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In an attempt to quantify the major causes of failure in the engines we so much love in our cars I want forum mambers to take a few minutes out to report the failures they have had/witnessed and the circumstances. I suggest the following format to help reveal as much as possible. Pictures are not necessary but can be emailed to me if available. In particular I am interested in RB26 failures but all are necessary to establish the elements of concern. PM your friends to get broadest involvement in this survey on behalf of the forum members.

Engine/Car:

Type of failure:

Factors influencing the failure:

State of tune of the engine:

Suspension and tyres:

Oil used and service interval:

General comments:

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https://www.sau.com.au/forums/topic/46581-report-that-engine-failure/
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OK here's my first one:

Engine/Car: RB25DET GTS25t

Type of failure: Ring lands and turbo compressor oil seal.

Factors influencing the failure: Hot day, suspect load of fuel, hard run in the country, loss of traction over a hill close to redline in third.

State of tune of the engine: As delivered from Japan, generally unknown but had been rebuilt once before as pistons were 0.5mm oversize. Standard computer and timing. 13psi boost. Standard intecooler and 3" cat back exhaust.

Suspension and tyres: RSR springs, 235/255-40-ZR17 tyres.

Oil used and service interval: Shell Helix synthetic (blue)

General comments: Too many things at once to pin the problem. Shell had some problems with fuel quality, the compressor oil seal failed, detonation occurred near redline cresting a small hill and wheelspin occurred. Resulted in huge white/blue oil smoke cloud behind the car. Same result if I tried to accelerate into boost. After a 1 hour cooldown the problem disappeared until 2000km later when severe blowby indicated ringland problems. Turbo was replaced within days of the incident to overcome the oil injestion problem.

Here's my second:

Engine/Car: RB25DET GTS25t

Type of failure: Big end bearings. Pulled down to discover 2 pistons faintly cracked.

Factors influencing the failure: Hot day (38deg) and had been conducting some testing on water sprays into intake and intercooler. The previous engine rebuild had the wrong pistons fitted at 0.5mm OS and was getting excessive blowby. I believe the bearings may have been reused as the car had only travelled 20000km since rebuild. At the last service I saw sparkles in the oil residue indicating bearing deterioration.

State of tune of the engine: Rigoli modded turbo, 11psi boost, cat back 3"

Suspension and tyres: RSR Springs, ZR tyres as above.

Oil used and service interval: Havoline synthetic changed every 5000km with a filter change.

General comments: during the road testing I had experienced detonation (2 aubible pings) when accelerating very close behind a porsche turbo in third on an extremely hot day. I also discovered the engine oil had blown around 300ml out into the catch can and drained this off and replaced it. Several days later on the very hot day I was driving normally in traffic and heard the rattling off the side of a passing van. When I arrived home to park in the garage it was becoming very audible. On pull down the #3 big eng had spun. All bearings were very worn and I discovered the pistons had been installed too small hence the blowby. I won't trust an engine builder again and now do it myself.

Just cause you asked so nicely Geoff ,

R33 GTS25t 4 door Auto

RB25det :Bang:

Blown ringlands on No.1 punched small hole in skirt , & dropped the sparkplug in No. 5 (which ended up in the exhaust wheel of my turbo)

Caused by detonation! most likely due to excessively advanced timing

intake , exhaust, fmic , safc = 280rwhp

275/40/17 rear on 9 1/2" rims , 245/40/17 front , on 8 1/2" rims

Using Havoline Synerngy 10w50 fully synthetic

much more detail at

http://www.skylinesaustralia.com/forums/sh...65&page=1&pp=25

1) RB25DET - 5 busted ringlands

Root cause - Fuel pump hose clamp not done up tight enough, fuel leaked back into the tank instead of going to the rail & injectors, leaned out - then bang (or pop more like)

Running 14 PSI on a hi flow turbo at the time. (about 240 rwkw)

2) RB25DET - Spun Bearing

Probable root cause - hot day, bad oil, bad tune, slipping clutch (maybe) - the Jury is still out on this one......

Running bigger turbo (21 PSI) and about 300 rwkw at the time -

Engine/Car: R32 GTR RB26DETT

Type of failure: 2 pistons and 1 turbo blown

Factors influencing the failure: Faulty AFM

State of tune of the engine: Stock

Suspension and tyres: Stock with R33 GTR rims

Oil used and service interval: Mobil 1. Every 5000kms or every track day.

General comments: Faulty AFM casued motor to lean out and busted pistons 2 and 3. Fragments from pistons went down and smashed turbo. Engine popped at about 70,000km. I didn't get to check the bearing but before then the car hadn't been on the track yet. I'm assuming the car was hardly ever driven in anger as the rotors were thin but no cracks on the drilled holes. Also when it popped it left huge marks on the cylinder walls so a new block was needed.

