First Time Flex Drive Install Into Hydro

[a53hoop]

I am building a one tenth scale hydro from Gary Finlay plans. Just received all hardware and motor, etc., from Offshore Electrics on their recommendation, for this boat.
Have had no experience with flex drive, with no one in close proximity to ask.
Speed Master 21 Hydro Strut
OSE.187 cable complete
1/4 inch diameter brass tubing for stuffing tube
Question: Do you insert stuffing tube into strut, or leave it a short distance away? The bushing is very loose in the strut, and fits inside the stuffing tube. What retains the bushing and the strut?

Any offers of help is much appreciated.

Al

[martin]

The stuffing tube should go into the strut all the way to the rear of the strut, the bushing then goes into the stuffing tube with the lip at the rear to stop the bushing going right into the stuffing tube. These are known as floating bushes, the prop shaft spins inside the bushing whilst the bushing also spins in the stuffing tube. This method of bushing reduces wear on the shaft & bushing with both parts spinning, you need to leave the normal gap of around 3/16" between the rear of the strut & the drive dog to allow for flex wind up. This gap also lets the bushing float in the 3/16" gap whilst spinning, hence floating bushing.

[a53hoop]

many thanks martin. this is exactly the info i was after.

[a53hoop]

does the lip on the bushing install so it is flush with rear of strut or does stuffing tube go right to rear of strut with lip of bushing exposed at rear of strut. thanks AL

[martin]

does the lip on the bushing install so it is flush with rear of strut or does stuffing tube go right to rear of strut with lip of bushing exposed at rear of strut. thanks AL

You can do it either way, just make sure if the stuffing tube is set in from the strut face that the the bushing still spins & the lip isn't rubbing on the strut depending on the o/d of the bushing lip to the strut bore.

[785boats]

With the stuffing tube going all the way through the strut, the ability to adjust the angle of the strut is gone.
I prefer to just place an insert into the strut, for the bush, stopping about 10mm from the front of the strut.
Then cutting the stuffing tube to stop about 5mm from the insert, when the strut is set level.
This allows some adjustment for the strut, as long as the solid part of the shaft stops short of the end of the stuffing tube allowing the flex to bend at that point.

[martin]

As Paul explains you can use 2 separate tubes to get more angle adjustment on the strut if needed.

[a53hoop]

As Paul explains you can use 2 separate tubes to get more angle adjustment on the strut if needed.

the insert that youu place inside the strut would just float with the bushing floating inside ???

[785boats]

No. The insert should be a snug fit in the strut. It shouldn't turn.

[martin]

If you should find the insert is not a snug fit in the strut then a dab of Loctite bearing fit will secure things.