Author Topic: Omitting o-rings and knock pins with MLS Gasket on an F2  (Read 649 times)

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Offline Chad

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Omitting o-rings and knock pins with MLS Gasket on an F2
« on: September 14, 2014, 02:22:41 PM »
So I am doing a top-end rebuild on my F2. I got the gasket set from Cycle X with the MLS head gasket. Do I need to use the knock pins and the rubber seals that go around them, or does the MLS gasket omit the need for them?

The kit did not come with new knock pin seals/o-rings. Thanks for your help!
« Last Edit: September 15, 2014, 06:42:42 PM by Chad »

Offline Don R

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Re: Omitting o-rings and knock pins with MLS Gasket on an F2
« Reply #1 on: September 14, 2014, 05:15:38 PM »
 I believe the pins are there to locate things mechanically. I've seen discussion on the size of the holes where the seals go, not sure which ones you have.
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Omitting o-rings and knock pins with MLS Gasket on an F2
« Reply #2 on: September 14, 2014, 05:49:37 PM »
Why not use them? Honda felt they were necessary.
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Offline Stoli

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Re: Omitting o-rings and knock pins with MLS Gasket on an F2
« Reply #3 on: September 15, 2014, 04:52:00 AM »
I believe your questions are answered here:

http://forums.sohc4.net/index.php?topic=107040.0

The thread is for an F3 but I believe the same applies to your F2.
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Offline flybox1

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Re: Omitting o-rings and knock pins with MLS Gasket on an F2
« Reply #4 on: September 15, 2014, 07:24:47 AM »
I believe your questions are answered here:

http://forums.sohc4.net/index.php?topic=107040.0

The thread is for an F3 but I believe the same applies to your F2.
+1 to this ^
o-rings and knock pins are required.  cylinder stud packings are not....
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Offline Chad

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Re: Omitting o-rings and knock pins with MLS Gasket on an F2
« Reply #5 on: September 15, 2014, 06:37:43 PM »
So in Branden's leak free top end thread he said:

Quote
After a few emails to some of the more knowledgeable wrenches on the CB750 I came to the conclusion of leaving my knock pins out completely.


Apparently, installing the knockpins and rubbers were a Honda band aid to fix leaky head gaskets. There is a Service Bulletin around here someplace stating this. Cometic gaskets make some of the best head gaskets in the industry and they make there head gaskets to be installed without the knockpins and rubbers. Do what you want with the information. I left mine out.

I also called Cycle X to confirm this is true for their MLS head gaskets, and it is. You DO NOT need the put the knock pins in. There are two longer knock pins that are there just for aligning purposes (or at least that is what I was told). You can see in Branden's thread pics that he put those in, and Cycle X confirmed as well to put those in. All of the other shorter knock pins stay out.  ;)

Thanks for you help guys! I really appreciate it.
« Last Edit: September 15, 2014, 06:43:49 PM by Chad »