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lewy 12-07-2010 09:48 AM

Firewall Bolts
Great work on this issue. Currently waiting on finish kit, just wandering how the actual engine mount mounts to the firewall? If it is bolted to the firewall has anyone checked these bolts for looseness? Just a thought.

dick seiders 12-07-2010 11:39 AM

Lewy, those bolts are locked with a cotter key after torqueing.
Dick Seiders

Jetguy 12-07-2010 04:17 PM

Answer to your question!
Lewy. Go to this link and you will see on page 10 how the motor is bolted to the firewall.

lewy 12-07-2010 09:23 PM

Thanks for the info, engine installation looks pretty complicated. I'll study section 46 this winter. Temps 19 degrees in southern Ohio tonite.

dick seiders 12-09-2010 04:43 PM

I know this thread has spoken for most of the issues concerning it. I did however promise to report my findings on the bolt check. I reported earlier that the bottom two had maintained the 312 inlbs. I am pleased to report today that the top left was still at the original torque. The top right bolt moved between 1/16 and 1/8" only on the torque check to 312. I have 43.6 hrs on the flight log. I will follow with the 360in lbs with 242 Loctite, and mark with torque seal tomorrow. I plan to visually check bolts at each oil change which in my case is 35hrs. (personal choice as 3-4mos are usually required to fly off 35).
I would also like to comment that in my opinion this thread was worth it's weight in gold for all of us flying/building the 12. Thanks to all who contributed. We have a very valuable problem solving tool in these forums.
Dick Seiders

JBPILOT 03-17-2011 12:30 PM

225 hour bolt check - -
I am changing oil and other things today, at 225 hour. The 4 bolts all seem to be exactly where I left them, so I didn't touch them. BLUE LOCTITE. Over 100 hours now, and NO PROBLEM ! ! ! As I have said all along - I highly recommend 'BLUE' on these bolts. Torque seal mark them, and you should be good to go without worry.

John Bender

Tony_T 03-17-2011 06:32 PM

Bolt check
I had to remove the cowls today for a different purpose and because they were off I checked the engine mount to engine case bolts. Earlier in this thread I indicated that I was going to try the Nord-Lock washers and I did install them (no loctite). I have put 16 hours on the plane since then, not a lot since it has been a dreary snowy/rainy winter here. Anyway, I put the torque wrench on the bottom two bolts and the wrench clicked at 30 foot-pounds with NO movement of the bolts. That felt good.

A visual check of the top two was made since I did not feel removing the carbs was warranted at this point. They passed a visual check.

The Nord-lock washers are still unproven in the field for this particular application, but first indications are that they do work.


Mark Henderson 05-19-2011 08:51 PM

I just did the modification of the cooling shroud today. I did not use the method that Vans suggests. Tony T has a picture on his photo page that I followed as a guide. Instead of grinding just the inboard corner and then glassing in a patch, he cut a segment of the shroud out. You don't need to buy a ball end allen, you can use a standard allen on a 3/8 drive. It only took 15 minutes to cut the piece out with a hacksaw blade. I used a #6 nutplate and screw to hold it in place. See his photo log for details. I think it is a much better way to go.

Peterk 05-20-2011 09:39 AM

As a side note, when this first started I took all four of mine out and re-torqued them to 30 (instead of 25) as Van's suggested. 30 ft/lbs is also the number for that bolt in that single situation in the Rotax Maint Manual. In 50 plus hours of flying since I have checked frequently with no change...all four. I do still own four Nordlocks that I will install should they loosen.


Jamesey 08-03-2011 01:25 PM

Problem Solved
Not at this stage yet but by the lack of posts on this issue I assume no further problems reported on flying 12's ?

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