Crankshaft hard to turn by hand after rebuild - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Engine Performance This section is for discussion on all engine building related questions.
Sponsored by:
Sponsored by:

Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 06-21-2013, 10:04 AM   #1
Junior Member
Thread Starter
iTrader: (1)
 
Join Date: Jan 2008
Posts: 161
Total Cats: 0
Default Crankshaft hard to turn by hand after rebuild

Allright, here we go again.

I did the big mistake of cleaning a while back my garage, and throwing in a bin all the crankshaft caps in a bucket (from three different engine blocks).

Now, after about a year, I decided to hands on and build one of the blocks. Checked for everything, gasket seal kit, piston rings, rod bearings, metal head gasket, etc, but everything is on a halt now.

Yesterday I finished installing the crankshaft bearings, crankshaft, thrust washer, etc, and when I torqued everything down in 3 stage sequence to 10 foot of torque, the crank would not rotate. There is nothing else on the block, only the crank, and I recall it should rotate freely with minimal resistance. The bearings are King STD, lubed all moving parts with fresh engine oil, all caps are facing toward the front of the engine, and they are in their corresponding number locations.

Noticing things were not working right, grabbed another crankshaft, and the same deal, very hard to turn by hand, and no crankshaft play at all.

I have one thing, I am not sure if the caps used are from that engine block.

Does the crankshaft caps have to be from that specific engine block?

And if not, Is there an affordable easy way to get it to work?
I heard of inline boring, but not sure if its a good idea or not.
psiturbo is offline   Reply With Quote
Old 06-21-2013, 10:20 AM   #2
Elite Member
 
Join Date: Apr 2010
Location: Newcastle, Australia
Posts: 2,639
Total Cats: 25
Default

Quote:
Originally Posted by psiturbo View Post
Allright, here we go again.

I did the big mistake of cleaning a while back my garage, and throwing in a bin all the crankshaft caps in a bucket (from three different engine blocks).

Now, after about a year, I decided to hands on and build one of the blocks. Checked for everything, gasket seal kit, piston rings, rod bearings, metal head gasket, etc, but everything is on a halt now.

Yesterday I finished installing the crankshaft bearings, crankshaft, thrust washer, etc, and when I torqued everything down in 3 stage sequence to 10 foot of torque, the crank would not rotate. There is nothing else on the block, only the crank, and I recall it should rotate freely with minimal resistance. The bearings are King STD, lubed all moving parts with fresh engine oil, all caps are facing toward the front of the engine, and they are in their corresponding number locations.

Noticing things were not working right, grabbed another crankshaft, and the same deal, very hard to turn by hand, and no crankshaft play at all.

I have one thing, I am not sure if the caps used are from that engine block.

Does the crankshaft caps have to be from that specific engine block?

Yes.

And if not, Is there an affordable easy way to get it to work?
I heard of inline boring, but not sure if its a good idea or not.
Dann
nitrodann is offline   Reply With Quote
Old 06-21-2013, 10:25 AM   #3
Murderator
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 36,186
Total Cats: 2,582
Default

lolzfail
18psi is offline   Reply With Quote
Old 06-21-2013, 10:27 AM   #4
Elite Member
iTrader: (2)
 
miata2fast's Avatar
 
Join Date: Aug 2009
Location: Dover, FL
Posts: 2,895
Total Cats: 109
Default

If you ever have to use other caps or get them mixed up, you will need to have the block align bored along the crankshaft axis. It is possible some caps may need resizing.

It was an unfortunate mistake, but a problem that can be fixed. I do not recall what it cost me to have it done. When you switch over to main studs, it should be done anyways.

Last edited by miata2fast; 06-22-2013 at 02:44 PM.
miata2fast is offline   Reply With Quote
Old 06-21-2013, 12:26 PM   #5
Junior Member
 
Join Date: May 2012
Posts: 68
Total Cats: -3
Default

You could use Plastigage to find a set that fits. Pain in the *** with that many caps...
compaddict is offline   Reply With Quote
Old 06-21-2013, 12:35 PM   #6
Moderator
iTrader: (11)
 
sixshooter's Avatar
 
Join Date: Nov 2008
Location: Tampa, Florida
Posts: 15,669
Total Cats: 1,560
Default

Every one is different.

You won a trip to the machine shop.
sixshooter is offline   Reply With Quote
Old 06-21-2013, 12:36 PM   #7
Elite Member
iTrader: (10)
 
soviet's Avatar
 
Join Date: Jan 2010
Location: VA
Posts: 3,518
Total Cats: 257
Default

Yeah you need to line bore/hone, just like you would with billet main caps
soviet is offline   Reply With Quote
Old 06-21-2013, 01:04 PM   #8
Junior Member
Thread Starter
iTrader: (1)
 
Join Date: Jan 2008
Posts: 161
Total Cats: 0
Default

I completely dropped the ball on this one. Yesterday I spent around 3 hours reading the manual back to back to see if I was missing anything. Looked everywhere on the block for anything restricting it from moving, surfing the internet until someone posted about the correct caps in another forum. Complete tunnel vision, out of the park, I know...

