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Discussion Starter #1
I'll be putting pics up in the project section soon, but basically my engine is out now and got the head off this morning.

I was expecting to find a cracked piston and heavy gouges in the cylinder walls, but absolutely nothing! So as No.5 cylinder was full of oil above the piston i'm guessing the rings have gone.

I'm a total amateur as this is the first car engine i've done any in depth work on, so bear with me please :iamwithstupid:

1) If when i get the piston out and it's in one piece with no broken lands, can i just reuse it with new rings? Where do i get the rings from? I'll be checking all the other and repacing their rings an all.

2) Can i get pistons from Nissan if i need them, or do i have to go to one of the specialists on here?

3) If i do find scores and go down the boring out route, can it be done with the crank in place, or does it all have to be removed?


Will get pics up tomorrow of the block and pistons, as not reall sure what i'm looking at yet lol :confused::gay:
 

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Discussion Starter #2
Hmm, i was going to go down the forged route but then changed my mind as i'd need to get the block bored.
Are there any 86mm forged pistons, as i've only seen oversize ones?
 

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#Team Morris - FULLY F**KED
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I'll be putting pics up in the project section soon, but basically my engine is out now and got the head off this morning.

I was expecting to find a cracked piston and heavy gouges in the cylinder walls, but absolutely nothing! So as No.5 cylinder was full of oil above the piston i'm guessing the rings have gone.

I'm a total amateur as this is the first car engine i've done any in depth work on, so bear with me please :iamwithstupid:

1) If when i get the piston out and it's in one piece with no broken lands, can i just reuse it with new rings? Where do i get the rings from? I'll be checking all the other and repacing their rings an all.

2) Can i get pistons from Nissan if i need them, or do i have to go to one of the specialists on here?

3) If i do find scores and go down the boring out route, can it be done with the crank in place, or does it all have to be removed?


Will get pics up tomorrow of the block and pistons, as not reall sure what i'm looking at yet lol :confused::gay:
sure the head gasket wasn't gone between an oil way and the bore?
 

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Discussion Starter #4
Don't think so? I'll have a closer look, but it all seems to be in one piece.

Symtoms were the dipstick getting blown out everytime i drove the car with no smoke behind. Then it started with the blue smoke out the back when i drove it down to strip it last week. Not lost any water either?

Re the forged pistons.....am i right in thinking i'd have to get the block bored no matter what size i went for then? Can this be done with the crank still in?
 

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#Team Morris - FULLY F**KED
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Don't think so? I'll have a closer look, but it all seems to be in one piece.

Symtoms were the dipstick getting blown out everytime i drove the car with no smoke behind. Then it started with the blue smoke out the back when i drove it down to strip it last week. Not lost any water either?

Re the forged pistons.....am i right in thinking i'd have to get the block bored no matter what size i went for then? Can this be done with the crank still in?
sounds like crankcase pressure due to blow by then. cranks gotta come out what ever you do really mate. don't be worried, if the bottom end is standard just put a new set of bearings in. theres loads of info and guides on here, you'l be fine.:)
and while its apart get some forgies!!!
yes you will need a re bore
 

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crank out mate if any work to be done as far as i know. If its out on a stand anyway you would be mad not to get the crank checked for any ware and fit some nice new bearings, about £150 for all the bearings.

Block boring is cheap anyway :)

Could you get away with a re-hone just and new rings and use good condition standard pistons ? Or is it necessary to up the size if even just a rehone is done ?

I have no experience on this so im all ears
 

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no fun in straight lines
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ya can get away with a light hone as long as theres no majour marks on the cyclinder walls and yes ya can just stick a set of rings on and build her up, thats the low cost option, if ya want to go into bigger and better things then your looking at a re bore. but either way i'd be stickinga new set of big end and main shaft bearings into her!!!
 

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Discussion Starter #8
I was expecting to find marks on the cylinders but there's nothing. Only thing i noticed was when turning the engine by hand the No5 piston leaves a thin trail of oil on the cylinder wall as it goes back down.

Now that i have it all out i might as well do it all right i suppose. the plan was to fix and sell, but i know as soon as its fixed and running tip-top again i'll not want to get rid!
 

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think of the future mate, whats your plans. If nothing mad then leave with new rings and a very light hone on the bores and run it in to get good compression, along with big end bearings and check to make sure the crank is all good. Check your pistons very closely too though around the ring lands. You really really dont want to miss a very small crack or weakness...could all be in vain.

If you think 400bhp or more in future then get some forgies, apex performance were selling rb25 ones for a bit less than £500 there,
 

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Discussion Starter #11
Well...the future was to sell it as soon as it was fixed, but i know after all this i'll want to keep it for a wee while longer yet!
Just gonna get new forged pistons now though as i dont want to be taking any risks with the old ones. Along with new bearings and a metal head gasket it should be safe enough i'm thinking.

As long as it all goes back together and runs again i'll be happy lol
 

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I have some scored marks on number 6 cyl, do you think i can get away with a hone ?

The piston ringland is crack, and i can take a chunk out of the piston piece between the first and second ring. Hence why i have a 90 low compression.

the scored mark isn't bad, but you can definitely feel it.

The thing is i have a RB26 crank, and pistons/rings/rods etc for it. I just wanna put those in w/o rebore it and go oversized pistons.
 

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You don't have to forge to run 400+ hp. Mine had standard internals with just a cometic hg and puts out 549bhp on the top map although i run it on the middle one of 489bhp most of the time and it gets abused everytime I used it.
 
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