Noisy dog bone setup

[secrtwpn1]

Attached is a photo of my dog bone setup. It seems noisy. Is it the nature of the beast or am I doing something wrong?

Thx
Farlan

[Ralph --- SSBN 598]

Farlan,
it appears you may have the two brass pieces too close together.
Should be about 1/8" slack between the brass universals to let the dog bone move back and for in the slots.

Also make sure that the dog bone is not touching the motor and or propeller shafts.
There should be at least 1/8" clearance there as well.

[secrtwpn1]

So, should I lengthen the dog bone??????

[Ralph --- SSBN 598]

Looking at your photo, it appears the dog bone assembly is near straight.

What I suggested is that you put more distance between the two brass universals.
Give 1/8" clearance from the brass pieces to the nylon pins on each end of the dog bone piece.
Now, this would mean that there should be 1/8" clearance on one pin and not both.

Loosed the screw holding one brass end piece.
Hold the dog bone tight against the end that is not loosened.
Slide the loose brass piece to get the 1/8" gap and tighten screw.

If the dog bone touches the end of either the motor shaft or the propeller shaft, one of them to get the 1/8" to 3/16" clearance.
=======================
The ends of the dog bone must not touch the either shaft when in place.

If it does you need to shorten the shaft on the propeller side.
Move the rear brass universal back towards propeller.
Now insert dog bone in to the front universal all the way.
Do the pins on the dog bone bottom out in the universal or do the pins not touch the universal slot bottom?
If the pins touch, move the universal back until the dog bone pins touch the bottom of the universal slot.
Tighten universal set screw.

Install dog bone in to both universals.
The dog bone may touch the rear shaft.
You should have about 1/8" clearance here.
Cut or grind a little off the rear shaft to get more room for the dog bone.
Once the shaft is to length clean up the end of the shaft. (file sand paper)
Put the dog bone in the front universal and then slide the rear universal forward until the dog bone is in both slots.
Move the dog bone all the way forward in to the forward universal.
Slide the rear universal forward until the dog bone pins are engaged in the slot.
You should have 1/16" clearance from the universals to the pins at both ends.

The dog bone should move back and forth about 1/8" in the slots.
The dog bone should not touch either shaft.

Wow, took longer to say it than do it!

[PaulC]

Is the thrust bearing bulkhead actually supporting the shaft? The bearing doesn't look like it is affixed to the bulkhead.

[secrtwpn1]

It is attached to the bulkhead.

[subdude]

Define "noisy" please. Rattling? Squeaking? Groaning?

While Ralph is absolutely correct, I've never heard a tight dogbone make any real noise.

In looking at the photo, it appears as though you have a brass prop shaft running in a brass support bearing. The moving parts should be of dissimilar materials else they will eventually gall and seize. If it's squeaking or groaning, I'd suspect that. Either change the shaft to stainless, or the bearing to bronze or plastic (delrin, rulon, etc)

If it's rattling, I'd suspect he fit of the shaft in the bearing.

But do, as Ralph says, make sure you have 1/16 - 1/8 play fore - aft in the dogbone between the cups.

Jim

[secrtwpn1]

Its kind of grinding.....I will change the shaft to stainless steel. Thanks for all the adivce. I'll be out out town for awhile (moving daughter from CA to WA!!!!), and will try it when i get back!!!!!!!