Oh well, got some extra work, i will fix it though.
psiturbo is offline   Reply With Quote
Old 06-21-2013, 01:18 PM   #9
Supporting Vendor
iTrader: (31)
 
Savington's Avatar
 
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 14,363
Total Cats: 1,324
Default

Did you take any sort of measurement to check the oil clearance?
Savington is offline   Reply With Quote
Old 06-21-2013, 02:14 PM   #10
Junior Member
Thread Starter
iTrader: (1)
 
Join Date: Jan 2008
Posts: 161
Total Cats: 0
Default

No, I did not.

I have done this before without taking any measurements. I do torque like its suppose to, check for crank play and amount of torque needed to rotate. According to specs it must be no more than 5 pounds of torque to spin freely. Doing the rebuild from a bad machine work done to it a while back.
psiturbo is offline   Reply With Quote
Old 06-21-2013, 02:23 PM   #11
Cpt. Slow
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 12,107
Total Cats: 518
Default

You got lucky before. Pick up some plastigage and measure your oil clearances. You'll need to do it anyways if you line bore, as you'll need to use oversized bearings.
curly is offline   Reply With Quote
Old 06-21-2013, 02:52 PM   #12
Moderator
iTrader: (11)
 
sixshooter's Avatar
 
Join Date: Nov 2008
Location: Tampa, Florida
Posts: 15,669
Total Cats: 1,560
Default

You do know that the rod caps are similarly unique one to another with each rod, right?
sixshooter is offline   Reply With Quote
Old 06-21-2013, 10:47 PM   #13
Junior Member
Thread Starter
iTrader: (1)
 
Join Date: Jan 2008
Posts: 161
Total Cats: 0
Default

(edited for obvious reasons)

Last edited by psiturbo; 06-22-2013 at 09:41 AM.
psiturbo is offline   Reply With Quote
Old 06-22-2013, 01:13 AM   #14
Supporting Vendor
iTrader: (31)
 
Savington's Avatar
 
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 14,363
Total Cats: 1,324
Default

Quote:
Originally Posted by psiturbo View Post
Yeah, that is why they sell the forged rods with the main caps...
He was asking whether you knew that you couldn't mix them up, or even install them backwards, without damaging the engine.

Measure your oil clearances, dude.
Savington is offline   Reply With Quote
Old 06-22-2013, 09:40 AM   #15
Junior Member
Thread Starter
iTrader: (1)
 
Join Date: Jan 2008
Posts: 161
Total Cats: 0
Default

Quote:
Originally Posted by sixshooter View Post
You do know that the rod caps are similarly unique one to another with each rod, right?
My bad, yeah I do know that. I got forged rods M-Tuned...

On stock rods they have a marking from factory, and those I got them all matched like its suppose to.
psiturbo is offline   Reply With Quote
Old 06-22-2013, 07:12 PM   #16
Junior Member
Thread Starter
iTrader: (1)
 
Join Date: Jan 2008
Posts: 161
Total Cats: 0
Default




It was the set on the right.




After a few hours, patience, trial and error, finally figured out which one was the set for the block. Now it turns like butter and the caps simply drop in without minimal effort.

Lesson learned, thank you everyone!
Attached Thumbnails
Crankshaft hard to turn by hand after rebuild-crank_caps.jpg   Crankshaft hard to turn by hand after rebuild-crank_block.jpg  
psiturbo is offline   Reply With Quote
Old 06-22-2013, 07:17 PM   #17
Supporting Vendor
iTrader: (31)
 
Savington's Avatar
 
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 14,363
Total Cats: 1,324
Default

Did you measure the clearances?
Savington is offline   Reply With Quote
Old 06-22-2013, 07:31 PM   #18
Junior Member
 
Join Date: May 2012
Posts: 68
Total Cats: -3
Default

+1
compaddict is offline   Reply With Quote
Old 06-22-2013, 07:38 PM   #19
Cpt. Slow
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 12,107
Total Cats: 518
Default

You're missing an oil jet.
curly is offline   Reply With Quote
Old 06-22-2013, 08:26 PM   #20
Supporting Vendor
iTrader: (31)
 
Savington's Avatar
 
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 14,363
Total Cats: 1,324
Default

Quote:
Originally Posted by curly View Post
You're missing an oil jet.
Two, actually.
Savington is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Buzzing from driver side of engine bay? (MS3 install) nick470 MEGAsquirt 7 06-16-2017 02:53 PM
1991 special edition with hard top full part out JC, NJ russian Miata parts for sale/trade 6 10-08-2015 04:01 PM
Expected intake temps on the track? tazswing Race Prep 20 10-03-2015 12:04 PM
Walbro 255lph Fuel Pump $50 lsc224 Miata parts for sale/trade 2 10-01-2015 10:17 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 12:59 PM.