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Old Feb 10, 2009 | 12:38 PM
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Default crankshaft??

my bottemend has gone knockin badly ive just bought a used crankshaft but ive just had it regrounded with new shells in it i was just gonna put it but the other day some1 told me not to i dnt know what to do
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Old Feb 10, 2009 | 12:43 PM
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Originally Posted by daves_v7_sti
my bottemend has gone knockin badly ive just bought a used crankshaft but ive just had it regrounded with new shells in it i was just gonna put it but the other day some1 told me not to i dnt know what to do

Simple, DON'T USE IT.

Never ever ever ever use a reground crank on a subaru engine!!!!!

Hope that's clear enough
Buy a new crank and the correct sized bearings.
Buy a new oil modine and a new oil pump too.
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Old Feb 10, 2009 | 12:49 PM
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why cant i use a crank its cost me 250
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Old Feb 10, 2009 | 12:53 PM
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why do ppl say not to recommend getting the crank regrounded
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Old Feb 10, 2009 | 12:54 PM
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Lifted from an email David @ APi sent me:

Originally Posted by David at APi
Can we re-grind the crankshaft ? In our experience re-grinding a Subaru Turbo crank is a poor idea. Once the surface hardening has been removed in the re-grinding process, the crank is ' soft' and will fail again quite quickly. It can of course, be re-hardened, but this is a specialist process and will involve extra cost in re-polishing and straightening the crank after the hardening treatment. Cost saving by then, is minimal. Even so, the gallery plugs that need to be removed when cleaning a crank, are unable to be removed easily on a Subaru crank and the risk of not being able to clean out metal swarf created by grinding is too great
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Old Feb 10, 2009 | 12:57 PM
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theres a place in birmingham halesowen engines said where i had it done the regrounded they sid it would be ok
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Old Feb 10, 2009 | 12:58 PM
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haleowen engines told me it would be ok thats why ive had it done regrounded with new shells
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Old Feb 10, 2009 | 12:59 PM
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Originally Posted by daves_v7_sti
theres a place in birmingham halesowen engines said where i had it done the regrounded they sid it would be ok
Thanks for your money, we dont mind if your engine blows up.... you have to put this in your car, they are not bothered.
Buy a new one

Tony
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Old Feb 10, 2009 | 01:03 PM
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The term is "re-ground", not "regrounded" - if you want to go and fit a re-ground crank into your car, then that is your choice. You asked for reasons why, I gave them.

You could try ringing a few of the usual suspects on here, Api, Enginetuner, Zen, Andy Forrest etc to get their opinion.

I suspect if you rebuild with this crank then you will be doing the same job a few miles down the road.

Your choice buddy
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Old Feb 10, 2009 | 01:07 PM
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Originally Posted by DJ_Jon
The term is "re-ground", not "regrounded" - if you want to go and fit a re-ground crank into your car, then that is your choice. You asked for reasons why, I gave them.

You could try ringing a few of the usual suspects on here, Api, Enginetuner, Zen, Andy Forrest etc to get their opinion.

I suspect if you rebuild with this crank then you will be doing the same job a few miles down the road.

Your choice buddy
Exactamundo,

To the OP, you asked for people's opinions and you've got them.

Perhaps you should of asked them before you spent your money?

There have been loads of threads on here where people have used reground cranks and the engines have gone **** up again fairly quickly.

Feel free to use your reground crank and prove prove us and all the experts wrong.

It's your car and your cash at the end of the day!!
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Old Feb 10, 2009 | 01:19 PM
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Ive been building Impreza engines for 9 years, road, race and rally cars, used a re-ground crank once in the early days, lasted about 800 miles, ive never used one since. I also now of 3 other people that have tried and all failed within a short time.
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Old Feb 10, 2009 | 01:22 PM
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andy at forresters said i can use a reground crank aslong my subaru is standard which it is ?
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Old Feb 10, 2009 | 01:24 PM
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i wana say thank you to all of u for your advise im only asking as ive bought to bottom ends and they have been scrap as iv ebin ripped off
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Old Feb 10, 2009 | 01:36 PM
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can i put a good used crank in
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Old Feb 10, 2009 | 01:47 PM
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Can you guarantee the used crank is good?

