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Location:
Brisbane, Queensland
Registered:
January 2004
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Re-Use piston rings?
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Tue, 26 April 2005 09:39
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To cut a long story short, my engine needs to be pulled apart after only doing around 91km's.
The rings to be replaced regardless right?
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Location:
Sydney
Registered:
February 2003
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Re: Re-Use piston rings?
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Tue, 26 April 2005 09:48
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im not sure that you have to.
but why wouldnt you.
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Location:
Brisbane, Queensland
Registered:
January 2004
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Re: Re-Use piston rings?
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Tue, 26 April 2005 09:50
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well from what i've been told, as long as the ring gaps are still in order, and i get the cylinder re-honed they should be good to go.
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Location:
Sydney
Registered:
February 2003
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Re: Re-Use piston rings?
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Tue, 26 April 2005 09:52
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but why oh why?
you are going to this much trouble, rings arent that expensive.
with 91000 done, its not like they are brand new
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Location:
Brisbane, Queensland
Registered:
January 2004
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Re: Re-Use piston rings?
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Tue, 26 April 2005 10:03
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no no, this is a brand new rebuilt engine...
with only 91km's on the clock, not 91000.... ninety-one.
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Location:
1st street on the right
Registered:
November 2002
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Re: Re-Use piston rings?
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Tue, 26 April 2005 10:25
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So why are we pulling apart?
If not touching bottom end or removing from bores I'd probably tell you to keep them but if it was me I'd change them if pulling the bottom out regardless.
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Location:
Brisbane, Queensland
Registered:
January 2004
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Re: Re-Use piston rings?
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Tue, 26 April 2005 11:06
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| clubagreenie wrote on Tue, 26 April 2005 20:25 |
So why are we pulling apart?
If not touching bottom end or removing from bores I'd probably tell you to keep them but if it was me I'd change them if pulling the bottom out regardless.
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What we thought was a spun bearing, and the metal has gone thru the entire block. So we need to pull it down clean it all up and start again.
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Location:
Bundaberg, Qld.
Registered:
May 2002
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Re: Re-Use piston rings?
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Tue, 26 April 2005 11:11
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| Quote: |
So why are we pulling apart?
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yea, whats happened?
i had to re-use a set of rings in my mates 4agte in a quick rebuild. honed the block and they bedded in great. these rings had done quite a lot of k's.
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Location:
Brisbane, Queensland
Registered:
January 2004
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Re: Re-Use piston rings?
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Tue, 26 April 2005 11:30
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long story cut short
91km's into run-in, came home and went to hunt down an oil leak i had. Pulled the sump off only to find metal in the sump.
A whole heap of buck passing has occured between the engine builder and myself. As to whos to blame. I'm past the point of caring and getting the thing rebuilt at whoever's expense (yet to be decided). A whole list of reasons of why its happaned.
The mystery is, that none of my bearings have spun, but all show signs of lack of oil pressure. But still there is metal in the sump that has come from somewhere. And has gone thru the whole system, as evident by the now stuffed oil pump and the oil filter catching most of the debris.
All fingers (personally)pointing is the sump i purchased, and failing to clean it out properly, as it was a sump off an engine with a spun bearing. So it appears the ball is in my court.
Now i don't wanna soudn stingy, but the rebuilder says i can re-use the rings fine after the bores are re-honed. I'm after a 2nd opinion before i go there though. Since the whoel thing is being torn down, thats a whole new gasket/seal set, new oil pump, etc...
Personally i'd like to replace the rings, but if there isn't a need to, then i don't see the point.
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Location:
Brisbane
Registered:
February 2003
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Re: Re-Use piston rings?
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Tue, 26 April 2005 12:22
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if some that metal has made it's way up onto the bores then you may have damaged/scored the bores and piston lands.
i'd wait til the engine is apart (you'll need to strip and dip it to ensure all the crap is gone from the oil galleries) before deciding what to do with the bores/pistons/rings.
hopefully the filter let enough oil thru so you don't have wear on cranks surfaces, gudgeon pins, cam bearings and other wearing surfaces.
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Location:
Melbourne
Registered:
May 2002
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Re: Re-Use piston rings?
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Tue, 26 April 2005 12:34
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errrr the oil filter should of got it, worst case your oil pump should be shaged, that could of caused low oil pressure and your barings to suffer, have you plasti gauged the crank?
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Location:
Brisbane, Queensland
Registered:
January 2004
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Re: Re-Use piston rings?
