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  1. #1

    Default Mercruiser 120 manifolds?

    I was wondering if anyone knows the difference between the two manifolds that go on the 120. I know the larger one will also fit the 140's. But is one better than the other? Do they interchange on the head? I've got both available for my project, and I want to do this right. Also is it worth it to put in the oil change kit?

  2. #2
    Moderator Bond-o's Avatar
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    Default Re: Mercruiser 120 manifolds?

    Quote Originally Posted by trihullk72 View Post
    I was wondering if anyone knows the difference between the two manifolds that go on the 120. I know the larger one will also fit the 140's. But is one better than the other? Do they interchange on the head? I've got both available for my project, and I want to do this right. Also is it worth it to put in the oil change kit?
    Ayuh,... Which 2 manifolds,..??

    There's been Many over the years....

    Yes to the oil change hose...
    Any Grease is Better,..... Than No Grease at All.......

  3. #3

    Default Re: Mercruiser 120 manifolds?

    I've got one that through bolts to the head with a bigger exhaust elbow and the carb bolts directly. And another that bolts just through the flanges so there is no exposed bolts when looking from the port side, and has a small manifold for the carb. Both carbs are rochesters J2 with ever so slight differences. I figured the oil hose was a good idea, just havent seen one yet. thanks for the confirmation.

  4. #4
    Moderator Bond-o's Avatar
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    Default Re: Mercruiser 120 manifolds?

    Quote Originally Posted by trihullk72 View Post
    I've got one that through bolts to the head with a bigger exhaust elbow and the carb bolts directly. And another that bolts just through the flanges so there is no exposed bolts when looking from the port side, and has a small manifold for the carb. Both carbs are rochesters J2 with ever so slight differences. I figured the oil hose was a good idea, just havent seen one yet. thanks for the confirmation.
    Ayuh,.... The head port alignment is the same for all the heads, for boltin' the manifold on...

    So long as the riser aligns with the downpipe, ya can probably use either 1...

    Pictures would help...

    yer base plug should be 1/2"- 20, so you'll need the drain kit to match...
    Any Grease is Better,..... Than No Grease at All.......

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