You have to ask yourself why has it not been reused?

The only way to know for certain is to buy a new crank.
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Old Feb 10, 2009 | 01:56 PM
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Default crank help

the only reson the crank is good the person i bought it off said 1 of his headgasket has went on his engine so he decided to put a redtop lump in it and stripped the engine to recover some money
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Old Feb 10, 2009 | 02:21 PM
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sorry to hijack this thread i dont have any rod knock but can you tell me for instance if it just started knocking would you still need to change the crank or could you get away with just replacing the bearings if crank was still within specification and i know on some cars if its on the piston end itself can you do the job without taking engine out ie from underneath just so i know in the future thanks.

Last edited by legacytt; Feb 10, 2009 at 02:24 PM.
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Old Feb 10, 2009 | 02:58 PM
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Ive had one crank that was ok after big end failure, very unusual that the bearing doesn't spin and result in metal to metal. If the used crank measures up ok and is straight, then there is no reason not to use it. make sure it's the correct thrust position though!
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Old Feb 10, 2009 | 06:23 PM
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as said above using a reground crank is false economy and will see you spending more in the long run, the £250 you have already spent would have seen you well on the way to a new crank and bearings.
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Old Feb 10, 2009 | 06:29 PM
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for the time it takes do put a crank in and building it all back up why scrimp and save do the job once right , thats my moto
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Old Feb 10, 2009 | 07:13 PM
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Originally Posted by legacytt
sorry to hijack this thread i dont have any rod knock but can you tell me for instance if it just started knocking would you still need to change the crank or could you get away with just replacing the bearings if crank was still within specification and i know on some cars if its on the piston end itself can you do the job without taking engine out ie from underneath just so i know in the future thanks.
pretty sure you cant get to the bearings from underneath it a flat 4 and the block needs to be split to change the bearings,

Last edited by scooby(puppy power); Feb 10, 2009 at 07:15 PM.
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Old Feb 10, 2009 | 07:16 PM
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just re read that lol need to split block to do main bearings not sure about rod bearings
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Old Feb 10, 2009 | 08:19 PM
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thanks for the advise people
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Old Feb 10, 2009 | 09:24 PM
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what should i do ppl
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Old Feb 10, 2009 | 09:31 PM
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Originally Posted by daves_v7_sti
what should i do ppl
For absolute, total peace of mind, discuss with APIDavid. He'll be able to sell you the correct brand new crank and apppropriate sized shells, etc.

Then try and sell on any of the other bits (although it'll be something of moral dilemma, won't it?) .
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Old Feb 10, 2009 | 10:36 PM
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thanks joz
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Old Feb 10, 2009 | 10:38 PM
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Originally Posted by daves_v7_sti
what should i do ppl

Don't rebuild your engine with a re-ground crank, that would be a good start
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Old Feb 10, 2009 | 10:41 PM
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what about a used good crank with original shells
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Old Feb 10, 2009 | 10:48 PM
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Originally Posted by daves_v7_sti
what about a used good crank with original shells
How would you know it's good? Forget it - just get a brand new crank. The relative price of it... comapred to another rebuild... simply isn't worth the ball ache!

You're mindset is all wrong, if you're trying to save a few quid on a new engine build IMHO.

Please, for thr sake of your sanity/pocket, re-read this:-

Originally Posted by David at APi
Can we re-grind the crankshaft ? In our experience re-grinding a Subaru Turbo crank is a poor idea. Once the surface hardening has been removed in the re-grinding process, the crank is ' soft' and will fail again quite quickly. It can of course, be re-hardened, but this is a specialist process and will involve extra cost in re-polishing and straightening the crank after the hardening treatment. Cost saving by then, is minimal. Even so, the gallery plugs that need to be removed when cleaning a crank, are unable to be removed easily on a Subaru crank and the risk of not being able to clean out metal swarf created by grinding is too great



Do it right... Do it ONCE!

Last edited by joz8968; Feb 10, 2009 at 10:55 PM.
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Old Feb 10, 2009 | 10:54 PM
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joz its money i havent got mate thats i suggested the easy option
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