dalewalt Posted March 16, 2021 Report Share Posted March 16, 2021 Hi all, I've started rebuilding my engine for my '40 Plymouth P10. I tore the engine down (following a thread I found in this forum) and cleaned/degreased everything. I'm reusing the old crankshaft, but bought a new camshaft/pistons/rods/bearings/valves/etc. The steps I originally took was: Install old crankshaft w/new bearings (standard size) install new pistons/rods/bearings I then found I couldn't turn the crankshaft, even with a breaker bar on the end of the crank. Oops... better check bearing clearances. I disassembled everything and measured crank bearing clearance (.002, as expected). But when I reinstalled the crank and torqued to 75 ft.lbs., I find that I can only turn the crank if I put a breaker bar on the end. Is this how it should be? Or should I be able to turn just by grabbing the timing gear. (I haven't yet installed flywheel/timing/pistons/etc) Once I install the pistons, I'll check the bearing clearance on the rods. But once rods/timing/etc is installed, should I still be able to turn the crank w/a breaker? Thanks for any help/advice. Dale Quote Link to comment Share on other sites More sharing options...
Sniper Posted March 16, 2021 Report Share Posted March 16, 2021 Check for anything on the back side of the bearing shells. Clean them well anyway. then install the crank, spin test it without torqueing the mains, just hand tight. then torque them one at a time and spin test after each one is torqued. This will tell you the one that is the problem. Did you check the thrust clearances too? 2 Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted March 16, 2021 Report Share Posted March 16, 2021 be sure you do not have a bearing cap out of order....... 2 Quote Link to comment Share on other sites More sharing options...
knuckleharley Posted March 17, 2021 Report Share Posted March 17, 2021 (edited) 42 minutes ago, Plymouthy Adams said: be sure you do not have a bearing cap out of order....... Yup,and if you have two that are tight,swap them for one another and try again. Make sure you stamp all your bearing caps with numbers once you get it straightened out. Edited March 17, 2021 by knuckleharley 1 Quote Link to comment Share on other sites More sharing options...
squirebill Posted March 17, 2021 Report Share Posted March 17, 2021 I would recommend billrigsby assembly list found under "Downloads" of this forum(see top of page). Go to Downloads, then to "What's New"....hit the side arrow once and it is the first item on the second page. Regards Quote Link to comment Share on other sites More sharing options...
RobertKB Posted March 17, 2021 Report Share Posted March 17, 2021 You should never need a breaker bar to turn it. You will score something for sure. If you can’t turn it with a breaker bar, not much chance your starter will. Did you number rod caps and main caps when you disassembled? It’s vital they go back in the right order. Are you using assembly lube upon reassembly? Also, assuming your crank is ok as it sounds like it wasn’t machined. Also, I wouldn’t install pistons until crank turns easily in the mains. Lots to think about and the members on this forum are very helpful. There are no dumb questions, only dumb mistakes because a question wasn’t asked. Quote Link to comment Share on other sites More sharing options...
Hamilton Posted March 17, 2021 Report Share Posted March 17, 2021 3 minutes ago, RobertKB said: Snip: You should never need a breaker bar to turn it. Absolutely true - particularly given that you've yet to install the rods and pistons. As it sits, your crank should spin quite freely. _ Quote Link to comment Share on other sites More sharing options...
dalewalt Posted March 17, 2021 Author Report Share Posted March 17, 2021 (edited) Well, a bit more info. I checked the positioning of the caps as suggested, they're in the correct position. (Honestly, I don't think they could be out of position... I have four caps... they're all slightly different widths). So then I loosened each cap in turn and discovered that the cap with the oil tubes is the problem. When I pulled the cap off; I found a crack in the base of the cap. I put pliers on it and pulled away part of the cap: I think what was happening was that. since the base was cracked... when I torqued it, it was tightening down too much. So, I think I need a new bearing cap (this is the one w/the oil line attached). Does anybody know where I can find one? Does either Kanter or Andy Bernbaum carry them? Thank you much to everybody for all of your help (and thanks squirebill for the heads up on the checklist... that'll be very helpful) Edited March 17, 2021 by dalewalt Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted March 17, 2021 Report Share Posted March 17, 2021 using another bearing cap will require you to do an align bore.....whatever picture/link you posted...it is a postage stamp on display.... Quote Link to comment Share on other sites More sharing options...
dalewalt Posted March 17, 2021 Author Report Share Posted March 17, 2021 8 hours ago, Plymouthy Adams said: whatever picture/link you posted...it is a postage stamp on display.... Ugh, sorry about that. It shows the base of the bearing cap with a chunk missing Quote Link to comment Share on other sites More sharing options...
