crank collar

[minivan_don]

ok ... im 99.9999999 % sure that im correct in saying that i wasnt lucky and that my rb25 has the "problematic" crank collar issue. the flat spot is only 7-8mm ive located a new Jun crank collar already.

[skylinedreams]

yea that looks like the crank collar issue. what series is your 25 I or II

[minivan_don]

s2

[Darius]

Yep. Crank collar issue there, but not nearly as bad as mine or many others that you can find pictures of laying around here at NICO and over at racebread.

[minivan_don]

now the question is what else do i do or replace while ive got the crank out

all day at work, i was thinking of about what it might cost to machine + install forged internals ... im thinking not cheap enough for the moment or unless i make some mad comission at work asap.

[HxC_Nismo]

replace oil pump gasket, timing belt, idler and tensioner pulley if it hasnt been done already. if your on a budget i would replace the main and rod bearings and also have the crank balanced while you have it there for the collar, new head studs and head gasket if it has not been done, the oil orfice in the block to help prevent the rb from starvation of oil. you can reuse the rods and pistons just make sure to mark them from what cylinder they came from.

[nomenai]

yes i

ok ... im 99.9999999 % sure that im correct in saying that i wasnt lucky and that my rb25 has the "problematic" crank collar issue. the flat spot is only 7-8mm ive located a new Jun crank collar already.

I have the same problem w my series2 rb25. I dont now why people said that series 2 rb25 have the long collar

[sean8564]

most defintaly the crank collar.

when i had mine installed the machine shop deep frose the crank and then installed the collar. and i have not had any trouble out of the motor

[minivan_don]

yes crank will be rebalanced once the crank collar is on (btw, the guy who was selling 1 turned out to be a fag and refunded my money at my loss).

ive already ordered an n1 oil and water pump, timing belt idler + tensioner. im working on getting the PE timing belt and tomei oil orifice. i may hold off on installing the orifice as im not sure if im going to pull the head just yet. ive also got a FULL oem gasket kit and arp head studs chilling out under my bed - just in case. i didnt plan to replace the rod/main bearing or rod bolts if im planning to reuse the stock rods/pistons.

what i meant what else i should replace is like going with forged internals (if i happen to find an abundance of money in my bank) but if i did it would tempt me to go with a gt35 vs a gt3076 as well as a few other parts all just more money right...

i found this:

http://cgi.ebay.com/ebaymotors...ZWDVW

from my dirt bike experience, im not a huge fan of weisco pistons (aka SEIZE-CO!!) for that reason. id also have to account for all the machining but everyone and their grandmother would say its a good idea while you got the engine out. ive also found crower rods and cp or je pistons. rod/main bearings are like $300 US and arp main studs $ ??? = LOTS!!!

[minivan_don]

yes iI have the same problem w my series2 rb25. I dont now why people said that series 2 rb25 have the long collar

ive come to the conclusion that ANY rb could have this ... lol. there is no hard evidence confirming any theory so its open. my friend has his s2 rb25 which he will be finding out very soon if he is facing the same thing.

this crank collar issue detured me away from going with an rb26 (other than a higher swap cost) ... and i end up facing it

[Carl H]

s2 r33 rb25 motors with the r34 cas should have the updated crank but even then it can be hazy since some neos that have shown up still have the short snout even tho others dont.only real way to tell is to pull the oil pump off and have a look.

[TwistedGA]

From what Nesar @ jdm-online told me, they will actually cover it under warranty if you only pull the parts needed to see if there is a problem with it... Head removal voids warranty...

Sadly they don't have any clips in stock, but offered me a hellova deal on a r32 motorset. 3850 shipped, which doesn't come with a rb25trans.. which really sucks because McKinney is out of stock on those..

[minivan_don]

i just called up the shop i bought it from and they weren't too familiar with this issue. not much they can do (or almost any other jdm engine seller) can do seeing as they just sell used motors.

[TwistedGA]

I agree, most people carry very little warranty with the clips/sets... I had been bugging them on live support with tons of questions about the motorset, I got lucky when I asked about warranty covering the crank I guess. I will have to return the engine and pay for shipping on a new one if I had to guess, that's probably where they get you on exchanges... I'm praying I get a good crank, I wish you could have had better luck..

Good picture post though, I have had trouble seeing the actual problem on most the other pictures I've seen, these make it very clear what is happening..

[minivan_don]

twistedga,

wouldnt it make more sense for you to keep your existing rb and just get the tomei or jun collar instead of paying for shipping back n forth, or other charges ?? and who's to say the replacement motor wont have the same results.

personally, even if i was offered a exhange on my motor i wouldnt seeing as ive got some hrs into cleaning things up and pulling amost everything off in favor of upgrading parts/sensors/belts/pumps. my $.02 at least ...

[minivan_don]

this is a jun collar that eliminates the crank issue hen pushing much more than stock hp.

[TwistedGA]

I would probably keep the motor and have them give me the cash to have have JUN collar installed and balanced...

It was the fact he said he would take it back if it was a problem. If they pay shipping, I would prolly take that chance, atleast once.. Then for sure do the collar install if it was junk too..