I have a 1989 YJ, 4.2, 209,000 n change on motor.
I found a nice rebuild able 1986 4.2.
Vin number on the '86 block says it was built April 24, 1986.
This '86 motor has the PLASTIC valve cover, BUT, no center bolts on the rockers to hold it down, but the other hold down bolts are for a plastic cover.
My '89 motor has a " fresh" low mileage cylinder head PO installed. With a Almn valve cover.
I see all the head and intake/ exhaust gaskets for both engines are the same.
Head bolts are not,( '86 has 1/2-13 by 3"), ('89 head bolts are 7/16").
I've read,( on line), some say yes, others, no way??????
Can the '89 head fit on this '86 block with the '86 head bolts??
Here's a bit more info.
For sheets n giggles, I looked on Auto Zone web site for remain heads.
Both heads have same SKU numbers?
I'm THINKIN that if I used the '86 head bolts, it should?? work???
Joe
I found a nice rebuild able 1986 4.2.
Vin number on the '86 block says it was built April 24, 1986.
This '86 motor has the PLASTIC valve cover, BUT, no center bolts on the rockers to hold it down, but the other hold down bolts are for a plastic cover.
My '89 motor has a " fresh" low mileage cylinder head PO installed. With a Almn valve cover.
I see all the head and intake/ exhaust gaskets for both engines are the same.
Head bolts are not,( '86 has 1/2-13 by 3"), ('89 head bolts are 7/16").
I've read,( on line), some say yes, others, no way??????
Can the '89 head fit on this '86 block with the '86 head bolts??
Here's a bit more info.
For sheets n giggles, I looked on Auto Zone web site for remain heads.
Both heads have same SKU numbers?
I'm THINKIN that if I used the '86 head bolts, it should?? work???
Joe
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