The Problem Returns

[Brady Longmore]

I recently posted about some play in my clutch bell assembly, and that I thought I had figured out the problem and fixed it. Turns out, after flying yesterday that I was wrong. I still have some wiggle.

I completely removed the clutch assembly today, and noticed what might be causing the slop.

It seems to me that the slop is being caused by the loose fit of the delrin bushings into the clutch itself. How snug are those bushings supposed to fit into the holes in the clutch? Do those bushings wear down over time and need to be replaced once and a while? Could my last crash have caused them to be suddenly shaved down in diameter? I have literally only had about 2.5 gallons of fuel through this heli.

I checked the bushing bolts and they are tight. While in flight there is no noticeable problem. I'm guessing the centrifugal force, and the act of the clutch engaging the clutch bell might be counteracting the slop.

I dunno. Any ideas?

[Piton]

I have literally only had about 2.5 gallons of fuel through this heli.



That's your first problem. :wink: Get out there and fly that pig!

[Brady Longmore]

yeah, no kidding. That's what I'm trying to do anyway. :oops:

[cbergen]

Do those bushings wear down over time and need to be replaced once and a while?

Well, yes and no. Under normal use, not really. If you have a misalignment between the fan hub and clutch, then the constant up and down motion can and will wear down the bushings.

Typically (especially lately) the delrin bushing are pretty tight going into the clutch.

[kelly steed]

I'M not understading this.With the bell installed in the triple bearing block and the clutch assy put thought the clutch bell with the shaft thought the triple bearing block with the collar installed on the top of the tripple block there should be no side to side movment or up and down movment from the clucth bell.So if you hang on to the tripple bearing block with one hand and use the other hand to try to move the clutch bell assy and theres movment stop right there.check this frist then we will talk more on your bushing and alinment.

[Brady Longmore]

Kelly,

Thanks for the help. I tried your test, and the bearing block is solid. Bolts are tight, and no movement from the bearing block. When I wiggle the clutch bell, the movement translates all the way to the top of the clutch output shaft. I wonder if I need to replace the bearings in the bearing block. Although they seemed to spin fine on the shaft without any problems when I had it all apart. And, after reassembling it all, the up and down movement is gone. But, now I can wiggle it maybe 1/8th of an inch in any direction. Maybe less. Pretty minimal actually.

[kelly steed]

Your right you need to replace all three bearing in the bearing block,when you get you bearings make sure the bearing that sits on the gear,that the inner race fits fairly snug.make sure you gease the bearings if you have a greaser.when installing bearing if you need to tap them in,tap on the outer race only.you can try that bearing that you have to see how the inner race fits on that shaft above the gear,hopfully not to bad,sounds like you had some alinment proplems.You better order two new bushings and steel insert for your fan hub.If your alingment was bad from the start you might need a new gear for your clutch bell,for the reaseson that the shaft above the gear is badly warn.when installing new bushing make sure you follow the instructions from bergen.eg using the clutch for alingment,small amount of lock tight,steel inserts facing the right way.and when your done the derlin bushing should spin freely.When you get your clutch,bell,tripple bearing block to gether if its done right thier is no movment at,I mean none tight only.

[kelly steed]

brad if you have any proplems with any of the above steps pm me.then I wil take you though the alinment steps.

[kelly steed]

I forgot smothing be sure to taper your collar on the top of the tripple bearing block so it rides on the inner race of the top bearing only.