Show full size 924Board.org
Discussion Forum of 924.org
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 
 Technical FAQ924 FAQ (Technical)   Technical924 Technical Section   Jump to 924.org924.org   Jump to PCA 924 Registry924 Registry

K26 Billet Compressor Wheel
Goto page Previous  1, 2
 
Post new topic   Reply to topic    924Board.org Forum Index -> Performance Upgrades
View previous topic :: View next topic  
Author Message
Moparboy72  



Joined: 29 Jul 2014
Posts: 26
Location: Naperville, IL

PostPosted: Wed Aug 29, 2018 3:02 am    Post subject: Reply with quote

Fasteddie313 wrote:
http://www.924board.org/viewtopic.php?t=40119
What are the tag numbers on the turbo you pulled off your car?
2664 or 2660?

Unfortunately, there is no tag on this turbo; I did find a portion of what may be a rebuilders/reman tag on one of the compressor housing bolts but there is not enough of the tag to make anything out of it.

Fasteddie313 wrote:
What do you think is wrong with your turbine wheel? Is their a crack in the blade or just the carbon on it or what?
There is a crank in the blade in the photo, A number of the blades on wheel look worn, a bit deformed.

Fasteddie313 wrote:
I'm not 100% sure about your compressor wheel by the photo.. Does it have damage on the inducer like it ate something? Was it scuffing the housing on the blade edges? Look shiny..
Comp wheel has passed some debris, no scuffing on the housing but it looks to have been sand blasted as some point and there is a fine grit on most surfaces. The bypass valve was seized in its housing due to this grit/sand.

Fasteddie313 wrote:
I think your housing crack is a bit on the larger side but if it isn't touching the wheel, or threatening to, then it's probably fine..
I have a spare but it has a crack, just like the one I'm running has a crack..
Understood; that seems to be the consensus around here. I'll move forward with this housing as is for now.

Fasteddie313 wrote:
If you have a 2660 turbo I don't think I saw comp wheels for it, but I have seen billet comp wheels on ebay for the 2664..

I ordered up the one from ebay which per the measurements would be near correct. I plan to follow up once it is received.

Fasteddie313 wrote:
How is the turbine piston, comp piston, ring grooves, cylinders on both sides? Are you buying a rebuild kit?
How is the turbine shaft where the bearings ride? No groove? Bearing housing fine where the bearings go?

The rings in the turbine piston look a bit worse for wear (loose); alot of coked oil deposits on the turbine heat shield (may be normal for age). I am planning on buying a rebuild kit, thought the bearing housing and bearings I have seem fine, I am in need of the o-rings for the comp cover and base plate.

Where do you source genuine Borg/kkk parts from? I was thinking of also replacing the compressor wheel nut.

Thanks again,

Andrew
Back to top
View user's profile Send private message
Mike9311  



Joined: 14 Dec 2004
Posts: 678
Location: Chicago-ish

PostPosted: Wed Aug 29, 2018 10:39 pm    Post subject: Reply with quote

My turbine housing in the S2 is also cracked but working fine
_________________
1980 931 ...off with the cobwebs
1982 931 Entwicklungsfahrzeug
1979 924 NA M471/M481 / ohne M650 Herausnehmbares Dach
0.5 1982 931 smashed parts car
1982 931 parts car?
1980 924 NA (R&D lightweight)
1982 931 WB wana-be GTR race car
Back to top
View user's profile Send private message
Fasteddie313  



Joined: 29 Sep 2013
Posts: 1561
Location: MI

PostPosted: Thu Aug 30, 2018 10:09 am    Post subject: Reply with quote

the large cast part number on your compressor housing can identify the turbo, their should also be a part number on the back of the compressor wheel..
_________________
80 Turbo - Slightly Modified
Back to top
View user's profile Send private message Yahoo Messenger
Carrera RSR  



Joined: 08 Jan 2010
Posts: 1602
Location: Somerset, UK

PostPosted: Thu Aug 30, 2018 11:37 pm    Post subject: Reply with quote

Fasteddie313 wrote:
the large cast part number on your compressor housing can identify the turbo,


Turbine housing size, not turbo pe se

Fasteddie313 wrote:
their should also be a part number on the back of the compressor wheel..


