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230 crank won’t turn


TylerB46

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Hi I recently had my crankshaft turned, mains are .020 and rods are .030. I’ve got the crank back in the block with the new bearings installed, all the caps are in the right place, but if I even torque them all down just 30psi I cant budge the crank at all. 

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Just now, Radarsonwheels said:

Do you have mics and inside gauges? Definitely figure out if it’s one or all of the bearings causing then problem. 

Unfortunately I dont own a mic. I used plstigage and everything seemed to be in spec at either .001 or .0015

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And it won’t turn? You have oil on it right? Tighten them one at a time to try and find the problem and don’t force it if it isn’t smooth. With no pistons installed it should spin on the muddy side of freely depending on the oil you use. A thou or one and a half doesn’t leave any room for error tightness wise but should last a long time in a stock application?

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24 minutes ago, Radarsonwheels said:

And it won’t turn? You have oil on it right? Tighten them one at a time to try and find the problem and don’t force it if it isn’t smooth. With no pistons installed it should spin on the muddy side of freely depending on the oil you use. A thou or one and a half doesn’t leave any room for error tightness wise but should last a long time in a stock application?

The front cap will tighten all the way down to 85psi and still turn freely, but the middle 2 catch without tightening down much at all

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16 minutes ago, kencombs said:

Double check to make sure the main caps are facing the right way. 

I have, I took pics of them before my initial disassembly, and mine have notches that someone put in them in the past, and looking at my  pictures they’re installed correctly.

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You need to mike the main journals on the crank and also bolt on the main caps... torque them to 85 lbs and mike them with a bore gauge or mike and telescoping snap gauge.

Same on rods...and crank pin journals.

Make sure the bearing shells and bores have no debris or nicks, burrs.

Clearances on mains .0015 to .0025"... rods .001" to .0022".......001" per inch of journal size

That's a common range on machine work done on the flatheads I've read about and seen on mine over the years.

Factory was less.

If the clearances are close enough.... bent crank????.... you need to check crank for end play too....dial indicator or feeler gauge......004 to .005" or close.

 

Edited by Dodgeb4ya
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21 minutes ago, Dodgeb4ya said:

You need to mike the main journals on the crank and also bolt on the main caps... torque them to 85 lbs and mike them with a bore gauge or mike and telescoping snap gauge.

Same on rods...and crank pin journals.

Make sure the bearing shells and bores have no debris or nicks, burrs.

Clearances on mains .0015 to .0025"... rods .001" to .0022".......001" per inch of journal size

That's a common range on machine work done on the flatheads I've read about and seen on mine over the years.

Factory was less.

If the clearances are close enough.... bent crank????.... you need to check crank for end play too....dial indicator or feeler gauge......004 to .005" or close.

 

The crank just came from the machine shop, so hopefully they checked to see if it was warped. As far as miking goes, I don’t have one and I really don’t want to spend that kinda money on some tools I’ll only use once. And I’m not too sure how to check the end play, could you explain that a little for me? If all else fails I’m planning on taking the crank caps and bearings back to the machine shop and having them check everything again.

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Check this thread out and watch the guys video... shows checking rods/mains and end play.

http://p15-d24.com/topic/49209-chryslerplymouth-flat-head-rebuild/

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did the machine shop provide the bearing matched to the crank when ground or did you have to order these in yourself.....snap gauges are inexpensive and even if you use it but once, can be sold or traded for other things needed.  How well did the crank turn block inverted and laying on a half shell?  Anything obvious out of whack...

Edited by Plymouthy Adams
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Are you trying this with or without the rear main seal installed?  Rope seals can put a lot of drag on a crank and the closer to the seal you get the more likely to get that drag and maybe a lockup.  If you have them in, take them out and try again.  Check the backside of all the bearing shells.  They should all have the same thousandths markings.  Those notches in the block and main caps were put there by the factory.  There're used to keep the bearing shell from rotating and caps, when installed will have that notch on the same side of the block as the one in the block.

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4 hours ago, Plymouthy Adams said:

did the machine shop provide the bearing matched to the crank when ground or did you have to order these in yourself.....snap gauges are inexpensive and even if you use it but once, can be sold or traded for other things needed.  How well did the crank turn block inverted and laying on a half shell?  Anything obvious out of whack...

I had to order the gauges, and half shell the crank turned really easily.

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54 minutes ago, Dave72dt said:

Are you trying this with or without the rear main seal installed?  Rope seals can put a lot of drag on a crank and the closer to the seal you get the more likely to get that drag and maybe a lockup.  If you have them in, take them out and try again.  Check the backside of all the bearing shells.  They should all have the same thousandths markings.  Those notches in the block and main caps were put there by the factory.  There're used to keep the bearing shell from rotating and caps, when installed will have that notch on the same side of the block as the one in the block.

Mine doesn’t use the rope seals it uses the old rubber 2 piece seal.

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50 minutes ago, Dave72dt said:

On your initial disassembly, do you recall any unusual wear patterns on the old bearings?

I didn’t, however this isn’t the same crank that came out of this engine, that one had a crack in it. The guy at the machine shop said he wants me to bring the block and crank back to him so he can check it all out.

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2 hours ago, TylerB46 said:

I didn’t, however this isn’t the same crank that came out of this engine, that one had a crack in it. The guy at the machine shop said he wants me to bring the block and crank back to him so he can check it all out.

 

I think you doing the best thing here, they did the work, let them stand behind it.....am sure they will come through for you.

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