Engine Mount

whpilot · #1 06-14-2022, 11:18 AM

When in the building process of an RV-6 is the best time to install the engine mount? The instructions say after the wings and empennage are attached but it would seem to be much easier before that and before the forward fuselage is skinned.

rv6n6r · #2 06-14-2022, 11:51 AM

I imagine FWF work involving penetrations and the like being a little easier without the skins on. But it seems like that would be before you get past the upside-down on a jig stage which doesn't make sense? I don't know, it was a long time ago for me, but I do remember that it's relatively simple to put the mount on / take it off while you work on FWF stuff; you may do that a few times before final engine hang etc. anyway.

I did all the FWF before the wings since I was working in a single car garage - the wings only went on once I got it out to a hangar a few months before first flight. I'm not sure why the instructions would say to do otherwise, maybe it's more about the -6A types?

A slight tangent here - if you have an old engine mount make sure it has the reinforcing gusset mod at the gear leg bottom intersections, or if not get that added. Pain in the butt since there's stripping and re-painting to be done, but way easier now than after cracks develop (ask me how I know / see pic).

PaulvS · #3 06-14-2022, 08:38 PM

I am building a -6A and have not yet installed the engine mount. The wings have been temprarily fitted and then removed while the fuselage was still in the jig, in order to align and drill the gear legs and sockets.

All of the fuselage skins are now riveted on, except for the top forward skin. It will need to be in place for the wind screen part of the sliding canopy. But it is much easier to get access to the sub-panel area for wiring and avionics placement without the skin attached. There is limited access to finally buck the rivets on this skin and one option is to reach through the recess on the firewall, without the engine mount installed. Another option is for someone to crawl inside under the panel to buck the rivets.

It will be much easier also to install the canopy without the wings on.

The engine mount may restrict access for riveting the cowl hinges and applying sealant around the edges of the firewall.

The Vans instructions were probably written for people who did not yet have the finishing kit, I think the engine mount might have been shipped in the finishing kit?

lr172 · #4 06-15-2022, 10:47 AM

Quote:

Originally Posted by whpilot

When in the building process of an RV-6 is the best time to install the engine mount? The instructions say after the wings and empennage are attached but it would seem to be much easier before that and before the forward fuselage is skinned.

definitely no need to have the wings on for this. I installed it before the top skin also.

Larry

wirejock · #5 06-15-2022, 05:12 PM

I would fit the mount just like wings and remove it. Wait as long as possible to install the mount. The holes can be utilized to mount a rotisserie.

abwaldal@gmail.com · #6 06-15-2022, 05:57 PM

I have a 1991 RV-6 and I put the mount on as soon as the fuselage was done. It allows you a real good idea as to the interference of the junk you want to put on the firewall.
Comes off in 10 minutes. Make sure you do the gear reinforcement mod if it hasn't already been done.
Art