Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length.

[lakeshore]

Hi
anyone know how much amps load increases by greasing propshaft ??.

Stock 600 can sized motor and 14inch propshaft
Well just bench tested this out and the results are quite alarming.
Motor draw without being connected = 1.46am
Propshaft tube greased motor connected = 17.26amps

wow must be super glue in this grease I bought, supposed to be for model boat propshafts, more likely IC not electric.
John

[boatmadman]

John,

Whilst I dont question your noted increase in amps, it may be down to more than just the grease.

 Any drag in the shaft will draw more current, as will any mis alignment through the coupling.

Having said that, too much grease WILL drag the motor down and cause overheating due to churning of the grease in the shaft. I have seen this many times at work where well intentioned mech techs pack bearings to the gunn'ls with grease only to result in overheating and a strip down, clean and re grease.

You really only need a small amount in the region of the bushes - no more.

Ian

[Andyn]

Propshaft tube greased motor connected = 17.26amps

You've put too much grease in.

[HS93 (RIP)]

thats why we use OIL , yes it makes a difference if the shaft is on an angle and the top is above the water line we have no problems with oil, most shafts have the black bearings these days or some other kind of bearing that will self oil in water , so it is only the running out of the water that you need to worry about.

what type of boat is it ?

Peter

[Andyn]

If using ptfe bearings, you only need the tiniest amount of grease, and only at the inboard end to stop water ingress. The shaft itself, unless a flexi shaft doesn't need greasing. It's a piece of steel, why on earth would it need greasing. If done properly, a system running out the water should add milliamps.

[CF-FZG]

Stock 600 can sized motor and 14inch propshaft
Well just bench tested this out and the results are quite alarming.

Motor draw without being connected = 1.46am
Propshaft tube greased motor connected = 17.26amps

But what amps with a connected ungreased shaft

and was that with a prop and in the water?? - not enough info to give an accurate answer


Mark.

[RAAArtyGunner]

But what amps with a connected ungreased shaft

and was that with a prop and in the water?? - not enough info to give an accurate answer


Mark.