Crankshaft end play? - 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 11-06-2008, 02:49 AM   #1
Junior Member
Thread Starter
iTrader: (5)
 
Join Date: Aug 2008
Location: Northbrook IL
Posts: 105
Total Cats: 0
Default Crankshaft end play?

What are the specs for the crankshaft end play on a 1.8L?
Max?
Min?
And what are good replacement bearings for a turbo with about 300+whp?
dima88 is offline   Reply With Quote
Old 11-06-2008, 03:31 AM   #2
Murderator
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 36,171
Total Cats: 2,574
Default

a turbo with about 300whp? wtf does that mean? that is so broad I dont even know where to start....perhaps you should list what kind of turbo it is and the specs and what not
18psi is offline   Reply With Quote
Old 11-06-2008, 04:36 AM   #3
Junior Member
Thread Starter
iTrader: (5)
 
Join Date: Aug 2008
Location: Northbrook IL
Posts: 105
Total Cats: 0
Default

ha ha that is not what i meant.

I need to know the specs for the crankshaft end play in a 1.8L engine, BP.

And I need to know what (performance)-> brand of rod and main bearings would work good in an engine that will make more the 300 whp.

Thanks
dima88 is offline   Reply With Quote
Old 11-06-2008, 09:10 AM   #4
AFM Crusader
iTrader: (18)
 
olderguy's Avatar
 
Join Date: Oct 2004
Location: Wayne, NJ
Posts: 4,438
Total Cats: 84
Default

On a 1.6 the specs are 0.0031" - 0.0111" Maximum of .012" I would suppose that the 1.8 is very similiar.
olderguy is offline   Reply With Quote
Old 11-06-2008, 03:46 PM   #5
Junior Member
Thread Starter
iTrader: (5)
 
Join Date: Aug 2008
Location: Northbrook IL
Posts: 105
Total Cats: 0
Default

I have about .020, I can i get away with only replacing the thrust bearing? or do i need to replace all the bearings?
dima88 is offline   Reply With Quote
Old 11-06-2008, 03:50 PM   #6
AFM Crusader
iTrader: (18)
 
olderguy's Avatar
 
Join Date: Oct 2004
Location: Wayne, NJ
Posts: 4,438
Total Cats: 84
Default

I would open it up and look at them. Book says to grind the crank and replace the thrust bearing with an oversize one. Personally, if there is no gauling(sp) on the crank, I would get an oversize thrust bearing and grind it down to fit.
olderguy is offline   Reply With Quote
Old 11-06-2008, 04:26 PM   #7
Junior Member
Thread Starter
iTrader: (5)
 
Join Date: Aug 2008
Location: Northbrook IL
Posts: 105
Total Cats: 0
Default

The engine is out of the car and opened, that is how i checked the end play, i think that the crankshaft is good so can i just put in a new thrust bearing or all new bearings, why do i have to put in an over sized one? the engine has about 25,000 miles after rebuild.
dima88 is offline   Reply With Quote
Old 11-06-2008, 04:34 PM   #8
Elite Member
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 8,796
Total Cats: 247
Default

Quote:
Originally Posted by dima88 View Post
The engine is out of the car and opened, that is how i checked the end play, i think that the crankshaft is good so can i just put in a new thrust bearing or all new bearings, why do i have to put in an over sized one? the engine has about 25,000 miles after rebuild.
You can't just throw bearings at an engine. Everything in it has to be perfect and to strict tolerances. There are even special methods of measuring pieces, and reassembling them, etc. If you're not extremely knowledgeable on building engines, I wouldn't try as odds are you'll **** it up. You're gonna have to get a machine shop to do a lot anyways. Just let them do it all. That way they assemble it and if they're a good shop, it should be right.

Also, there's a $20 Haynes manaul available for your year car that has all the engine specs in it.
patsmx5 is online now   Reply With Quote
Old 11-06-2008, 05:47 PM   #9
Junior Member
Thread Starter
iTrader: (5)
 
Join Date: Aug 2008
Location: Northbrook IL
Posts: 105
Total Cats: 0
Default

Dam i knew it wasent going to be easy. Do you think that i can get away with leaving the .020 end play? most likely not
dima88 is offline   Reply With Quote
Old 11-06-2008, 07:44 PM   #10
Elite Member
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 8,796
Total Cats: 247
Default

Is everything else about this engine perfect? If it needs a rebuild, you could just swap in a good used engine instead for cheap. The 1.8 BP came in a lot of other cars besides a miata.

I wouldn't leave .020 end play. That's not right.
patsmx5 is online now   Reply With Quote
Old 11-06-2008, 08:50 PM   #11
Junior Member
Thread Starter
iTrader: (5)
 
Join Date: Aug 2008
Location: Northbrook IL
Posts: 105
Total Cats: 0
Default

The engine has je oversized pistons, pauter rods, arp main caps. so i cant get a new one. and it has 25000 miles on it....is it too soon for it to have .020 end play?
I didnt buid it so i dont know if it was built right. so i have to take to an engine shop and have them fix the end play? i cant do it myself?
dima88 is offline   Reply With Quote
Old 11-06-2008, 09:23 PM   #12
AFM Crusader
iTrader: (18)
 
olderguy's Avatar
 
Join Date: Oct 2004
Location: Wayne, NJ
Posts: 4,438
Total Cats: 84
Default

Quote:
Originally Posted by dima88 View Post
The engine is out of the car and opened, that is how i checked the end play, i think that the crankshaft is good so can i just put in a new thrust bearing or all new bearings, why do i have to put in an over sized one? the engine has about 25,000 miles after rebuild.
The thrust bearing is only half a bearing, trapped between the journal and the side of the crank. You would go oversize to fill the space that has either worn off the crank or that you grind off to flatten it. The side against the journal doesn't wear.

Check the actual allowance for a 1.8 before you do anything except pull out the old one. The spec MAY be more open.
olderguy 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
OTS Bilstein to motorsports ASN conversion stoves Suspension, Brakes, Drivetrain 5 04-21-2016 04:00 PM
Expected intake temps on the track? tazswing Race Prep 20 10-03-2015 12:04 PM
Time to start learning and play with tuning The Gleas MEGAsquirt 3 10-01-2015 10:30 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 07:03 PM.