Author Topic: Valve guide replacement help!  (Read 1176 times)

Offline corromant

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Valve guide replacement help!
« on: February 22, 2018, 03:47:57 PM »
Need to replace 3 exhaust valve guides, set about this today but had a disaster. Warmed the head up till it was nice & hot & had had the new guides in the freezer overnight, made a drift which is probably where I made the big mistake as I made it to drive the new guide on the flange, needless to say broke the flange.
So before I attempt again a little wisdom would be appreciated. I have remade the drift so that it now sits on a small shoulder a little above the flange, hopefully you can see this in the photo's & should I be using any lubricant to help the guide in, if so what.
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Thanks in advance
Conrad
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Offline Trigger

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Re: Valve guide replacement help!
« Reply #1 on: February 22, 2018, 04:03:12 PM »
You need another type of drift that goes inside the stem, heat the head to 180c to make it easy. These valve guides like to bend as you put them in. After they are home, grind the valve seats and skim the head.

Offline corromant

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Re: Valve guide replacement help!
« Reply #2 on: February 22, 2018, 04:45:23 PM »
Thanks trigger, so sounds as if I can re use the drift I made to knock the old ones out, should I use any lubricant or put them in dry?
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Offline corromant

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Re: Valve guide replacement help!
« Reply #3 on: February 22, 2018, 06:16:26 PM »
Can easily fit the head on my mill to skim it, how do I remove the dowel from the head, should it just pull out or is it shrunk in?
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Offline Trigger

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Re: Valve guide replacement help!
« Reply #4 on: February 22, 2018, 09:16:26 PM »
All dowels should just pull out but sometimes they don't. If it's stubborn, put a drill bit down the centre of the dowel, just a tad smaller than the dowel, heat it up and get mole grips on it. The drill bit inside saves it getting flattened by the grips.The valve guides, just put red rubber grease on the 'O' ring, that's usually all the lube that is needed to insert them.

Offline K2-K6

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Re: Valve guide replacement help!
« Reply #5 on: February 22, 2018, 09:59:29 PM »
A sentence with "red rubber grease" along with "insertion" and "lube" is going to set off that 400 Four owning rabble again with all the innuendo potential that entails. ;D

Offline Nurse Julie

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Re: Valve guide replacement help!
« Reply #6 on: February 22, 2018, 10:15:32 PM »
A sentence with "red rubber grease" along with "insertion" and "lube" is going to set off that 400 Four owning rabble again with all the innuendo potential that entails. ;D
Rabble, rabble, how dare you Sir ;D ;D ;D
If you need reminding Nigel us CB400/4 owners have the majority on here, so don't set us off, it could get nasty  :o :o
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

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Offline paul G

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Re: Valve guide replacement help!
« Reply #7 on: February 23, 2018, 10:04:51 AM »
A sentence with "red rubber grease" along with "insertion" and "lube" is going to set off that 400 Four owning rabble again with all the innuendo potential that entails. ;D
Rabble, rabble, how dare you Sir ;D ;D ;D
If you need reminding Nigel us CB400/4 owners have the majority on here, so don't set us off, it could get nasty  :o :o
What do I do now Julie I have one foot in each camp don't know who to support ;D might just have to sit on the fence.
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Offline Nurse Julie

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Re: Valve guide replacement help!
« Reply #8 on: February 23, 2018, 10:28:27 AM »
A sentence with "red rubber grease" along with "insertion" and "lube" is going to set off that 400 Four owning rabble again with all the innuendo potential that entails. ;D
Rabble, rabble, how dare you Sir ;D ;D ;D
If you need reminding Nigel us CB400/4 owners have the majority on here, so don't set us off, it could get nasty  :o :o
What do I do now Julie I have one foot in each camp don't know who to support ;D might just have to sit on the fence.
It is a problem Paul when your loyalties are divided. Just fence hop when it suits you, like I do  ;D
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

Offline Nurse Julie

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Re: Valve guide replacement help!
« Reply #9 on: February 23, 2018, 10:31:38 AM »
There's only more 400 owners on the site because they never went fast enough to get written off  :) :) :) :) :) :)

Ken, your comment almost gives you life time membership to the '400 Bitches Club' 😋😋😋😋😋
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

 

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