B

BruceW

Well Known Member
DWG C4 shows the backing plate mounting to the prop hub with a spacer
and one AN960-416 washer. Is the washer needed? Or can I just use the spacer?

I?ve got a standard hartzell prop with the CS spinner from vans.
Done the cowling, but want to double check the spinner backing plate
spacing to the cowling. Using the washer may place the plate-cowling space too small. Would like to nix the washer if I can.

Seems the only reason is to keep enough clearance from the prop trailing edge at full rotation. Are there other reasons to use the washer?
Thanks for the input.
 
Check your Prop Manual

It covers what is acceptable in regard to the location of and how many washers. For my prop it is a minimum of one washer next to the locking nut and a maximum of 3 washers total. You will want to check you manual for the specifics of your prop but I would suspect you do not need the washer and the spacer.
Hartzell HC-C2YR-1BFP, Istallation and Removal, 61-00-15, Page 3-6 and 3-7.
 
Checked the prop manual

Good point. I did check the prop manual. It allows a range of washers in front of and behind the spinner backing plate. (Something like 'Zone 1 and Zone 2)
In front it lists none to one washer as options. So the questions still remains.
How many washers in front of the backing plate?
Any advice appreciated.
 
You have your answer....

BruceW said:
Good point. I did check the prop manual. It allows a range of washers in front of and behind the spinner backing plate. (Something like 'Zone 1 and Zone 2)
In front it lists none to one washer as options. So the questions still remains.
How many washers in front of the backing plate?
Any advice appreciated.
Click to expand...

read that part of you manual again. Mine allows for a maximum of three between both zones, and a minimum of one against the lock nut. So in my case, I could use the spacer only without a washer and one or two against the lock nut. I think that was your original question? Sorry if I am being a bit vague but your manual is god when it comes to this.
 
Thanks JonJay

Yea, that's what I got from the prop manual also.
I just didnt know if Vans put the one washer in front for a special reason.
I will rig things without the washer in front and hope the blade
doesnt hit the backplate at full pitch.
Thanks for the advice.
 
You must log in or register to reply here.