jeff beckley
Well Known Member
On my RV7A when we mounted the engine I thought we payed close attention as to which mounts go where. Soft verses Hard. We then proceeded to install the engine cowl allowing for 1/8" sag. We did notice that there was a slight difference in the gap between the top of the spinner and the bottom in relation to the cowl. 1/8" wider at the bottom. I planed on laying up some filler on the cowl to even this out before I painted.
The other day I made a comment to an experienced builder about the gap and he suggested that I may have reversed the mounts. Says I should go check them. Well to my surprise I did in fact have them reversed.
Now what to do?
If I go in and switch them around will my position change in relation to the prop?
I now have the soft mounts behind the cup at the top and the hard in front against the engine.
If I do nothing at all will that cause a problem? Additional sag latter on?
It seems that the geometry will change if the mounts are of difference thickness. If so, can a couple of washers strategically placed bring the center line of the prop back? I cant reposition the cowl as it is installed.
Is the thrust angle up or down changed if the mounts are wrong?
The other day I made a comment to an experienced builder about the gap and he suggested that I may have reversed the mounts. Says I should go check them. Well to my surprise I did in fact have them reversed.
Now what to do?
If I go in and switch them around will my position change in relation to the prop?
I now have the soft mounts behind the cup at the top and the hard in front against the engine.
If I do nothing at all will that cause a problem? Additional sag latter on?
It seems that the geometry will change if the mounts are of difference thickness. If so, can a couple of washers strategically placed bring the center line of the prop back? I cant reposition the cowl as it is installed.
Is the thrust angle up or down changed if the mounts are wrong?
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