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Broken short leg RV4 engine mount help!

Freddyboy

I'm New Here
I was looking for advice from someone who had a “short” leg mount and has installed the “long” leg mount and gear. Van told me it could be 6 months or longer to get the new mount and gear. Does the new mount match up with old bolt holes? Thanks for any help!
 
Are you sure your current mount is beyond repair? As another short leg -4 owner who is in the process of pulling my mount for crack repair (hope it have it off today) everything I’ve seen is that the long leg change is quite involved.
 
I just read the newest Kitplanes online last night. There was an article by Paul Dye about repairing an RV6 engine mount.
 
I would definitely check with Russ McCutcheon - he’s a marvel at this stuff, and probably built your mount in the first place....

Paul
 
Thanks Paul I did talk with Russ (great guy) he detailed the history of how Van’s gave the engine mount business to his predecessor because of the quality of the build. He said if the mount was repairable it would be $1200. He recommended to go with a new mount and gear, citing lower landing and takeoff speeds due to the higher AOA the longer gear legs provide plus higher resale value. My neighbor recommended checking with the F1 Rocket crowd to see if anyone that converted a 4 and had a mount for sale. I guess Russ has the only jig to make up the newer long leg mount.
 
I was looking for advice from someone who had a “short” leg mount and has installed the “long” leg mount and gear. Van told me it could be 6 months or longer to get the new mount and gear. Does the new mount match up with old bolt holes? Thanks for any help!
The long leg mount does not match the center firewall holes. About an 1" or more difference. I swapped my short mount for the long one and had to re-do the firewall and new center mount pads. I still have the short mount and gear legs - like new, never been flown although they were mounted on the kit.
 
How bad is your engine mount do you have pics? Where are you located? These mounts are 4130 chomoly and very easly repairable. I have cut out rusted, bent, and totally rebuilt Bell 47 helicopter center frames. There is not much to a RV engine mount comparatively speaking. Maybe I can help $1200 seams excessive
 
As someone who has done the swap I will say there are many things that change when you do the swap. Its not as simple as remove one and install the other. The wheel pants are at a different angle, your intersection fairings wont work gear leg fairings will have to be redone. If you are lucky everything will jell with your cowl and baffles. Its totally doable just want to say you could be going down a path you might not like. If it were me I would find a local shop with a good welder and look into getting it repaired. Probably a lot less expense and a lot quicker.
 
R&R vs R...

I was looking for advice from someone who had a “short” leg mount and has installed the “long” leg mount and gear. Van told me it could be 6 months or longer to get the new mount and gear. Does the new mount match up with old bolt holes? Thanks for any help!

Hey Fox Bravo,
I agree wholeheartedly with repair vs replace. There are plenty of talented welders in Central FL, I used to live there.
Years ago I R&R'd my Conical mount RV4 short gear for a Dynafocal short gear in lieu of installing a Hot Rod 0-320. I chose to remain short gear as I wanted min down time, easy swap hole for hole, same legs and fairings, brake lines etc. A guy on this site swapped me even including legs as he wanted everything matched. I broke protocol and powder coated the new legs and mount bright red and reinstalled with the new engine.
Easy peasey..
I've flown numerous RV4's with long/short/bent and otherwise landing gear. Yes, Long Gear Fours land a bit better in 3 point, get off a tad quicker due to the increased AOA and look better, otherwise it's moot. My home strip in FL back then was 1500' of rough, soft turf with trees. No worries.
Arguably the short gear has better forward visibility, lighter weight (by a smidge) less drag and lower cost to keep or repair rather than replace.

It all boils down to the $$$.
:)
V/R
Smokey
 
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Soft turf

Smokey...your last strip was soft turf? Really??? Did it have gopher holes too?

It seems that someone with less aviation skills than yourself would get stuck in a field like that...(while trying to launch a 10 ship)...

Yes, and that someone would BE ME!!!!! :D
 
Engine mount cracks

I had cracks on my RV-6 engine mounts possibly aggravated by flying into uneven grass strips. I pulled the engine and engine mount and got it welded up along with Van's supplemental gusset kit. It was not that hard or expensive to do. The trick is to find a knowledgeable qualified welder. That was maybe 5 years ago - haven't had any problems with it since.
 
Short Mount

I have a short gear leg engine mount with gear legs - Dynafocal and it had an O-320 hanging on it. I recently swapped to the long mount/gear leg set-up.
 
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