First Generation Firebird
Posted By: Lupdiesel Correct Rod to Crank Placement - 09/18/12 11:28 PM
I know there's always some confusion about correct cylinder numbers and this can lead to incorrect connecting rod placement on the crank during a rebuild. I know Kelly (medhat68) had this issue and was documented on his web site. http://www3.telus.net/public/68bird/engine_mistake.htm I too had problems with cylinder numbers since I was always told #1 cylinder is the most forward facing cylinder. Whoever told me that wasn't a pontiac guy. #1 cylinder is the driver's front (eventhough it's not the forward most cylinder).
After installing my new rod bearings, I was able to correctly see by the bearings the correct placement. The attached photos clearly show an offset of the bearings to make room for the radius fillet on the crankshaft. This offset goes against the crank and the other side goes against the other rod.






These second round of pics show the offset with the crankshaft. You can see the correct and incorrect placement. The offset toward the crank radius. First is correct.



This is incorrect







Kelly’s web site has some photos of his mistake but I thought these would be more detailed. Kelly was able to help me out and I want to pass it on as well.
--Kyle
Posted By: medhat68 Re: Correct Rod to Crank Placement - 09/19/12 01:57 AM
those are some great pictures all right. Thanks Kyle. And yes I sure did add a link to this page from the"mistake" page on my site.
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