Valve Cover Threads Stripped!


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hcbx1047
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Valve Cover Threads Stripped!

Post by hcbx1047 »

After way too long putting things back together I finally get around to making sure everything is good with the valvetrain and put the cover back on. This is the first time I've had the cover off on this bike but when I put the fasteners in (I know there are four long inner ones and four shorter outer ones, and that the fastener should just be seated and lightly snugged). So FOUR of them decide to strip just as I notice any real resistance. Three on the front and one in the rear.

So, having read others who have stripped these, I see a few options:

1. Take off the offending cam caps and helicoil them, or
2. Replace the offending cam caps, as I have a bunch of 'spares', or
3. Try liquid metal and drill and retap.

Pro's and con's to each of these, but which technique would you guys see as the 'easiest' and 'best'. Or are there other options that I have?

I'm tempted to try helicoiling first but what's the chances of getting spare caps to properly align? thx in advance........

For the record I've put in thousands of fasteners into aluminum and these stripped waaaay easy. Cam cover didn't leak before though btw.

jnnngs
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Re: Valve Cover Threads Stripped!

Post by jnnngs »

Hi,

Helicoiling is the most straight forward way to go.

Cam caps and head are a matched pair - they are line bored together. So, if you do replace cam caps will need to check alignment / clearances are OK. Not worth the effort - just helicoil the ones you have.

Paul.

hcbx1047
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Re: Valve Cover Threads Stripped!

Post by hcbx1047 »

jnnngs wrote:Hi,

Helicoiling is the most straight forward way to go.

Cam caps and head are a matched pair - they are line bored together. So, if you do replace cam caps will need to check alignment / clearances are OK. Not worth the effort - just helicoil the ones you have.

Paul.
Thx!

hcbx1047
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Re: Valve Cover Threads Stripped!

Post by hcbx1047 »

Can you helicoil in place if one is careful with drilling and metal particles (like preparing if for surgery!)? I looked at some spare caps and only the center caps taking the taller bolts have oil galleys and they don't come through the cam cover holes. I'm a little mystified by the cam cover bolt holes though in that they don't appear to be blind holes but have what looks like significant space cast in at the bottom of their bores. That made me concerned but it looks like a false alarm.

jnnngs
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Re: Valve Cover Threads Stripped!

Post by jnnngs »

Hi,

Others may disagree, but removing one cam cap at a time should be OK - no need to remove the camshafts. So, remove one, helicoil, refit etc.

Easier to work on that way.

Paul.

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herdygerdy
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Re: Valve Cover Threads Stripped!

Post by herdygerdy »

And while you are at it, may be worth considering getting a set of genesound's very excellent replacement cam cap cover bolts, 2 per cam cap, 16 in total IIRC...

steve murdoch icoa #5322
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Re: Valve Cover Threads Stripped!

Post by steve murdoch icoa #5322 »

Thanks for the reminder, Tony.
Some more info on the bolts from Gene.
viewtopic.php?f=5&t=8998&p=69884#p69884

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wyly
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Re: Valve Cover Threads Stripped!

Post by wyly »

Until recently I never knew that the cam caps and head were a matched set(forum members set me straight), I'd bought a replacement head without the caps :oops: ... luckily I managed to get the matching caps from the same ebay seller...had I not the mechanic who is rebuilding the head said with some careful machine work my existing caps could be fitted to the new head but it's not the preferred way (doesn't always work)and involves extra costs...helicoil is the best way imo...

there was one cap bolt broken off in my new head :? I never checked the valve cover threads :( the same po could have over torqued and stripped those threads ...
CBX a work in progress, still improving...GS1150EFE completed and awaiting modifications.....RD350, remnants in boxes scattered throughout the garage

hcbx1047
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Re: Valve Cover Threads Stripped!

Post by hcbx1047 »

Thanks for the replies. For the record I helicoiled them in place after totally covering the head with plastic and isolating each hole as I worked on them. Vacuumed and used compressed air as I went to keep stray aluminum shavings clear. Cover is back on!

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