another eng mount question

[carll]

I have a C-90-14F engine to install on a 140 plane that previously had a -12F engine. The current installed engine mount is the 0451000. I see per the A-768 TCDS, note 5 that I need a (0451111) different engine mount. The note 5 mount has an addition diagonal brace presumably for a higher horse powered engine?? The -12F and -14F have the same horse power but I think the -14F weighs 4 more pounds. I also see the -14F uses different mounting hardware, than the -12F hardware.

Is there a conversion/adapter STC (or 337) out there that would substantiate putting the -14F engine on the 0451000 engine mount? If so can someone steer me to it??

Thanks

[6643]

The -14 engine uses the same engine mounts as the O200, called "Lord Mounts". The -8 and -12 use the "conical" mounts. The Lord mounts extend back about 1/2 inch farther from the engine case than the conical mounts, so, unless you change the mount your engine will be about 1/2 inch further forward and interfere with the cowl. I'd be interested to see how your installation accommodates the difference.

The additional tube in the 0451111 is to accommodate the additional power of the O200.

Lord mount is on the left.

lords_on_the_left_208.jpg (92.8 KiB) Viewed 288 times

There are adapters you can get to allow the -14 case to use the -12 conical mounts. Their airworthiness is questionable... I would say a field approval would be required.

[V529]

I suspect you may do more damage than good by trying to find a "conversion" isolator. I realize the cost of the new mount and the Lord isolators are substantial, but not having good isolators, that properly fit and support your engine could cost the price of an engine case (and complete tear down) sometime in the future. Personally, I wouldn't even consider it.