Aerovee into SII engine mount

[philipfrost]

Thanks in advance.
I have a SII and an aerovee 2180 to into it.
I’ve read on here somewhere about a engine mount to do this job. Or at least a drawing of one
with the aero injector manifold around the back down past the starter, I figure about 3” clearance is required to make it fit.
Between the fire wall and the standard mount spots.
this will also affect the CG, buy moving the engine forward,
this is a tail dragger, but has a tri wheel option frame, which may also create an issue.
or is there a different inlet manifold to help out.
hope this makes some sense.
cheres.

 

[Aviacs]

Are you asking about how the S2 welded structure should be made?
Or are you lacking the Aero Vee backing plate "engine mount" to go with the Aero Vee engine?

If it is the latter, I think Monnett/Aero Vee will sell you the parts. They don't seem to sell parts separately, but if you have either the backing plate with the serial number, or the engine with the serial# I believe they provide support. Since they now "own" this site, it may be difficult to talk about drawings unless they will provide (unknown).

smt

 

[philipfrost]

Apologies, last post was written late at night after a big day….
I have a SII restoration project and an aerovee motor previously from a Sonex And I’m trying to mount the complete motor with Backing plate and starter etc onto the existing frame and firewall.
I seem to have approx 3 “ of interference due to inlet manifold and possibly could contact the tri gear frame with the starter.
I have serial numbers if required, but not at hand.
I’ll try and get more details today after work , photos etc .
appreciate your response so far.
im trying to avoid creating too larger job then required, I can weld a frame as required,
phil.

 

[Aviacs]

I have simiar experience, and no expertise in the matter.

A PO to me (& Canadian A& P as well as instructor) had set up the S2L with a complete Aerovee, adding the lightweight nikasil cylinders . He did not have good luck with those and replaced them, later the 8 dowel flywheel became loose and destroyed the alternator. So he swapped everything out for a Diehl X, GP engine , and armstrong start. I have been debating whether to put the AeroVee system back on to regain a starter, and perhaps the somewhat "desirable" Aerovee ignition system. My S2L is a TW, but even so, the distances between the engine and other structure are tight - for instance the current magneto goes back through a metal extention/box through the firewall. I am having trouble visualizing how to fit a starter with the current exhaust header set up, which i would prefer to keep. etc.

So the only point i really wanted to offer, is that Aerovee said they will support mine with accessories, if i decide to use their backplate again; and assume that would be the same for you, since you have both the engine cases and the backing plate.

OTOH there are people who feel the Aerovee rubber bushings are too soft/sag prematurely (Compared to, say, Lyconental style with the Diehl). It is part of my ditherings on the subject, but i have no actual facts or experience.

AFA yours, if it came off a Sonex, is the plate-to-mounting frame even the same?

smt

 

[John B]

Probably the easiest thing to do to retain an electric starter is to get a Diehl top mount accessory case, and modify the nose of the fuselage to accept. The diehl case and top mounted starter can be made to fit the sonerai very well. Have to build a box on the firewall around the starter where it will stick through, but only requires some modification of the top cross tube and the engine mount bushing locations. My Sonerai has a top mount HAPI accessory case which is not available anymore, but very similar to the Diehl top mount case. My sonerai had the mods I talk about when first built but is now even more heavily modified than that. I looked to see if I had any pictures of the mods, but couldn't find any. Basically cut the top cross tube to allow the starter to pass through, between the top mounting tabs, then weld in some triangulated tubes to reinforce things.

Here is the diehl case. Not sure why their picture shows a bottom mount case but they do have a top mount case for sale. Havn't worked with Great Plains since Steve Bennett sold it, but they used to be real good to deal with.

https://www.greatplainsas.com/top-mount-starter-package-/-with-diehl-accessory-case.aspx

 

[Todd Loes]

GPAS used to have a special Diehl case that was the same mounting pattern as the AeroVee Electro-X casting. It was a little more expensive but it allowed a person to re-use their existing engine mount when adding electric start and alternator to an airplane originally set up with the Circa 1980 AeroVee stuff. That being said, I have NO IDEA how the starter location worked or interfered with anything on a Sonerai. I bring it up simply to facilitate further conversation.

