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| | | | Joined: Jan 2022 Posts: 2,492 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,492 | I need a tool to properly seat the rear main oil seal in a GMC 302 engine. I have a trashed crankshaft from a GMC 228 that uses the same bearings. I do not have, nor do I know how to drive an oxy-acetylene torch. Does it make sense to find someone local to lop off the rear bearing portion of the crank to use as a tool? GMC Maintenance Manual shows a picture of a "mandrel" to do the job, but doesn't list specs or a Kent-Moore part number.
Or should I try to find someone with a wood turning lathe to make such a tool?
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
| | | | | Joined: Feb 2004 Posts: 29,875 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,875 | Aluminum is much easier to work with than steel, and much more durable than wood. Give me a good diameter and width measurement of the seal surface on the crankshaft, and I can whittle one out on the lathe in about an hour. I made a rope seal seating tool for John's 261 from an old piston.
Jerry
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| | | | | Joined: Dec 2018 Posts: 2,450 'Bolter | | 'Bolter Joined: Dec 2018 Posts: 2,450 | Bill Hanlon That aluminum offer sounds best but your local welding shop could cut it or find a metal chop saw or get a cut-off wheel for your hand grinder. | | | | | Joined: Feb 2000 Posts: 5,236 'Bolter | | 'Bolter Joined: Feb 2000 Posts: 5,236 | A large socket rolled over the seal works pretty good. Heres how I assemble Pontiac's, they use a two piece rope seal, I install the one piece of the seal in the block leaving it long, drop in the crank, and use a block of wood to tap the crank down into the seal till the crank hits the bearing. I then remove the crank, pull the seal, install the second piece and repeat. The first piece is installed in the cap and trimmed to length. The second piece is then trimmed, and ready to use. The real key to rope seals is using https://bestgasket.com/rear-main-seals/ brand seals if available for the engine. They are a far better seal then what comes in gasket kits.
Last edited by Joe H; 06/27/2023 12:38 PM.
| | | | | Joined: Dec 2018 Posts: 2,450 'Bolter | | 'Bolter Joined: Dec 2018 Posts: 2,450 | Joe H That sounds like a good method,of the 87 offerings from Best it seems like something there would work !! When I put in -.002 main bearings I just spun the rear main right on in there torqued it slappedd on a fresh pan set,clean pan and went to truckin,is fine after 12,000 miles. I think PCV helps that a lot.Also helps to seal the cap parting line with something the torque -up can squeeze out of there,however I didn't that time. Had the tranny back so the shaft could fall down out of the way. | | |
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