Engine Mount

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Engine Mount

Postby gme9261236 » Sun Jan 20, 2008 10:59 am

Installing the engine mount to the firewall today and noticed that it sits probably a 1/4" to a  1/2" to the right as you look on center. It appears as if it is possibly angled to the right because when we measure from the firewall to the base where the engine sits it is 8 1/2" on one side and 8 3/4" on the other. Does JA do this on purpose probably to counteract something or does the engine compensate for this when mounted? Have any of you also come across this problem?
gme9261236
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Engine mount

Postby Gerald V9 » Sun Jan 20, 2008 11:39 am

GME,
    Yes the engine mounts are designed with a slight angle so that the thrust vector offsets some of the P-factor that the propeller creates.  (The increased thrust generated by the prop blade going downward in its rotation versus the left upward  moving blade)  In trial fitting my engine mount yesterday, it seems to be about the same as yours.
                                                                         Good Luck,  Gerald V9
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Postby gme9261236 » Sun Jan 20, 2008 11:45 am

Gerald,
Thanks alot for that information. I figured that it was not a design flaw but better to verify now then after I mount it, bolt the engine on and finish the firewall forward.

Have you or anyone else used any specific tourqe settings on the 4 bolts that secure the mount to the firewall or have you used the T.L.A.R method (that looks about right)
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Postby Gerald V9 » Wed Jan 23, 2008 12:34 am

GME,
    The T.L.A.R. method certainly will work.  The max torques for the AN Bolts is really not as high as one might think.  AN3 = 25 inch-pounds     AN4 = about 66 inch - pounds    AN5 = about 138 inch - pounds    Which puts the four engine mount bolts at about 66 inch - pounds or just reef-on-em.
                                                                                Later,  Gerald
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Postby gme9261236 » Wed Jan 23, 2008 12:57 am

Thats great info again Gerald

I have found that the T.L.A.R method has been the way to go as far as the highlander build. Amazing that I would have to resort to that with the absolute in depth and thorough build manual that was supplied.
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