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Tue, 26 April 2005 23:26
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| Allan wrote on Tue, 26 April 2005 22:34 |
errrr the oil filter should of got it, worst case your oil pump should be shaged, that could of caused low oil pressure and your barings to suffer, have you plasti gauged the crank?
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visually there is no major damage to the crank/rods and should linish out. I don't have the engine at the moment the rebuilder has it and is tearing it down as we speak.
Well i had 2 options, either clean up the bearings/crank/rods and stick it all back togther, or pull the whole lot down. I went with the latter. Cause it might save me rebuilding it a 3rd time int he long run.
So as to my rings question?
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Location:
Melbourne
Registered:
May 2002
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Re: Re-Use piston rings?
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Tue, 26 April 2005 23:46
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cost of rings is fuck all
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I Supported Toymods
Location:
Sydney
Registered:
December 2002
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Re: Re-Use piston rings?
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Tue, 26 April 2005 23:58
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Hmm... maybe I can be off assistance.
I have a brand new set of rings that I don't want with the following specs:
Brand: Perfect Circle
Bore: 86.5mm
Top ring: 1.5mm
2nd ring: 1.5mm
Oil Ring: 3mm
I also have a spare oil pump... the spare oil pump has done ~47,000 JDM km's.
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Location:
Brisbane, Queensland
Registered:
January 2004
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Re: Re-Use piston rings?
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Tue, 26 April 2005 23:59
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Thanks toobs, but i've already purchased a new pump. And my pistons are 87mm bore.
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Location:
1st street on the right
Registered:
November 2002
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Re: Re-Use piston rings?
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Wed, 27 April 2005 00:28
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Replace the rings. Get him to split the cost, note his cost.
Ok so the sump should have been clean but as the builder he should have done this regardless. FWIW Pm me his name so I know never to use him. Not that I use anyoneelse anyway.
I'd look hard at the bearings to as they are sloping around in the unfiltered oil.
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Location:
Brisbane, Queensland
Registered:
January 2004
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Re: Re-Use piston rings?
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Wed, 27 April 2005 00:38
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It wasn't the engine builders fault at all. The only thing he rebuilt was the bottom end and the head. I bolted on everything else (sump included).
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On Probation
Location:
Sydney
Registered:
April 2005
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Re: Re-Use piston rings?
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Wed, 27 April 2005 11:07
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I know this feeling well!!!
My first rebuilt engine did 9kms and died. Well it didnt die it just lost oil pressure. So i threw it all out got a new motor and started over.
In my opinion.
Get a virgin block if you can. And use the 86.5mm pistons.
Make sure you have a new oil pump aboove all else.
While its apart get the new rings for sure.
If you have the money buy forged pistons in 86.5mm, h beam rods and Metal head gasket. Toughen it all up!!
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Location:
Brisbane, Queensland
Registered:
January 2004
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Re: Re-Use piston rings?
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Wed, 27 April 2005 11:20
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perhaps you would understand if i told you this was a worked engine.
-arias 87mm pistons
-shotpeened rods
-fully balanced
-kings bearings
-ported head
-arp studs everywhere
-cometic 1mm mhg
-new everything (oil pump, water pump, seals, gaskets)
so im not just gonna 'chuck it away' that would be stupid money wasting process.
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I Supported Toymods
Location:
Sydney
Registered:
December 2002
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Re: Re-Use piston rings?
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Wed, 27 April 2005 13:34
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Are you sure its not your cam journals that have started to be damaged?
Personally I would check out the cams before pulling the head right off... if the cam journals are totalled you might as well go find a new head and start again.
Obviously if this was the case you could re-use your pistons etc.
Also why did you go for 87mm pistons?
I would have bought 86mm forgies for mine if they were more commonly available... I figure such a small increase is not going to make any real power difference.
I would rather have the ability to go a few oversizes if one day the bore is damaged and needs to be bored out again.
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Location:
Brisbane, Queensland
Registered:
January 2004
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Re: Re-Use piston rings?
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Wed, 27 April 2005 20:42
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I didn't even bother taking the cams out. Thats for the rebuilder to do.
And as to why i chose the 87mm pistons. 86mm pistons on a 14year old block probably wouldn't be a good idea. and 86.5mm pistons were another $400 ontop of the price of the 87mm pistons. So i just went the 87mm pistons.
Sure i won't be able to reuse the black later if it comes down to that, but i don't intend to keep this engine forever.
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