painting the engine mount, polishing the firewall.

[jetdriven]

So as detailed in the "Making metal. Here we go.. into the abyss...." thread, we detailed our discovery of the engine making metal and reason for replacement.  Well, the engine is off the airplane and it is stting for 30 days while Lycoming builds us a fresh factory overhaul. Time to get ready.

The engine mount and firewall look like pure hell. 

The engine  mount is pretty coated in rust, and half the paint is off it. I can find strangely little info about the refinish process except a few over at VAF (Vans airforce forums).  Anyways, I am looking for input from someone who has done this before. My best guess is sand the rust pits out, hit the whole thing with a red Scotchbrite pad and metalprep 79 to get it bright, stainless wire wheel on the welds to get those clean.  Then water rinse, wipe down with lacquer thinner, prime with epoxy primer, then Matterhorn White urethane single stage (Imron, Nason, etc).   Sound good?

The firewall is stainless, of course, and after 34 years it looks pretty ratty. Dull and spots of corrosion in places. A few of the VAF guys have polished that stainless like a mirror and it looks fantastic.  I am not looking for a mirror, but shiny will do to complement 35 grand worth of new engine, silicone hoses, new baffles, etc.  I also think it might reflect some of the heat generated by the powerplant; as you all know the M20J at least, is a pretty warm airplane in the summer.  However again, not much info.  Has anydone polished stainless ?

So, instead of giving advice, today, I am asking for some.  Perhaps it helps the next guy in my predicament.  

One more thing, as of Monday June 18th, the factory has waived the $3,500 dissimilar core charge to swap an -A3B6D engine for the -A3B6.  So, you get the roller camshaft and independent Slick mags and a Lycoming factory overhaul engine for $27,500.  Goodbye dual-mag. Sniff..Sniff....  I don't like Slick's or the 20 degrees timing they come with, but there are work-arounds for both.   Look for more info when we get ours installed.

Thanks

byron

[KSMooniac]

Wow, surprisingly your J (that is 5 serial numbers newer than mine!) looks a lot like mine under the cowl.  My engine mount is in better cosmetic shape.

I too plan to shine everything up when I have my engine off, but haven't researched the specs/techniques yet.  Regarding the mount, I think it would be wise to send it to an expert to get it NDI'd before you put any labor into it.  A shop might even be able to refinish it for a reasonable amount too, versus many hours of labor that I'd expect either of us to put into it.  I'd rather spend the money to make sure my mount doesn't have any cracks or internal corrosion and spend the hours shining the firewall.

You might query Eldon about what he has done in the engine compartment...his '77 J will for all intents and purposes be new when he is done soon.  It is beautiful.

That is great news from Lycoming.  I'm not sure I'd be excited about Slick mags, but I know you wanted to ditch the siamese Bendix.

[Guest]

I polished my RV 7 firewall and used Nuvite grade C and S, you may also need grade F. Google and call Nuvite they will set you up with what you need. Polish with either a Cycloe buffer or a high speed orbital with WOOL PADS, I wouldn't bother with the cheap Wallymart  auto buffers. Almost forgot I also did my mooney baffles when I did the engine, and it came out good, a older firewall will take a bit more work but it's sure worth it. 

Id also seriously consider Sending out the mount for inspection then powder coating , sure would hold up and look good. 

Good luck 

[jetdriven]

That engine mount recert is 1K.  I can do it for 5 hours and 100$.  Also, I dont think I can consider powdercoating. It can hide cracks and i am not sure it is even allowable by the feds.

 

 

[N601RX]

These people here did mine for the previous owner.  They repalced a couple of tubes, added the gussets, recertifed and painted.  It was $1k.  The old Mooney service bulletin that covers the gussets says clean, prime and paint. I would use 2 part paint and primer.

http://www.kosola.com/main.htm

[KSMooniac]

I agree on paint and not powdercoating the mount.  I'd still take the opportunity to NDI it and make sure there are no cracks...it is a fairly important piece of structure and you don't get many opportunities to inspect it carefully.

I'm curious to learn/see if you can use a mechanical polishing kit on a drill or die grinder and get to all of the recesses of the firewall on the airplane.  

Polishing or painting the baffles is a good idea too.  I think I'd opt for paint as I bet it would be nearly impossible to keep them clean and sparkly after putting in the effort to polish them.  I can't remember if they are CLAD or not...better check that out and make sure not to polish off a clad layer.

[Rustler]

Byron--

When I did the A3B6D-to-A3B6 conversion on my 1980 J, I used Varsol to remove the glop from the firewall, then attacked it with a 3M pad and about a day's worth of elbow grease. The process worked well.

I did the re-certification on the engine mount just to be sure.

[jamesm]

I had  my engine mount powder coated  on my '67 M20C  it looks nice. I used light color so cracks could be seen easier  at least in theory.

[jetdriven]

Rustler, i sent u a PM about your B6 conversion. or email me. bdr737@gmail.com

That looks exactly like I am looking for.

[Kwixdraw]

I went over the whole firewall with a brush and solvent then 3m pads to clean the corners. Started in with the die grinder and 2" scothbrite pads doing an engine turning pattern on it. Doesn't look too shabby. I'll post photos when it's complete.

[carusoam]

Datapoint...

I've seen a broken mount on the lower copilot side of a 65C before. Right where the mount attaches to the block on the firewall.

[bd32322]

anyone have a preferred shop in the northeast region to recertify their engine mounts?

 

Thanks