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Flywheel versus pilot bush

Soup

Jedi Hopeful
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About a week ago this topic came up. I'm presently doing my clutch and noticed that the pilot bush fell out of the flywheel during removal, no big deal. But now I go and place the new pilot bush into the flywheel, as dry fit before having it resurfaced, and it just falls into place. No force or pressure of any kind needed. There doesn't appear to be any play in the pilot bush when it is in place but from what I recall the pilot bush should require some effort to get it set into the flywheel. Could this mean I need a new flywheel??
 
I don't think it should fall out. Make sure you've got the right bush.

The problem should not be the flywheel. On my TR4A, the bush can't even fall out because the flywheel opening is smaller than the hole in the crankshaft. I'd think the TR6 is the same.

All that from someone who just replaced a clutch, but warning: I'm no expert.
 
Soup,
I went throught the same thing this past week. The old PB fell out the engine side of the flywheel and the new one fell right in. If it came out from the trans side, something is not right. There is a lip on the trans side to trap the PB between the flywheel and crankshaft. I thought this was odd, and since I had another new PB from another vendor, I tried it. It also slid right in. I went ahead and used what I had. The old PB was slightly out of round where the input shaft engages.
As an added note: If you have access to a lathe, you may want to consider removing the front cover of the trans and polishing the wear surface to 800 grit. Mine had some minor scuffing and scratching from the "Green" TOB. It is much cheaper than a new cover. As sensitive as the clutch can be, I thought it was worth the extra time to eliminate all possible problems.

Gordo
 
Gordo, does your new clutch squeal at all? That is what I assume could be the only down fall of not having a pressure fit because the PB could rotate with the flywheel. It can't fall out because of the lip on the outter edge of the FW.

Other than a possible squeal, could there be another problem that might arise from the PB not being a pressure fit?
 
I just did this two days ago with Fidenza alloy flywheel.

The pilot bush fit snugly and required a light tap from a rubber mallet to go in. From what I've read you should NOT have to press the bush in.
 
The P.B.s I have done in the past have not exactly been a pressed fit, but didnt "fall" in either It should be a snug fit {no sloping around} IF this is the case, I would say it will be fine to use.
Its purpose is to keep the trans main shaft aligned and thats about it.
There should be very little if any play between it and the flywheel or crankshaft P.B. counterbore and the same goes for where the trans mainshaft goes through the P.B. It needs to spin freely on the mainshaft.
Myself, IF I thought it too loose in the flywheel {depending on how loose} I MIGHT go as far as to place three equaly spaced center punch marks on the bushing to ensure a snug fit.
NOTE:
Dont hit it too hard as to distort its round shape
 
My PB is from TRF and it sounds like I'll be ok. There isn't any play between the The PB and stock flywheel. It fits without any play, it's just that it fits in rather simply, no tap required.

Still wondering though, does anybody think it will spin in the Flywheel and cause a squeal? Maybe just a chance I take.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]the pilot bush should require some effort to get it set into the flywheel. [/QUOTE]

According to Bentley, pg 111

"Fit the spigot bush into the back of the flywheel ensuring that it is a loose fit."

I would apply lubricant to both bearing surfaces and slide it in.
 
I guess "fell in" was "too loose" a turn. Lame attempt at humor! The PB slid in nicely with maybe .002 clearance. I found no need to tap.
I drove the car today and was pleased I had no squeel from the TOB or PB. I used the Gunst/Luk, so I was a little concerned but after 50 or so mles, no difficulties yet.

Gordo
 
With the Luk and the Gunst, you should be OK. Never use Gunst and Borg and Beck. Please don't ask me how expensively I know that to be true.
 
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