Small Bevel Wheel Problems...

GoldenMotor.com

rangefinder

New Member
Oct 18, 2012
118
0
0
Des Plaines, IL
The Small Bevel Wheel Screw had come out twice.
First time it destroyed the Woodruff Key completely.
Second time it was left intact.
The threads were okay on the shaft, so I ordered a third screw.
I put some Blue Loc Tight on it this time, and let it set overnight.
Warmed up the motor, and was going up and down my street.
It was not an extended run, and revving a bit high when I engaged the clutch,
it cracked the Small Bevel Wheel. I can submit a photo, just not right now.

My question is..., Do you think something is wrong with the "Lower"?
Or, should I order and try a new Small Bevel Wheel, and try once more?

My suspicion is that is more than just the Screw & Woodruff.
 

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
all the bevel gears I've seen cracked were due to a bad woodruff key placement

there are at least 2 sizes of those keys wide/narrow that have to be matched between gear & shaft, plus any damage to one of the slots can cause problems with burrs or gouges that may change the width of the slot

add to that the difficulty of seeing if the key is located properly once the gear is on (hasn't slipped up behind the gear) and you have a job that takes great patience and some skill

if it is well in place, then a hand impact is pretty much required to get that screw tight - I haven't seen any other tool work well on these
 
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2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
I agree with Crassius but I'll add that bad primary gears are not uncommon. Some have the bore, center hole, drilled off center and even at an angle so the gear either isn't concentric with the shaft or it wobbles. This uneven movement can/will put undue presure on the gears.

If you order a new gear check it before installing it for concentricity and that the bore is drilled straight.

Tom
 

Jonda500

Member
May 10, 2014
86
8
8
Canberra, Australia
I agree with Crassius but I'll add that bad primary gears are not uncommon. Some have the bore, center hole, drilled off center and even at an angle so the gear either isn't concentric with the shaft or it wobbles. This uneven movement can/will put undue presure on the gears.

If you order a new gear check it before installing it for concentricity and that the bore is drilled straight.

Tom
Two out of four of the kits that I've bought, I had to replace the bevel wheels on because the centre holes were drilled so crooked that the gears had a quarter inch side to side wobble causing excessive noise and vibration.
 

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
I've also seen factories try to push narrow woodruff key gears onto wide key shafts, but this usually results in an eventual crack in the gear - many times, the wobble is just a gear seated poorly on the taper which can be fixed by reseating it straight..
 

biknut

Well-Known Member
Sep 28, 2010
6,628
402
83
Dallas
There's supposed to be a star washer under the screw that holds the pinion gear on.