 

[Aviacs]

That is an interesting note.
Mine has that Diehl casting, looking very much like the original Monnett electro-X castings, but it does not have (apparent?) provision for a starter.
Really difficult to get a photo in this confined space.
OTOH, I can see why Gaston, and the next owner who never flew it, might have had "carburetor problems".
If i keep the set up, I'll build at least a 1/2 box around the back of it, and direct some air into it.

Basically cut the top cross tube to allow the starter to pass through, between the top mounting tabs, then weld in some triangulated tubes to reinforce things.

Here is the diehl case. Not sure why their picture shows a bottom mount case but they do have a top mount case for sale.

In GP's defense - if you read the ad, it does have "top" printed in sharpie - at the bottom. So it is merely turned over in the photo

I can see how that would work - thanks for the note. Would not have thought of that space as "obvious" but there actually is a lot of space right there.

 

[iskyfly]

Greetings,
I have a very similar scenario, where I am trying to figure out a mod for an Aerovee 2180 engine on a frame that was designed for a GP engine (my accessory case has the starter at the 9:00 position). I remember seeing some pictures on the Sonex website of someone who had successfully mounted an Aerovee on a Sonerai, but I just haven't gotten that far. I don't have the tri-wheel option, so my biggest concern is how to modify the front and engine mounting tabs to accommodate the starter and the different mounting locations. I've been putting it off for other parts of the project, so if you get it done first, I'll be interested to know how you did it. (Unfortunately, I don't have good welding skills, so I'll probably have to hire this part out.)

I'm curious where you're located... may want to come and take a look at your setup, if you're not too far away and willing.

Cheers!

 

[shocktrooper]

Probably the easiest thing to do to retain an electric starter is to get a Diehl top mount accessory case, and modify the nose of the fuselage to accept. The diehl case and top mounted starter can be made to fit the sonerai very well. Have to build a box on the firewall around the starter where it will stick through, but only requires some modification of the top cross tube and the engine mount bushing locations. My Sonerai has a top mount HAPI accessory case which is not available anymore, but very similar to the Diehl top mount case. My sonerai had the mods I talk about when first built but is now even more heavily modified than that. I looked to see if I had any pictures of the mods, but couldn't find any. Basically cut the top cross tube to allow the starter to pass through, between the top mounting tabs, then weld in some triangulated tubes to reinforce things.

Here is the diehl case. Not sure why their picture shows a bottom mount case but they do have a top mount case for sale. Havn't worked with Great Plains since Steve Bennett sold it, but they used to be real good to deal with.

https://www.greatplainsas.com/top-mount-starter-package-/-with-diehl-accessory-case.aspx

I also want to chime in here. I worked with Scott Casler in AZ (Hummel Engines), and he fabricated a very high quality engine mounting plate to allow an electric starter/alternator/flywheel installation as well as a new intake manifold tube that is mated to the latest AeroVee Aeroinjector (carb). My original mount was the old style 'Electro-X' supporting only the magneto. He also supplied with the mounting plate, a 'kit' with everything I needed to include a new upgraded mag drive puck, flywheel, starter, voltage regulator, etc. I did have to have the 4 firewall standoff spools (for the 4 eng. mt. bolts) machined down to bring the entire engine aft, to original distance forward from firewall, to allow upper & lower cowlings to still fit correctly, i.e. VERY careful and precise measuring. I had to do a GREAT DEAL of measuring and mock up to give him the correct measurements to work from, but it was ALL well worth my time, efforts and money. My S2 was built as a tailwheel so my starter position was naturally preferred for 6 o'clock position...but Scott is a very capable machinist and could likely help you with whatever position you need. Just offering a bit of personal experience and recommendation here. I am attaching a few pics that will give you some idea as to my application.
Scott Casler 520-723-5283

 

[Aviacs]

Not sure who is responding to who at this point, but i am appreciating seeing options for various of the systems.
Does anyone know if a GP starter ring gear/flywheel is the same tooth pitch as Aerovee starter?
I will buy (prefer) the all-steel gear from GP; but still have an Aerovee starter on hand
Depending how things measure out, it might make sense just to mill the backplate from a plate, and put the components where they fit.

Semi-retired, but i have had a contract job out of the shop for a month, so lost time to dig deeper in mine.
It looks like the engine has to be removed to inspect & possibly to time the mag, for instance. The larger sheet metal box that shocktrooper shows gives some ideas. Is it allowed to have a door on the back side of a "firewall"? (To access the mag from inside the cockpit)?

smt

 

[philipfrost]

Many thanks to all that have responded.
im investigating some possibilities, including a response from sonex on the subject. I’m seeking clarification on some ideas sent through from sonex . But nice to know, that if you ask a question, they are keen to assist.
also great to receive enthusiastic and helpful reply’s from forum members.
I hope one day to have knowledge enough to reciprocate.

