or the right and on ocasion center itself. the HS-5646WP is mounted close to the o/b with the heavy duty servo arm connected to a pair of 2 3/4'' long 4-40 pushrods to a pair of 4-40 swiwel links im using a Futaba 3PV radio with a Futaba R2104GF reciever . Any suggestions to remedy this nightmare would be welcome. May be i should of stayed with my Futaba 3305 analog servo and the 7 1/2 '' long 2-56 pushrods that was from the original build. Regards Andris Golts.

[rol243]

Have you tested the servo with the outboard motor disconnected ? What System Type is the TX in? if its in T- FHSS try going to S-FHSS or other .

[TheShaughnessy]

that servo only has 157 oz/in of torque, which would be fine if this was only turning a rudder. I don't run any outboard tunnels so take this with a grain of salt but I would try to find a servo with much more torque, those outboard units can really put a load on a servo, especially when compared to just a rudder. You can also check the settings on your radio, idk about the 3pv but on the 4pk you can switch between hi speed brushless servo and standard servo, double check to make sure its on the regular servo setting.

[Andris Golts]

Thanks to both of you for the excellent information i remeber a year ago when i bought the radio i had the shop owner set it up for analog servos. Regards Andris Golts.

[NativePaul]

The symptoms also match a worn dirty or corroeded potentiometer, how much use has it had? Has it been wet? (I know it says WP, but I dont trust anything to be, unless I have treated it myself.)