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Re: Need help verifying fit of crank, camshaft, bearings
Posted by: cwdaveroch ()
Date: August 04, 2017 07:26PM

Thanks. Tomorrow is crankshaft day!

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Re: Need help verifying fit of crank, camshaft, bearings
Posted by: cwdaveroch ()
Date: August 05, 2017 03:33PM

OK, I`m hoping "run that block" means to go ahead and use it.

Today I did the same with the crankshaft. Clearances were 0.003 on journals 1 and 2, and 0.0015 on 3 and 4. Manual says for new bearings on 1 and 2 should be between 0.0012 and 0.0027, but 0.004 is acceptable for old. For 3 and 4, the clearance for new is 0.007 to 0.022, so I am in the range there.

I'm thinking that should be OK, so please let me know if I need to replace bearings with a different set.

Tomorrow I will do the clearance test for rods, and if that goes well I can start cleaning and assembling Monday!

Thanks again for the help.

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Re: Need help verifying fit of crank, camshaft, bearings
Posted by: cwdaveroch ()
Date: August 07, 2017 07:21PM

The block halves are together! I can easily turn the crankshaft by hand. There is one place in the rotation of the cam that has a slight tug. When it gets to that spot it hesitates a bit. If I am turning it with any force I don't notice, but turnimg it slowly I feel a catch, always in the same place on the cam gear. I have looked at the gear and don't see any obvious imperfections. It's not my original, but can't remember if I purchased from Lon or Clarks. Should I be concerned?

Tomorrow starting on the rear housing. I'll search posts to read before I start, but if anyone has advic3, feel free to share.

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Re: Need help verifying fit of crank, camshaft, bearings
Posted by: jjohnsonjo ()
Date: August 08, 2017 05:07AM

Cam might not be straight, you can put it on "V" blocks and check with a dial indicator, or have a machine shop check it for you.

J.O.

65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo

Bethlehem,Pa

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Re: Need help verifying fit of crank, camshaft, bearings
Posted by: Wagon Master ()
Date: August 08, 2017 05:29AM

If it was tight enough to cause me concern, I would coat the cam gear teeth with a Sharpie or layout fluid and roll it through several cycles. You should be able to see a clearance issue with the gear teeth as a place where to coating has rubbed off.

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Re: Need help verifying fit of crank, camshaft, bearings
Posted by: Noel Felty ()
Date: August 08, 2017 09:30AM

Check and make sure your cam gear is clear of any debris as well. Don't assemble until you find the catch. A small catch could mean big wear under a load.

Noel Felty
Brevard, NC
1966 Corsa 140 Before

1966 Corsa After

1972 Ford f100

Corsa SC
NC Mountain Corvairs

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Re: Need help verifying fit of crank, camshaft, bearings
Posted by: cwdaveroch ()
Date: August 08, 2017 07:09PM

Hated to do it but I spent all day trying to figure out the small catch in the camshaft/crankshaft gears. My first assumption was wrong. The problem is in the crankshaft. I thought it was occuring only every other crank rotation, but turning very slowly I could feel it once per rotation. Just to make sure I marked where the catch was and mis-aligned the camshaft by 90 degrees and the catch was still in the same place on the crank gear. I double cleaned everything again and tried again, and the catch is still there in the same place. I can't see anything wrong with the gear, and don't have good enough tools to test for out of round, so I will take it to the shop tomorrow and let them spec it out and see if they can find a reason.

Good news is I'll have even more time to clean the shrouds. I've been putting that off for several years.

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Re: Need help verifying fit of crank, camshaft, bearings
Posted by: jimc ()
Date: August 08, 2017 07:54PM

Though this may not cause the "catch or binding" you experienced, did you verify that the one main bearing shell, not flange or thrust bearing, and should have a different part number, is slightly thicker at top than bottom is correctly installed in the case, this is covered in the manual.

That bearing shell with a different part number may also have a color coating on edge of bearing to identify it is different. One end of this bearing half is actually a different thickness (.0015 off center) and has affect of lowering the crank center line at flywheel, if I remember correctly.

Jimc
1965 Corsa

HACOA member
AACA 2015 Award
CORSA 2017 Concours Senior Award

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Re: Need help verifying fit of crank, camshaft, bearings
Posted by: cwdaveroch ()
Date: August 08, 2017 08:04PM

One bearing has edges that overlap the sides, Is that what you mean? Or is one of the other three slightly different? If so, I didn't check that when installing. I will check the manual again. As I said, the bearings just came loose taped up in an old box with no part numbers.

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Re: Need help verifying fit of crank, camshaft, bearings
Posted by: jimc ()
Date: August 08, 2017 08:16PM

No, I think you are referring to the main bearing with flanges that functions as a thrust bearing.

I am speaking of a typical looking "shell" bearing without any flanges and has a different part number stamped on back and possibly a color coded edge. It would look like a typical main bearing for #2, #3 and #4 crankshaft bearing positions, except for the slightly thicker end.

Jimc
1965 Corsa

HACOA member
AACA 2015 Award
CORSA 2017 Concours Senior Award

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Re: Need help verifying fit of crank, camshaft, bearings
Posted by: cwdaveroch ()
Date: August 08, 2017 08:18PM

I will definitely check that.

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Re: Need help verifying fit of crank, camshaft, bearings
Posted by: cwdaveroch ()
Date: August 09, 2017 05:47PM

Checked the bearings and they were correct. I placed the bearings in the block just before I moved three years ago, and I'm sure I used the manual and placed them accordingly.

Cylinders #2 and #3: MB 1520-4 0.01

Cylinder #4: MB 1510-2 0.01

Took the block, camshaft, and crankshaft to the shop today. Spent some time with the mechanic showing him where I marked the spot that catches and he rotated it himself and felt it, too, so he knows where the problem is. He identified a very small score on the inside edge of the two teeth that are giving trouble, and he said that little score may be pushing out the face of the tooth enough to cause the trouble. He'll work with a file and dremel to smooth it out and hopefully that will be all I need. Just for fun I looked up the price of a new gear at Clarks. About $100, so if I need to I can do that and have the shop press the new one on.

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