Shortnose Crank Issue
Moderators: timk, Stu, -alex, miata, StanTheMan, greenMachine, ManiacLachy, Daffy, zombie, Andrew, The American, Lokiel
- SuperMazdaKart
- Racing Driver
- Posts: 1980
- Joined: Tue Oct 26, 2004 9:10 pm
- Vehicle: ND - 2 GT
- Location: Adelaide
Shortnose Crank Issue
1.8 if your prepared to go with it's ECU & other needed stuff as well.
or a used good 1.6 engine.
or a very low K 98+ model NB6 1.6L engine slightly adapted to run with the 89-93 NA6 ECU & ancillaries etc
or a used good 1.6 engine.
or a very low K 98+ model NB6 1.6L engine slightly adapted to run with the 89-93 NA6 ECU & ancillaries etc
- corners
- Racing Driver
- Posts: 1127
- Joined: Mon Aug 20, 2007 1:33 pm
- Vehicle: ND - Supercharged
- Location: Brisbane, QLD
Shortnose Crank Issue
Does anyone know if the B6 SOHC has the same block as the B6 DOHC?
Cheers
Cheers
Steampunk wrote: Oh you've got Ohlins? You must like drugs too!!!
- sabretooth
- Speed Racer
- Posts: 2119
- Joined: Wed Apr 23, 2003 11:00 am
- Vehicle: NA8 - Turbo
Shortnose Crank Issue
I wouldn't waste your time with a 1.8 upgrade. The difference is not significant enough.
- corners
- Racing Driver
- Posts: 1127
- Joined: Mon Aug 20, 2007 1:33 pm
- Vehicle: ND - Supercharged
- Location: Brisbane, QLD
Shortnose Crank Issue
I am most likely going with a 1600
What do people suggest replacing whilst out of the car?
I was considering the following parts but not sure of genuine or after market.
Crank Bolt
Timing Belt
Water Pump
Drive Belts
Clutch
Rear Seal
Nothing else springs to mind..
What do people suggest replacing whilst out of the car?
I was considering the following parts but not sure of genuine or after market.
Crank Bolt
Timing Belt
Water Pump
Drive Belts
Clutch
Rear Seal
Nothing else springs to mind..
Steampunk wrote: Oh you've got Ohlins? You must like drugs too!!!
-
- Forum Guru
- Posts: 4897
- Joined: Mon Apr 24, 2006 7:27 pm
- Vehicle: NA8
- Location: Moruya, NSW
Shortnose Crank Issue
jcs86 wrote:I am most likely going with a 1600
What do people suggest replacing whilst out of the car?
I was considering the following parts but not sure of genuine or after market.
Crank Bolt
Timing Belt
Water Pump
Drive Belts
Clutch
Rear Seal
Nothing else springs to mind..

Crank Bolt + Woodruff key - Genuine
Timing Belt pulley and/or Crank Pulley boss, if keyways spread at all - Genuine
Timing Belt , idlers, tension spring, cam seals, front oil seal, water pump - aftermarket kit
Drive Belts - aftermarket
Clutch - Exedy Sports
Rear Seal - Genuine or good quality aftermarket
CAS O-ring at back of exhaust cam on NA6(?) - aftermarket
Check all the main coolant hoses - aftermarket
Replace all the other little coolant water hoses that lurk around the front, back and sides of the motor - aftermarket and cheapest by the meter.
Check clutch slave cylinder - aftermarket
Check gearbox front seal - genuine (?)
’95 NA8
- corners
- Racing Driver
- Posts: 1127
- Joined: Mon Aug 20, 2007 1:33 pm
- Vehicle: ND - Supercharged
- Location: Brisbane, QLD
Shortnose Crank Issue
Thanks
Is doing the crank stuff hard? What do you use to stop the engine from turning?
Is doing the crank stuff hard? What do you use to stop the engine from turning?
Steampunk wrote: Oh you've got Ohlins? You must like drugs too!!!
- corners
- Racing Driver
- Posts: 1127
- Joined: Mon Aug 20, 2007 1:33 pm
- Vehicle: ND - Supercharged
- Location: Brisbane, QLD
Shortnose Crank Issue
Does anyone know the part numbers for the B6 longnose bolt and woodruff key?
Steampunk wrote: Oh you've got Ohlins? You must like drugs too!!!
-
- Forum Guru
- Posts: 4897
- Joined: Mon Apr 24, 2006 7:27 pm
- Vehicle: NA8
- Location: Moruya, NSW
Shortnose Crank Issue
jcs86 wrote:Does anyone know the part numbers for the B6 longnose bolt and woodruff key?
Just go to Mazda with the old parts and the engine number. I just paid about $15 to them here in Vic for both the bolt and key. Not worth chasing aftermarket at that price.
If you're replacing the clutch then you can lock the flywheel by screwing in a couple of old bolts in the clutch mounting holes and running a bar across them.
’95 NA8
- corners
- Racing Driver
- Posts: 1127
- Joined: Mon Aug 20, 2007 1:33 pm
- Vehicle: ND - Supercharged
- Location: Brisbane, QLD
Shortnose Crank Issue
manga_blue wrote:jcs86 wrote:Does anyone know the part numbers for the B6 longnose bolt and woodruff key?
