Engine mount interference 0-320 B2C

dwilson · #1 07-17-2006, 06:43 AM

I am building a 9A. I purchased a Lycoming 0-320 B2C from Aerosport Power. I purchased the special mounting weldment for the non-conical mount from Vans's. I also purchased the Lord mounting pillows/hardware from Van's.

Yesterday I mounted the engine and discovered in interference problem at the top left mount. The bolt head is VERY close to the pushrod tube, and I am afraid that when the engine is run they will impact each other.

I have attached 3 photos to show you the problem.
Is there a fix for this? Different mounting hardware/pillows? A different engine?

Thanks,
Duane Wilson
91199

herve-RV7 · #2 11-30-2006, 02:23 PM

Hi Duane,
I would be interrested to know how you have solved your problem, I 'm n the way to buy the same type of motor as you (O320 B2C).
Thanks in advance for your comments

N941WR · #3 11-30-2006, 08:04 PM

FYI - My O-290-D2 has the same mounts I did not use the Lord mounts for this reason.

Here is a picture of my mount:

One thing I keep hearing is the conical mounts don't move much so the clearance of this bolt is not an issue.

I will find out if that is true when I fire this thing up for the first time.

BTW, in the three months since I hung the engine, it has "settled" some.

mahlon_r · #4 12-01-2006, 05:49 AM

That is pretty much the way it is on all certified aircraft, using the conical mount setup, as well. I have never seen it be an issue. However, I think you should use a castle nut and cotter pin to secure it. Using a lock nut, you really aren't tightening up against anything solid as lock nut are designed to be used. You are really only snuging the nut to squeeze the rubber. That type of situation is normally better suited for a castle nut and cotter pin, in my book. If the mount had a spacer that went in between the rubber biscuits to tighten the biscuits against, making a solid assembly, then a lock nut would be more appropriate...I think. Is it common practice to use a lock nut here?
Good Luck,
Mahlon
"The opinions and information provided in this and all of my posts are hopefully helpful to you. Please use the information provided responsibly and at your own risk."