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Old RV4 vibration isolators

Jeff Pearson

I'm New Here
Have an older RV4 and replaced the conical vibration isolators. Bought the J-6230-1 kit which has eccentric vibration isolators and spacer. The engine mount does not have an orientation hole. The spinner is now offset about 1" to the left, as viewed from the front of the spinner - originally, the spinner was in line with the cowling. I need concentric "standard vibration isolators" as shown on the right side of installation detail. Does anyone know source and part number?
 
If you search these forums for Conical Lord engine mount you will find the numbers. I think you have the correct part number.

NOTE: You can shim the engine mount to isolation mount to align engine.

In regards to to clocking of the spacer that will not effect the position of the spinner... You did not ask this but found this... I had conical engine mounts on my RV-4 long ago....

From the Forum..." I used the J-6230-1 mounts... the pin doesn't go on the engine case, but is a locator pin hole on the engine mount itself...Look on your engine mount and you (should) see a small hole next to the bolt hole on each pad... This is where the (1/8" dia. I believe) short pin goes in to orientate the Lord mount.. All 4 are in a different clock posistion... I used these on my 0-360 conical mount on my 6A... worked out great!
Sheldon"

What engine model do you have.
I assume you replaced all 4 isolators?
Do not use cheap plain jane rubber donuts with washers, use the LORD conical mount isolators.

Again search these forums for conical LORD to confirm number. There are two numbers but the one you Ref seems to be the correct one.
 
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Alignment update

Thanks for the reply!!!! With some shimming, all worked out. The ratio of spinner offset to shim thickness is very close to 4:1. Since we needed a 1" lateral deflection to the left on the spinner, we needed net 1/4" shim thickness on both right mounts (spinner was centered vertically). We got this by moving the thick AN970-8 washer from the front vibration isolator to the rear (engine mount) end and using the thinner original washer at the front (nut side). I believe that the A&P had to grind the OD of at least one of the AN970-8s to get it to fit. Also had to add a Lowes 0.050" thick x 1/2" ID x 2"OD fender washer next to the engine mount to get the net 1/4" shim height on both right side mounts. We also had to grind the AN310-8 nut so that the cotter pin could be installed.... we'll install longer AN8-54 bolts and new AN310-8 nuts ASAP. We might also add one more Loves washer to each right side mount, as another 0.200" deflection should put the spinner spot on with the original position. Hopefully, this helps someone else!

By the way, our engine was originally and O-320 that was stroked to an O-360....my situation may be quite unique, but the shimming tip (4:1 ratio) should apply universally to any RV4
 
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