Sniper Posted March 17, 2021 Report Share Posted March 17, 2021 22 minutes ago, dalewalt said: Ugh, sorry about that. It shows the base of the bearing cap with a chunk missing Looked fine on my laptop Quote Link to comment Share on other sites More sharing options...
Dartgame Posted March 17, 2021 Report Share Posted March 17, 2021 Which engine are you working on ? 201 ? Quote Link to comment Share on other sites More sharing options...
dalewalt Posted March 17, 2021 Author Report Share Posted March 17, 2021 1 hour ago, Dartgame said: Which engine are you working on ? 201 ? I *think* it is... how would I tell for sure? Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted March 17, 2021 Report Share Posted March 17, 2021 without measuring you have the engineering code on your block...resource this number first.... Quote Link to comment Share on other sites More sharing options...
Dodgeb4ya Posted March 17, 2021 Report Share Posted March 17, 2021 I wonder how you cracked that main cap? You are in a tough spot now. Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted March 17, 2021 Report Share Posted March 17, 2021 I can spell out two scenarios..... Quote Link to comment Share on other sites More sharing options...
dalewalt Posted March 17, 2021 Author Report Share Posted March 17, 2021 2 hours ago, dalewalt said: I *think* it is... how would I tell for sure? Dartgame, yes, it's the 201. (I verified w/the number on the side of the block) Quote Link to comment Share on other sites More sharing options...
kencombs Posted March 17, 2021 Report Share Posted March 17, 2021 I can't see the pic either. Just a little solid circle with a dash in the middle. Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted March 17, 2021 Report Share Posted March 17, 2021 17 minutes ago, kencombs said: I can't see the pic either. Just a little solid circle with a dash in the middle. dash in the middle....that is the postage stamp cancellation mark.... Quote Link to comment Share on other sites More sharing options...
Merle Coggins Posted March 17, 2021 Report Share Posted March 17, 2021 No picture for me either. Not on my computer or on my iPad. Quote Link to comment Share on other sites More sharing options...
dalewalt Posted March 18, 2021 Author Report Share Posted March 18, 2021 2 hours ago, Merle Coggins said: No picture for me either. Not on my computer or on my iPad. Huh. Let me try attaching it from my phone 1 1 Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted March 18, 2021 Report Share Posted March 18, 2021 page 141 shows a picture that could well be the very identical twin to this picture as it clearly states.... THIS IS WHAT MAY HAVE IF YOU DO NOT CORRECTLY IDENTIFY BOTH CENTER BEARING CAPS BEFORE REMOVING Quote Link to comment Share on other sites More sharing options...
dalewalt Posted March 18, 2021 Author Report Share Posted March 18, 2021 1 hour ago, Plymouthy Adams said: page 141 shows a picture that could well be the very identical twin to this picture as it clearly states.... THIS IS WHAT MAY HAVE IF YOU DO NOT CORRECTLY IDENTIFY BOTH CENTER BEARING CAPS BEFORE REMOVING There wasn't any issue with identifying which caps go where... Each of them only fits in one place. And the one that cracked has three oil line connection Quote Link to comment Share on other sites More sharing options...
Dodgeb4ya Posted March 18, 2021 Report Share Posted March 18, 2021 The caps have to be original block caps...placed in the OE factory location and then carefully tapped down into the block recess till bottomed. Then tighten the main cap bolts...back and forth in two to three stages while also making sure the crank still rotates using just your hand. Of course always using a micrometer/bore gage and knowing how to use them when starting to assemble a new or rebuilt engine. Poor mans way.... use plasti-gage to carefully check clearances. Never assume engine clearances will be just fine. Quote Link to comment Share on other sites More sharing options...
keithb7 Posted March 18, 2021 Report Share Posted March 18, 2021 (edited) @Dodgeb4ya, so if you mix up a cap or two, an align bore job can fix everything back to re-use? Like new again? I'm feeling a little paranoid about my caps. I did label them. But it would be like a bomb going off in my engine if 1 cap blew-out like the post above. Devastating. Edited March 18, 2021 by keithb7 Quote Link to comment Share on other sites More sharing options...
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