Author Topic: Refitting exhaust and stud for collars too short 🤔  (Read 768 times)

Offline billdn

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Refitting exhaust and stud for collars too short 🤔
« on: July 14, 2022, 01:57:52 PM »
Just in the throes of refitting exhaust and I'm finding that there is insufficient thread to secure the collar. The studs were removed because I had some blasting done to clean up engine.
The studs are 47mm long, as part manual says for F model.
The stud is screwed fully home in the head   but if I wind it out a bit the collar fits fine. The thread length on the stud is the same both ends, so it's not in wrong way round.
Should I just back out stud from head enough to secure collars then tighten?

Offline billdn

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Re: Refitting exhaust and stud for collars too short 🤔
« Reply #1 on: July 14, 2022, 02:34:26 PM »
Doh! Doh!
Thought I'd already removed gasket before blasting, obviously not.
Senior moment ...again!
I blame the heat here in Sussex 😅🤣

Offline Nurse Julie

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Re: Refitting exhaust and stud for collars too short 🤔
« Reply #2 on: July 14, 2022, 02:35:07 PM »
Are the exhaust collets fully seated Bill. If they aren't pushed in all the way, this gives the effect that the studs don't have enough thread to fit the collars.
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Offline Nurse Julie

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Re: Refitting exhaust and stud for collars too short 🤔
« Reply #3 on: July 14, 2022, 02:35:54 PM »
Doh! Doh!
Thought I'd already removed gasket before blasting, obviously not.
Senior moment ...again!
I blame the heat here in Sussex 😅🤣
😂😂😂😂😂😂
LINK TO MY EBAY PAGE. As many of you know already, I give 10% discount and do post at cost to forum members if you PM me direct.
https://www.ebay.co.uk/sch/julies9731/m.html?item=165142672569&rt=nc&_trksid=p2047675.m3561.l2562

LINK TO MY CB400/4 ENGINE STRIP / ASSESSMENT AND REBUILD...NOW COMPLETE
http://www.sohc.co.uk/index.php/topic,14049.msg112691/topicseen.html#new

Online McCabe-Thiele (Ted)

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Re: Refitting exhaust and stud for collars too short 🤔
« Reply #4 on: July 15, 2022, 08:21:52 AM »
Easy done when I stripped my cylinder head I initially thought they were part of the ports - one was a bit out of shape so then I realised they were gaskets.
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Offline taysidedragon

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Re: Refitting exhaust and stud for collars too short 🤔
« Reply #5 on: July 15, 2022, 11:48:47 AM »
When I stripped my engine down I found 2 gaskets fitted in each exhaust port! They must have been too lazy to pry the old ones out, or didn't see them. That explained why the exhaust collets had all been ground shorter. 🤨
Gareth

1977 CB400F
1965 T100SS

 

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