Author Topic: Advice on valve cover hole  (Read 601 times)

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Offline lparm

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Advice on valve cover hole
« on: November 07, 2018, 05:42:49 am »
I am restoring a 1978 K8 and found this hole in the valve cover under the breather cover.
Anyone seen this before? Should it be welded? replaced?

Offline slikwilli420

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Re: Advice on valve cover hole
« Reply #1 on: November 07, 2018, 05:56:43 am »
Thats how they are cast, nothing to worry about. The valvetrain breathes through that area, and with the breather cover on, you won't have any issues.
All you gotta do is do what you gotta do.

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Offline lparm

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Re: Advice on valve cover hole
« Reply #2 on: November 07, 2018, 06:56:50 am »
thats good news, thanks

Offline flybox1

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Re: Advice on valve cover hole
« Reply #3 on: November 07, 2018, 06:58:42 am »
Yep...its normal.
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Offline Motorcycle jones

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Re: Advice on valve cover hole
« Reply #4 on: November 07, 2018, 10:41:29 am »
That is the improved valve cover design .
The 1978 model had 22 such improvements over the earlier models.

Offline ekpent

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Re: Advice on valve cover hole
« Reply #5 on: November 07, 2018, 04:12:39 pm »
That is the improved valve cover design .
The 1978 model had 22 such improvements over the earlier models.
  Hey MJ. Is there a published list of those 22 changes somewhere to read ? This is not a call out or anything, it would just be fun to read up on all the differences since I don't do 750's later then 1976 generally as a rule.