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Discussion Topic:
Shim pack in 21 stud babbit main V-8
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ckh |
10-30-2013 @ 9:30 AM
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Member
Posts: 6
Joined: Oct 2013
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Thanks for your reply Tom. This gentleman was quite old when he did this work for me. Not sure if he is still living, but if I can find his number it's worth a try.
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ckh |
10-30-2013 @ 9:23 AM
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Member
Posts: 6
Joined: Oct 2013
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Thanks for your reply. The shim pack that I have is Federal-Mogul #1508M 1/64.
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TomO |
10-30-2013 @ 8:51 AM
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Senior
Posts: 7252
Joined: Oct 2009
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I would try calling the man that poured the bearings. If he supplied the pack, he should have access to more.
Tom
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JerryW |
10-29-2013 @ 5:48 PM
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Member
Posts: 13
Joined: Aug 2010
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I have enclosed another picture of the block being line bored to accept cam bearings.
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JerryW |
10-29-2013 @ 5:46 PM
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Member
Posts: 13
Joined: Aug 2010
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NO shims were installed from the factory, therefore, there will be no part number. If it was line bored with shims in place they must be re-installed. Fortunately I have all the equipment for pouring bearings and line boring.Enclosed is a picture of a bearing being poured.
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ckh |
10-28-2013 @ 7:51 PM
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Member
Posts: 6
Joined: Oct 2013
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Thanks for your reply. I have used plastigage before and am familiar with its use. In reading my post again I should have said the entire shim pack on one side of the rear main cap is broken in half (next to the slinger), not just one shim. Any ideas where I might purchase another complete shim pack? Thanks again
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supereal |
10-28-2013 @ 12:18 PM
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Senior
Posts: 6819
Joined: Oct 2009
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Any good babbit repour should include shim packs. Using a product called "Plastigage", available at good parts dealers,you place the crank into the block, put a piece of the material between the crank and the caps, and tighten to spec. Then, remove the cap and compare the width of the plastic piece with the legend on the package to determine the clearance. If too wide, a shim is removed, and the process repeated until the clearance is correct.The shims are peeled from the pack, and unless the pack is damaged, or the clearance too tight, finding a replacement for the damaged shim may not be necessary. As to oil leaking from the rear main, the bearing clearance isn't the consideration. If you have an early block with a slinger, or a later type with a rope seal, it should be sufficient unless you overfill the oil pan. If you don't have a filter, install four quarts of oil. After you determine you have the correct clearance at all mains, apply some assembly lube before final assembly of the caps. this protects the bearing surface at startup, before the oil is fully circulated.
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ckh |
10-28-2013 @ 10:39 AM
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Member
Posts: 6
Joined: Oct 2013
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Does anyone have any experience or thoughts on the use of shim packs on the main bearings on a 21 stud babbit main block? The gentleman that poured the bearings in my block installed them. I haven't assembled the engine as yet and am having second thoughts about their use. I am concerned about oil leaking from the rear main into the clutch/flywheel area. Regardless, one of the shims for the rear main cap is broken and I will have to find a replacement should I decide to use them. It would probably be difficult to find. Would it be possible to remove the shim packs and re-align bore the bearings or would re-pouring the bearings be required? Would appreciate anyone's thoughts on this, especially experienced engine builders. Thanks
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