 

[shocktrooper]

Not sure who is responding to who at this point, but i am appreciating seeing options for various of the systems.
Does anyone know if a GP starter ring gear/flywheel is the same tooth pitch as Aerovee starter?
I will buy (prefer) the all-steel gear from GP; but still have an Aerovee starter on hand
Depending how things measure out, it might make sense just to mill the backplate from a plate, and put the components where they fit.

Semi-retired, but i have had a contract job out of the shop for a month, so lost time to dig deeper in mine.
It looks like the engine has to be removed to inspect & possibly to time the mag, for instance. The larger sheet metal box that shocktrooper shows gives some ideas. Is it allowed to have a door on the back side of a "firewall"? (To access the mag from inside the cockpit)?

smt

When I built the new 'mag/starter box', I built an end-cap cover with a deep margin on the overlap, (the cap overlaps the box) and secured it all way around with #10 nut plates & stainless steel screws. The new box and end cap is made of galvanized steel (not aluminum). It was my assessment that this was enough to contain actual engine fire flames, if they actually migrated all the way back to the cap covering the box. To avoid possibility of C-monoxide coming through, I sealed the entire mating-line all the way around with aluminum tape. Of course I installed a visual monoxide indicator disc inside the cockpit. I wanted no part of always having to remove the engine, simply to service/remove/replace the mag or starter. As far as "allowed" to do so...as a licensed A&P and owner / PIC of the aircraft, and also considering the Sonerai is classified as 'Experimental'...I made a personal decision to accomplish this modification. It was and is, my professional judgement that the box & rear cover, has been appropriately fabricated, installed and safetied. I am in no way "telling" anyone else that they should do exactly as I have here. That is a decision for each owner and/or, his A&P mechanic/inspector to judge for themselves. I am simply posting here what worked for me. As a retired A&P, I have witnessed far more risky mechanical applications, and questionable workmanship across the full spectrum of; GA, AG, Commercial/Business and Experimental classified aircrafts. Just saying.... But it was a good question though.

 

[Aviacs]

Thank you for posting that, with pix.
Very much as i envision.
In fact, i was at the scrap yard this week to pick up some structural aluminum for fixture making, and got some stainless "just in case" for firewall material. If, in the event, galvanized proves easier, there is quite an accumulation of that here in various gages from my oven project.

Are thinwall rivnuts considered acceptable for non-structural access panels?
https://www.libertyeng.com/products/thinwallrivnuttw/
They don't seem used much, if at all.
I can see how with vibration, they might fret in aluminum, say for attaching fairings? But for sheet steel i fail to see a downside?
(Used some 400+ in #10-24 & 1/4"-20 for the oven)

smt

 

[shocktrooper]

Thank you for posting that, with pix.
Very much as i envision.
In fact, i was at the scrap yard this week to pick up some structural aluminum for fixture making, and got some stainless "just in case" for firewall material. If, in the event, galvanized proves easier, there is quite an accumulation of that here in various gages from my oven project.

Are thinwall rivnuts considered acceptable for non-structural access panels?
https://www.libertyeng.com/products/thinwallrivnuttw/
They don't seem used much, if at all.
I can see how with vibration, they might fret in aluminum, say for attaching fairings? But for sheet steel i fail to see a downside?
(Used some 400+ in #10-24 & 1/4"-20 for the oven)

smt

Sorry for long delay in response to your last inquiry.
Nut plates offer a bit of 'play' in the threaded portion, to overcome slight mis-alignment issues between the surface that the nut plate is riveted to, and the holes drilled in the cover/access plate you are attaching. Riv-nuts are easily stripped out and more difficult to remove and replace. I ALWAYS put a dab of antisieze paste in the threaded hole of the nut plate before reattaching the cover(s)...pays dividends the next time ya gotta remove the screws...always go with stainless screws as well.
The original builder of my 2L used riv-nuts in the empennage access covers area and when a riv-nut spins out, stripps or loses it's grip...they can be real mofos to remove!...nutplates?...just 2 soft rivets to drill out and put a new plate into place.
Easy-peasy. Just my 2 cents.