Rocker pivot stud sheared off, what might this indicate?

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Doodleboink
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Rocker pivot stud sheared off, what might this indicate?

Post by Doodleboink »

Hello chaps,

Had the bus for a month now, not used a great deal, but when we have used her, she's been mighty tappety. I got round to removing the rocker covers over the weekend to reset the tappet clearance adjusters. No2 intake tappet lock nut had shaken loose so, by this time, the adjust had shaken almost all the way out. Initially I though 'aha! sussed it!', but further poking around revealed that the actually rocker pivot shaft wasn't actually fixed in position. The stud the exhaust side came out no problem, but the intake side stud had sheared in the head. It had been like this since we got her and as neither of us had heard many VW engines up close, we just thought a good flush would probably solve it.

Anyway, I managed to get the sheared 1/2" of thread out of the head and I've ordered another, but my main concern is that something else caused the bolt to shear, tho I am hoping the previous owner just over torqued it and once the parts were hot ripped the stud in 2. What do you reckon? Put it back together and it'll be reet or is there a bigger nightmare lurking within?

Thanks.

E D I T: Oh yeah, 2l CU Aircooled. :oops:
Last edited by Doodleboink on 12 Dec 2006, 15:01, edited 1 time in total.

SteveW
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Post by SteveW »

I think that the nut may have come loose at some point. So the rocker shaft rattling about has sheared the stud. Put the new one in thread lock it all up and all hopfully will be fine.
Never enough time

Doodleboink
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Post by Doodleboink »

Cool! :ok

It was just as JK stock them, I thought maybe they go when something else happens. Funny I couldn't find owt on here and JK only list them for splittys and bays, but not Bricks, even tho they're the same part. Maybe they're more prone to go on older ones or something.

SteveW
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Post by SteveW »

I would have thought you could get one cheap enough from VAG or what about Simon at the Brick Werks he is not far from you. having said that if you have ordered one from JK you should get it for the weekend.

Good luck and let us know how you get on. 8)
Never enough time

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Dan Wood
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Re: Rocker pivot stud sheared off, what might this indicate?

Post by Dan Wood »

Doodleboink wrote:The stud the exhaust side came out no problem, but the intake side stud had sheared in the head. It had been like this since we got her and as neither of us had heard many VW engines up close, we just thought a good flush would probably solve it.

I'm glad to hear that. I had been feeling stupid about thinking my tappets were noisy when I had this problem too!

I'm not 100% sure, but my noise started at about the same time my throttle stuck fully open during a gear change. I don't have a rev-limited rotor arm either, so I dread to think what rpm the engine did!

Anyway, since getting a new non-sticky throttle cable, and getting Mr. Baxter to fix the stripped stud the problem hasn't come back...

(Yet:) )

Doodleboink
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Post by Doodleboink »

Thanks for all the advice. I'll have a crack at the weekend and see how she goes.

Doodleboink
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Post by Doodleboink »

Yep, everything refitted and working loads better. Bit of crap at first, but cleared and running loads better now.

I'm still having fun working out what all the wires etc do/aren't doing. I seem to have a centrifugal advance only distributor and I'm sure some wires aren't connected that should be. I've yet to find a decent piccy tho so at some point I'll have to post a pic for someone to break down.

And.... where the hell is my damn timing mark! I have searched and searched (on the pulley), but can't find owt. I have the mark on the dizzy, but no mark near the timing scale.

Why do JK do an ignition bundle, inc non-vac dizz, if it isn't suitable then? Or is the pic not accurate?

SteveW
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Post by SteveW »

I think that you may have the wrong dizzey. Is it a 009 with points?
PM your e-mail I have a file that may help you.
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Doodleboink
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Post by Doodleboink »

Why oh why did I not use thread lock? :roll:

M5 to Worcester Sunday afternoon. Bit of a funny rattle from engine, pull over to take a butchers, knowing I'd adjusted tappets that morning. (they were over tight, meaning holding valves open once warm.) No.2 cylinder had shaken loose the rocker shaft stud nut on one side and rattled the other shaft stud free too. The noise was pushrods meeting rocker cover. :shock:
I do recall the noise of a tiny metallic object hitting the deck when I'd taken the rocker cover off that morning, so I guess that was the nut and I just missed it's absence while I was poking around. Anyway, this nut's done a runner and I need a replacement. I know it's 11mm wide but what thread is it? What size will fit? I'll make damned sure it's all thread locked in this time, but would another nut on top of the first offer any extra rattle proofing? Or just another risk to fall down a push rod tube?

Thanks.


(correct dizzy obtained, fitted, and (was) running like a charm BTW)

Doodleboink
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Post by Doodleboink »

Rait, picked up what we thought were a direct replacement and stainless ones for good measure too at Dubfreeze, but they're just slightly too big. Can anyone confirm that these are M7s? The ones I got are M8s and it's only a knat's whisker out.

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toomanytoys
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Post by toomanytoys »

Have you got hydraulic tappets?
if so, do not do the procedure in the haynes.. only do them 1/2 to 1 turn from just touching...
Dont know about the nuts.. but prob a god idea to get some nuts from VW etc....

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murdoch
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Post by murdoch »

mine were M7 too, had a local machine shop make me up a few, only cost a fiver
murdoch

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