Buying Used - need advice - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


DIY Turbo Discussion greddy on a 1.8? homebrew kit?

Reply
 
 
 
LinkBack Thread Tools
Old 01-23-2007, 04:58 PM   #1
Newb
Thread Starter
 
Join Date: Jan 2007
Posts: 14
Total Cats: 0
Default Buying Used - need advice

Hi all,

I'm currently slowly piecing together a DIY system for my '96 and using the FAQ as a guide. Currently I'm looking for a T25 off of an Nissan SR20 engine, but I've never looked at Turbos before, let alone used turbos. What should I look out for when buying used? I've read terms like "shaft play" but I don't really understand what that means.

Any help/links would be appreciated.

Thanks.
miatanewb is offline   Reply With Quote
Old 01-23-2007, 05:11 PM   #2
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,892
Total Cats: 1,792
Default

shaft play means the shaft of the turbine can move around freely. Ususally some in/out (front to back) is fine. Any side/side and it means there is space for the turbine to move around....this means the bearings are worn down and it's not good on the shaft.

check the blades, they shouldn't be worn at all.

See if you can't spot any oil leakage. (check the turbine area, you'll see carbon, but oil shouldn't be there)

All in all, if the condition of the blades are good you can rebuild them cheap.



also remember I wrote that FAQ a little 89-93 biased, so there might be a few variances you need to watch out for (oil feed, AFM vs. MAF)
Braineack is offline   Reply With Quote
Old 01-23-2007, 05:38 PM   #3
Elite Member
iTrader: (3)
 
Join Date: May 2006
Location: Houston, TX
Posts: 2,900
Total Cats: 0
Default

fyi... some lateral play is normal in a non BB turbo.
Arkmage is offline   Reply With Quote
Old 01-23-2007, 05:59 PM   #4
Elite Member
iTrader: (13)
 
cjernigan's Avatar
 
Join Date: Oct 2006
Location: Atlanta, GA
Posts: 8,147
Total Cats: 6
Default

I highly recommend taking the housings off when buying it as well to inspect the wheels. A wheel could have made contact inside the housing and you would never be able to see it from just the outside. You'll need a beefy pair of 90* snapring pliers or big like 8" 90* needle nose (i use needlenose, they're strong). You'll use the pliers to remove the compressor housing which is easy. You'll also need a wrench to remove the turbine housing, the SR20 T25's are a 13mm bolt on the turbine side.
After looking a bunch of used turbos and almost getting screwed 2/3 times i refuse to buy without disassembly photos or taking it apart myself before cash is handed over.
cjernigan is offline   Reply With Quote
Old 01-23-2007, 06:06 PM   #5
Miotta FTW!
iTrader: (24)
 
Splitime's Avatar
 
Join Date: Jun 2006
Location: Chicagoland, IL
Posts: 4,295
Total Cats: 26
Default

Quote:
Originally Posted by Arkmage View Post
fyi... some lateral play is normal in a non BB turbo.
Apparently its acceptable in a BB turbo also. Not a ton, but it tightens up with oil in it just like a journal bearing turbo.
Splitime is offline   Reply With Quote
Old 01-23-2007, 06:28 PM   #6
Elite Member
iTrader: (9)
 
Join Date: Aug 2006
Location: Concord, North Carolina
Posts: 4,173
Total Cats: 5
Default

^ thats true
miatamania is offline   Reply With Quote
Old 01-23-2007, 07:02 PM   #7
Newb
Thread Starter
 
Join Date: Jan 2007
Posts: 14
Total Cats: 0
Default

Great, thanks for your help!
miatanewb is offline   Reply With Quote
Old 01-23-2007, 08:25 PM   #8
Elite Member
iTrader: (8)
 
Join Date: Sep 2006
Location: Severn, MD
Posts: 1,927
Total Cats: 5
Default

Cracks around the wastegate flapper or anywhere on the turbine housing for that matter. Chipped fins on the compressor wheel indicating the turbo ingested something.

I doubt you'll find many sellers that will let you take a turbo apart.

Frank
fmowry is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Need help - Stock Balancer and Fastforward overlay pulleys Frank_and_Beans Supercharger Discussion 13 09-12-2016 09:17 PM
WTB Bellhousing Bolts patsmx5 WTB 1 10-01-2015 10:43 AM
Any pnp megasquirt for 2001 Big_gumby WTB 0 09-30-2015 04:34 PM


Thread Tools

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 03:28 AM.