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Discussion Starter · #1 ·
As im replacing the head gasket, i noticed that the head gasket dowell holes do not fit over the front left and back right dowell. Attached are pictures of the dowell not fitting into the holes in the head. Its only those two holes that are too small in each corner. Did the manufacturer not drill the hole large enough? Or does it need to be forced on?
 

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first thought flip gasket over left to right..
yes,, two holes should be larger,, if holes are all the same size, manufacturer error I would say..
 

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Discussion Starter · #3 ·
first thought flip gasket over left to right..
yes,, two holes should be larger,, if holes are all the same size, manufacturer error I would say..
wait, are you saying that two holes should be larger and two should be smaller? Thats how it is but i just dont understand why it doesnt fit right. I have the dowels in the right place but it just seems two of the gasket holes are too small. Is it supposed to be like that?
 

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I'm saying 2 holes diagonally from one another on outside studs (left forward and right rear of cylinders iirc) should be larger than the other 9 holes..

Looking closely at your gasket images are you sure that it isn't the case to cylinder gasket, the tab off to right makes me think this is a cylinder gasket and not a head gasket...
 

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Discussion Starter · #5 ·
I'm saying 2 holes diagonally from one another on outside studs (left forward and right rear of cylinders iirc) should be larger than the other 9 holes..

Looking closely at your gasket images are you sure that it isn't the case to cylinder gasket, the tab off to right makes me think this is a cylinder gasket and not a head gasket...
im pretty sure its the headgasket bc the cylinder gasket looks different. I ordered two head gaskets one is chinese and from ebay and one is from babbitts. They both look the same. I just feel like im forcing this gasket onto the cylinders bc the dowels dont fit in the hole... i guess its supposed to be like that?
 

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I see that what you have shown wouldn't work as a case to cylinder gasket..
yes they are quite different..

1st gen uses 4 dowels and 3 additional (o-ring type) seals in addition to head gasket..
so our perspectives are a bit different.
 

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I am assuming dowels don't fit in opposing holes I circled..
 

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extra sealing is done at those two points as well as one other stud on 1st gen..
I wouldn't enlarge.. if it doesn't seal properly fault is makers..
once modified you earn the blame for failure.....

do you have remnants of old gasket to compare?
 

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Discussion Starter · #11 ·
extra sealing is done at those two points as well as one other stud on 1st gen..
I wouldn't enlarge.. if it doesn't seal properly fault is makers..
once modified you earn the blame for failure.....

do you have remnants of old gasket to compare?
true. Ill probably just put it on as normal. I threw it away but am trying to find it in my trash can haha. Good idea. Thanks
 

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Discussion Starter · #12 ·
So the company I purchased it from contacted Honda about it. Honda updated the head gaskets because the old ones contained asbestos. With those updates, they made two of the holes smaller, and you dispose of two of the dowel pins.
 

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Thanks for getting to the bottom of this. Gonna tag this so others can find it.
 

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So the company I purchased it from contacted Honda about it. Honda updated the head gaskets because the old ones contained asbestos. With those updates, they made two of the holes smaller, and you dispose of two of the dowel pins.
Does it matter which ones you ignore? I want to assume that it's a good idea to keep the pair that both have the o-ring type gaskets around the dowels.
 

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Does it matter which ones you ignore? I want to assume that it's a good idea to keep the pair that both have the o-ring type gaskets around the dowels.
I don't have an definitive answer, But would likely go with the o-ring pair myself..
 

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Hi all, was there any further information on this as I am currently in the same situation - I've been supplied genuine Honda headgasket part number 12251-KBG-671 as the only gasket now available and my engine has the 4 dowels and 3 o-rings

Has anyone successfully used this gasket and did they discard the two dowels and 3 o-rings?
 

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@Dan4 I'll refer you to this post:
 
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