Prop extension lugs loose

[southtarnation]

I have two loose prop lugs on my extension. I spoke to Sam Saber and he ran through a procedure I didn't really grasp. Before I call him back I was hoping to learn from the knowledge base here.

He suggested "steaking" the lugs and ??? Using a drive pin to spread the top 50% and then a 3/8ths all thread (since I have 7/16 prop bolts) with a nut and washer on the back and a socket on the front to draw it back into the extension whilst using wd40 liberally.

Hopefully someone can help me clear up my notes so I can call him back and have an idea what he his telling me to do.

 

[Mike S]

I believe he is referring to forcing a tapered tool to into the bushing, which will expand the outer diameter of the bushing. Just dont over do it.

The all thread and socket will form a arbor press like setup, will pull the bushing into the prop flange. The socket is to give a cavity for the bushing to go into as it comes through the flange, otherwise it would stop flush with the face of the flange.

Here is a shot of using the same technique to install bushings in the spring eye of my Jeep project.

In your case, the prop flange is the spring eye, and the socket will replace the lower steel plates.

 

[BillL]

I don't think so Mike, It seems to me like he wants the loose lugs removed, then use some tool to compress just outside the perimeter of the lug hole in order to squeeze the lug bore walls to a smaller diameter. Then use a solid dowel pin of the exact diameter to drive into that smaller hole to resize the upper half. Then use ample lubricant as you re-press the hollow lug fully to the bottom of the hole. This tightens the bore back up.

No having said that, the loosey goosey part is the staking process and what he would recommend there.

For example the valve seats in contintenial heads are "staked" with aluminum displaced so it overlaps the top . . . so when they come loose they won't come out of the head!

It would seem to me that this staking will need some skill and guidance, more than has apparently been conveyed to us. I would do it with a lathe turned tool and in a hydraulic press. Maybe an all thread would work, but it should not be done in one pass as the amount of material displacement is unknown vs torque on the all thread.

Added: This is a bit shade tree, but could be easier. :: One might be able to take a sturdy center punch and round off the end so it is maybe 3/16 in diameter, then radius the working face with at 1/4" or a low crown. This could be worked (smashed with a heavy hammer) around the outer perimeter of the lug bore (lug out) a little away (3/32?) from the edge and use overlapping positioning to achieve the staking. Don't hit it too hard in the beginning. The aluminum spacer/extension will be yielded and displaced to shrink the bore. Honestly, I think I would do it this way and test the lug until it was snug then hammer a little more then just press the lug in. It would be safer than driving some pin in place to resize the bore.

 

[southtarnation]

Thanks for the tips.

I could be wrong but I am pretty sure Sam wants me to remove the lugs and spread the lug out down to the shoulder of the lug in some way and then use a method similar to what Mikes pictures show to reinstall the resized lug(s) rather than resizing the hole in the extension. I think I grasp how to install the resized lug without damage I am just still unclear on a method and tool to use to spread it and how it should be staked.

 

[Mike S]

I am just still unclear on a method and tool to use to spread it and how it should be staked.

Probably best if you contact Sabre and ask for clarification then.

I would suspect he will tell you to use a drift punch that is the right size to fit inside the bushing, but will still not go all the way through, you then use the taper of the drift to expand the bushing-----------but then that is only my best guess..............

 

[BillL]

Probably best if you contact Sabre and ask for clarification then.

I would suspect he will tell you to use a drift punch that is the right size to fit inside the bushing, but will still not go all the way through, you then use the taper of the drift to expand the bushing-----------but then that is only my best guess..............

That would certainly work, but yes, I fully agree, Sam is the one to talk to. Maybe he is asking to expand the lug, but I can not visualize what staking has to do with the process of expansion. I have never heard staking used except as a metal displacement process.

Let us know what you find, I need to learn a few things each day.