Not always. But the casting number on the compressor housing will lead you to which wheel in inside, unless the housing has been machined for an alternative wheel.

I supplied what I believed to be a S1 K26 2470 6.10 and a S2 K26 2664 4.10, both RoW to a turbo rebuilder. Both turned out to be K26 2660 6.10. Both did not have compressor wheel part numbers. I have educated myself a little more since then.

The other issue is RoW and US specs of S1 and S2 turbos have changed and posts on here can be a little confusing for the less knowledgable.
_________________
1980 931 - forged pistons, Piper cam, CGT turbo, 951 ducted FMIC, custom intake, Mittelmotor dizzy & cam pulley, H&S exhaust, GAZ Gold, Fuch'ed, Quaife LSD
Now www.924board.org/viewtopic.php?t=34690
Then www.924board.org/viewtopic.php?t=31252
Back to top
View user's profile Send private message
Moparboy72  



Joined: 29 Jul 2014
Posts: 26
Location: Naperville, IL

PostPosted: Sat Sep 01, 2018 12:39 am    Post subject: Reply with quote

The compressor wheel has the following number hand written in marker on the back face, K26.123.2017D .

The part number cast into the compressor housing are 5326 101 5190F

The number cast into the inside of the turbine housing inlet is "4".

I have received the replacement turbine and compressor wheels. The only other point to make in addition to Ciprian/morghen's note of needing more turbine shaft length due to turbine wheel height increase. The replacement turbine wheel I sourced (eBay/Taiwan) is now M7x1.00 RH thread instead of M6 as the original shaft.

I will be sending out the rotating parts for balancing once I source a M7 CCW nut.
Thanks again for all the input!

-Andrew
Back to top
View user's profile Send private message
Carrera RSR  



Joined: 08 Jan 2010
Posts: 1602
Location: Somerset, UK

PostPosted: Sat Sep 01, 2018 10:59 am    Post subject: Reply with quote

With those part numbers you have a 2660 compressor wheel and housing. You have a #4 turbine housing.
_________________
1980 931 - forged pistons, Piper cam, CGT turbo, 951 ducted FMIC, custom intake, Mittelmotor dizzy & cam pulley, H&S exhaust, GAZ Gold, Fuch'ed, Quaife LSD
Now www.924board.org/viewtopic.php?t=34690
Then www.924board.org/viewtopic.php?t=31252
Back to top
View user's profile Send private message
Moparboy72  



Joined: 29 Jul 2014
Posts: 26
Location: Naperville, IL

PostPosted: Thu Sep 06, 2018 4:59 am    Post subject: Reply with quote

I spend some time further cleaning up the turbine housing and found that it had previously been repaired where the largest crack is. Further research also pointed me to the technical bulletin 81-04 which shows the three types of turbine housings which gaskets are used and part numbers.

According the bulletin, the turbine housing I have is a type II, which uses a sealing ring for the turbine inlet and a flat metal gasket for the outlet. This tells me the turbo was a reman/exchange unit at some point as this type of housing was only factory fitted to 1980 MY 931s. 1981MY+ would have a type III with a sealing ring for the turbine inlet and outlet.

Lastly I did some weighing of the old/new turbines and the old/new compressor wheels. The caveat here is the kitchen scale is not the most accurate but I was just curious to gauge any differences.

Compressor (old/new) 60g/50g
Turbine (old/new) 280g/305g

I will try to post some photos later to show the differences.

Thanks all,

Andrew
Back to top
View user's profile Send private message
Moparboy72  



Joined: 29 Jul 2014
Posts: 26
Location: Naperville, IL

PostPosted: Fri Sep 07, 2018 1:51 am    Post subject: Reply with quote

Turbine compare, new turbine is longer (not trimmed):



Turbine compare, new wheel is thicker in the fins/blades especially at the base:


New wheel with old turbine, showing a bit short on threads:



New wheel with new turbine, showing a bit long but may be short on threads, I will have to see how the M7 nut measures up:



Turbine housing with previous weld/repair:



A pin hole through one of the down pipe stud holes below:

Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    924Board.org Forum Index -> Performance Upgrades All times are GMT + 11 Hours
Goto page Previous  1, 2
Page 2 of 2

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group