Built engine wont turn when gearbox gets tightened up - 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 05-18-2014, 07:30 PM   #1
Senior Member
Thread Starter
iTrader: (1)
 
Join Date: Jun 2006
Location: Sweden
Posts: 1,391
Total Cats: 58
Default Built engine wont turn when gearbox gets tightened up

I need some suggestion since this is the second time this happens when the built engine goes back in.

After a lot of cursing the mating was successful (one of the guides usually misbehaves), and then all the fighting with the AWR mounts (softest bushings this time).
So when tightening the gearbox and starter up I just tried to turn the engine by hand to verify and it's stuck.
Loosening the gearbox+starter just a little makes it turn just as it was in the stand.
The clutch pack is a SuperMiata single race clutch and I never had this problems before we build the bottom end. 5speed with Mazda semi-straight gears and a 02 block.

I don't remember if I left it loose last time or tightened it after some minutes of running (the current plan for tomorrow (some hours of wrenching left before startup).

Is something just misaligned and it will shake in place or is the gearbox input shaft bottoming in the crank (but wouldn't that require the thrust bearing and oil pump to be terribly wrong)?
The stock engine I use for inspections just falls in place on its own now so this is something specific to this engine (same clutch was use before it was built and I don't think I had this problem then).
NiklasFalk is offline   Reply With Quote
Old 05-19-2014, 12:16 AM   #2
Supporting Vendor
iTrader: (31)
 
Savington's Avatar
 
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 14,362
Total Cats: 1,323
Default

Check the pilot bearing alignment in the flywheel. If it's out, the input shaft presses up against it, doesn't press onto it, and nothing will turn.
Savington is offline   Reply With Quote
Old 05-19-2014, 11:27 AM   #3
Senior Member
Thread Starter
iTrader: (1)
 
Join Date: Jun 2006
Location: Sweden
Posts: 1,391
Total Cats: 58
Default

Thanks for pointing out what I've missed.
The pilot bearing was installed flush but could be tapped in another.05" or so.
Now it's back in there and I only have to fight with one dowel pin and the pesky engine mounts.
NiklasFalk is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 57 07-19-2017 05:11 PM
Changing from 460cc to flow force 610cc in diypnp 90 Turbo MEGAsquirt 19 10-19-2015 04:23 PM
Walbro 255lph Fuel Pump $50 lsc224 Miata parts for sale/trade 2 10-01-2015 10:17 AM
Leaky Wilwoods mx592 Suspension, Brakes, Drivetrain 1 10-01-2015 01:45 AM
Bad head gasket or ? shooterschmidty Engine Performance 8 09-30-2015 11:28 PM


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 07:28 AM.