RB25det common problems

Hey guys im hopfully going to go RB25DET soon an with that said im trying to do as much research about the motor as possible as i mostly know sr20det, now i came accross the common problem found on the Rb "crank collar issue 'Rearly R32 engine had a crank collar issue where the snout was made to short and oil pump failures happened at high hp and high rpm. the late R32, year 93 and up, fixed the snout and the r33 and r34 had good cranks as well and i think its only the series 2 RB25DET that has this problem, did any RB guys experience this problem or have heard of it,i would like to prepare for the worst and if any body else can add to the common problem list that would be greatly appreciated. :200sx_200sx:

Here are some pics how they resolve the problem:

Before it was corrected.

After it was corrected.

Bud, I have searched till the Earth`s end on the intewebz and found a ton of things that could go wrong.
If I had worried about all of that I would not have gone RB and simply put my Lexus V8 Turbo in..
I have the NEO engine from an importer, rev limit is set at 7800 and boost up to 1.5 bar.
I use my car and the engine works hard.
I have not had a peep or a fart from my engine ! I have a new found respect for Nissan engine`s.

BigKriss wrote:

Bud, I have searched till the Earth`s end on the intewebz and found a ton of things that could go wrong.
If I had worried about all of that I would not have gone RB and simply put my Lexus V8 Turbo in..
I have the NEO engine from an importer, rev limit is set at 7800 and boost up to 1.5 bar.
I use my car and the engine works hard.
I have not had a peep or a fart from my engine ! I have a new found respect for Nissan engine`s.

Ok cool so looks like a rare thing and not as common as i thought any thing any body can add in comcern with the more frequent problems to give me a heads up before i buy the motor.

😉 Just buy a RB25DET NEO.
I had both the old RB25DET and NEO. NEO is a much better motor stock. Stock turbo @ 0.8 bar about 225kw , 350nm.
GT3076R or GT35R + injectors for 300kw+

RB25SX wrote:

😉 Just buy a RB25DET NEO.
I had both the old RB25DET and NEO. NEO is a much better motor stock. Stock turbo @ 0.8 bar about 225kw , 350nm.
GT3076R or GT35R + injectors for 300kw+

+ plenty !

The problem is engines are pricy in cape town a NEO rb is R13500 and im getting normal rb for dirt cheap, but wish i could get the neo 🙂

There is some oil problems. Depends on your use. If you going to be using it stock then I would bother.

The crank collar. Very difficult to say your motor has it fix from the factory unless it is a R34 motor. Seems it kill the oil pump at high revs.

External Oil drain mod. Again depends on use.

Oil restrictors mod. Oil build up in the head holding high revs.

Don't use the N1 oil pump. Use stock or a name brand like tomei or greedy.

rat wrote:

There is some oil problems. Depends on your use. If you going to be using it stock then I would bother.

The crank collar. Very difficult to say your motor has it fix from the factory unless it is a R34 motor. Seems it kill the oil pump at high revs.

External Oil drain mod. Again depends on use.

Oil restrictors mod. Oil build up in the head holding high revs.

Don't use the N1 oil pump. Use stock or a name brand like tomei or greedy.

Thanks @ rat awsome info as for the use for the motor it will be used for everyday,dag,drift so a all rounder.

Then immediately do the oil drain back mod from the back of the head.
My first series one engine spewed oil out of the breathers so bad that I could not see cars behind me..
My NEO was modded before I even had the sump on..it is an R34 Neo with the ally sump so had to modify it for rear wheel use only.

just my 2cents...

any, if not all problems i had with my RB were related to parts around the engine (fan switch, injector seals, gasket etc, minor things), not the engine itself...
mine was basically stock, drove it hard daily for a year and a half, and it just seemed like it wanted more (was only used on the road, so i dont really have any opinions on how it stands up to track abuse and sustained high revs, wich is a different kettle of fish...)
personally ive never had such a "sporty" engine, it just loves to rev and can put the power down early in the rev range till redline without dropping of (all the turbo your running i guess) but the engine feels much better then what you would expect from a 2.5l 6,

to put it into perspective, i just recently acquired an e39 bmw 540i 6 speed daily, (albeit a much heavier car) i keep on comparing the RB to the 4.4l v8, and all i can say is in an sx or any other lighter platform the RB feels like v8 power on steroids, lots of useable torque, can rev till the cows come home, smooth 6cyl power delivery, awesome screamer sound.... oh the sound 😮 i miss it to say the least, bought a v8 to replace it and hardly fills it shoes....(i love the car to bits, just different)

as mentioned, from what i also could surmise, the main issues associated with the rb25 is heavy breathing and oil pump failure, otherwise i would say they can handle quite abit of abuse, use stock oil pump and replace it when you get the engine (and water pump),or if your worried and can afford it ( 😮 ) name brand oil pump

anyway, i know it doesn't really answer the topic, but my opinion

good choice, good luck, you wont be sorry

oh ya, mite as well go neo, worth it for the initial price, unless you plan on changing everything...