Hi, I have my cowl all in place, mounted and I am about 2mm off on the drive washer sticking out of the cowl. In other words, the drive washer is not sticking out far enough.

When I go to put the spinner back plate on, it will probably rub the cowl once I start the engine and the vibration.

In stead of refitting my entire cowl, can I stick some kind of spacer between the engine drive washer and the spinner back plate?

I hope I explained that correctely.

Thanks!

In your case you would probably be better off placing washers between the engine mount and the firewall. This will give you the extension you need.

Ken</p>

+1

Bonebreak

How did you come by that screen name?

It is my last name. Really..

washers work well enough they also will dig into the firewall over time you can use thin 1/16 aircraft ply, to make a spacer to fit behind your engine mount then you will have full contact between your engine mount and the firewall.
a little thinned epoxy and your fuel proof and good to go,I have done the washer thing on a couple of models now, mainly to remove thrust angle, and over time they all seem to dig into the firewall, when this happens fuel can get to the wood, and it starts to soften making the problem worse, really gradual so you won't notice it at first.

Yup, washers dig in over time.

I found that large fender washer's do a MUCH better job of spreading the load and force, preventing damage and problems.

You can find these in any hardware store.

Typically I use 1" or larger diameter fender washers.

This works better than a ply spacer.