Just go to Mazda with the old parts and the engine number. I just paid about $15 to them here in Vic for both the bolt and key. Not worth chasing aftermarket at that price.
If you're replacing the clutch then you can lock the flywheel by screwing in a couple of old bolts in the clutch mounting holes and running a bar across them.
Cool
Thanks for your help and advice Manga!
Steampunk wrote: Oh you've got Ohlins? You must like drugs too!!!
- SuperMazdaKart
- Racing Driver
- Posts: 1980
- Joined: Tue Oct 26, 2004 9:10 pm
- Vehicle: ND - 2 GT
- Location: Adelaide
Shortnose Crank Issue
manga_blue wrote:jcs86 wrote:Does anyone know the part numbers for the B6 longnose bolt and woodruff key?
Just go to Mazda with the old parts and the engine number. I just paid about $15 to them here in Vic for both the bolt and key. Not worth chasing aftermarket at that price.
If you're replacing the clutch then you can lock the flywheel by screwing in a couple of old bolts in the clutch mounting holes and running a bar across them.
that cheap? mine was much more costly then that...
-
- Fast Driver
- Posts: 294
- Joined: Mon Sep 01, 2008 1:33 pm
- Vehicle: ND - 2 GT
- Location: Brisbane bayside
Shortnose Crank Issue
jcs86, PM zoom zoom ( Tim ) he has done lots of these and did mine for me , he will know the part numbers and will only be too happy to give his valuable advice. his work is faultless .
He is in Brisbane as well.
He is in Brisbane as well.
Bond, James Bond. growing old is not an option, growing up is
- corners
- Racing Driver
- Posts: 1127
- Joined: Mon Aug 20, 2007 1:33 pm
- Vehicle: ND - Supercharged
- Location: Brisbane, QLD
Shortnose Crank Issue
grump wrote:jcs86, PM zoom zoom ( Tim ) he has done lots of these and did mine for me , he will know the part numbers and will only be too happy to give his valuable advice. his work is faultless .
He is in Brisbane as well.
Thanks Grump
Will do
Steampunk wrote: Oh you've got Ohlins? You must like drugs too!!!
-
- Racing Driver
- Posts: 502
- Joined: Fri Mar 04, 2005 9:26 pm
- Vehicle: ND - 2 GT
- Location: Brisbane, Australia
Shortnose Crank Issue
manga_blue wrote:jcs86 wrote:I am most likely going with a 1600
What do people suggest replacing whilst out of the car?
I was considering the following parts but not sure of genuine or after market.
Crank Bolt
Timing Belt
Water Pump
Drive Belts
Clutch
Rear Seal
Nothing else springs to mind..
![]()
Crank Bolt + Woodruff key - Genuine
Timing Belt pulley and/or Crank Pulley boss, if keyways spread at all - Genuine
Timing Belt , idlers, tension spring, cam seals, front oil seal, water pump - aftermarket kit
Drive Belts - aftermarket
Clutch - Exedy Sports
Rear Seal - Genuine or good quality aftermarket
CAS O-ring at back of exhaust cam on NA6(?) - aftermarket
Check all the main coolant hoses - aftermarket
Replace all the other little coolant water hoses that lurk around the front, back and sides of the motor - aftermarket and cheapest by the meter.
Check clutch slave cylinder - aftermarket
Check gearbox front seal - genuine (?)
Do the cam seals as well. I have tools for removing and putting the crank and cam seals back in if you want to borrow them.
Andrew.


Previously, White 95 NA 1.8 Hard Top,Stock standard
Now, 2016 Fiat 500x, 2014 Fiat 500, 2015 ND GT 2.0
Now, 2016 Fiat 500x, 2014 Fiat 500, 2015 ND GT 2.0
- corners
- Racing Driver
- Posts: 1127
- Joined: Mon Aug 20, 2007 1:33 pm
- Vehicle: ND - Supercharged
- Location: Brisbane, QLD
Shortnose Crank Issue
Picked up a longnose 1600 yesterday!!
Now to organise a rebuild.
Now to organise a rebuild.
Steampunk wrote: Oh you've got Ohlins? You must like drugs too!!!
-
- Driver
- Posts: 51
- Joined: Wed Feb 25, 2009 11:12 pm
- Vehicle: ND - 2
- Location: Köln
Shortnose Crank Issue
ampz wrote:The CAS (crank angle sensor) is different between the 1.6 and 1.8 ecus.
The signal starts to differ @ higher rpm's, on the na6 the signal gets way noisy up there (shifts phase is the best way to describe it) and the ecu reads the sync differently.
I am pretty sure the 1.8 cas is different internally (hall effect and not optical) which sends a slightly different signal, which confuses the ecu.
Is this the actual root cause of the 5000rpm issue?
Most of the "guides" i have read require you to fit the 1.6 CAS to the BP engine, via removal of a blanking plate on the exhaust CAM.
Then you would get 1.6 CAS sending signal to 1.6 ECU.
The dyno told the story as the 1.8 injectors were just not putting fuel in after 5,000 rpm.
What was the duty cycle at this time? Was it > 95% or was it say 50% but with a heavily distorted waveform?
Is there an impedance difference between 1.8 and 1.6 injectors?
Small wires make big fuses.
Return to “MX5 Engines, Transmission & Final Drive”
Who is online
Users browsing this forum: No registered users and 5 guests