Engine/Car : R32 GTSt RB20DET

Type of failure : 2 snapped exhaust valves, piston mashed, head mashed.

Factors influencing the failure : Overtightened idler bearing bolt.

State of tune to engine : approx 150 rwkw

Suspension and tyres : std.

Oil used and service interval : Penrite, at 100 000 kms major service by prevvious owner 3000 kms before i bought car.

General comments : 9000 kms after 100k service done just driving home from work, car went bang. A roadside mechanic (who happened to just be parked 30 metres away) heard it let go from that distance. Engine took a couple of seconds to wind down (travelling at 40kms at the time) by time i had come to a complete stop, piston had snapped 2 exhaust vavles, and repeatedly hit the debris into head. 1 dead head, and piston :D

No indication that failure was about to happen. Changing down from 4th to third when it let go. Those indentations in the pistons are the valve reliefs (std). The bolt just clean snapped off level with the block. Upon removing the timing covers, there was a rubber type dust inside and the idler bearing had a discolouration (like it was heated up). I dont know exactly what was replace at the 100,000 km service, ut the previous owner said it was the full service. I bought the car at 103,000 kms....at 109,000 kms it let go....6000 kms later

New motor is rb31det :)

Thanks guys.

B-Man, how old was the engine and what was it treated like for the spun bearing? The fuel pump is also an often overlooked issue so food for thought for us all.

Silver-Arrowz, did you take a look at the other components such as bearings when the engine was stripped? If so what was the mileage and how had the engine been treated up until then?

Bl4cK32, another often overlooked problem. Obviously all the pistons were replaced as I see indentations in the other pistons, or are they standard on a RB20 (it's been a while)? Were there any indicators such as humming noises from the bearing at idle and when cold or was it the bolt that just clean snapped off? Was there any sign of pre-cracking of the bolt (an old dirty/rusty part of the crack and a clean area)? Also new bearings in the rebuild? How did the old ones look at 106,000km?

Just edit your posts if you have the info.

Excellent thread, keep the failures coming! :devil:

Joke or no joke mate, i take serious offence to comments like that. How would you like it if your motor died after driving it 6000kms? Sure i chose to go for a performance motor, but it was the only way i was going to be happy knowing nothing would stuff up again.

Think about what you write mate, cos shit may come back on you one day...

Guys, I appreciate that comment is going to come in, but if it isn't relevant then try to restrain yourself. It may insult some people who are doing us all a huge favour by sharing their grief, and an engine failure is pretty nasty stuff when you have to be without the car for a while and are exposed to huge expense. I appreciate what may have been considered a free bump but I have had the thread stickied while I am in data gathering phase.

Just to clarify, I am gathering as much data as possible so I can establish the causes of the most common failures, when they occur and under what driving/servicing conditions. I will also detail the effected failure elements and when they are likely to fail as well (say after a seizure, what the effect on clutch and gearbox may be). This kind of effort is not inexpensive, having carried it out numerous times before and had to pay for it, so usually it averages $30K-$60K (I'm doing it for love of Skylines). I need good data so please treat the thread and the contributors with some dignity, and feel free to remove any unecessary posts.

I am extremely grateful to those who have shared already.

Engine/Car: RB26DETT/BCNR33

Type of failure: front cylinder (#1) bottom end bearing and rod overheated

Factors influencing the failure: Oil condition and level, new sticky tyres

State of tune of the engine: boost restrictor removed and untuned PowerFC

Suspension and tyres: Stock non-V-Spec, A032R

Oil used and service interval: Ummmm yeah

General comments: Rushed to track after getting tyres and clutch replaced, oil old and not overfilled

B-Man, how old was the engine and what was it treated like for the spun bearing?

 

Not very old - 1000 kms after the rebuild (the first failure) - the motor was run in normally - not constant revs, loaded up, etc - Took it out to eastern creek for a crack at the 1/4 - lots of power , hot day , slipping clutch and still had run in oil in it (I didn't know about that bit) - and the rest is hisory.

Spun bearing, damaged the crank, and conrod so these needed to be replaced. Pistons and rings were fine - so not such a big job - just a new crank, bearings and conrod .

Maybe this should be the official 'SAU B-Man club'!

Engine/Car: 1995 R33 GTSt RB25DET

Type of failure: ringland failure on #6

Factors influencing the failure: overboost on AVC-R

State of tune of the engine: mild

Suspension and tyres: HKS Hypermax II - Bridgestone (F) Toyo Proxies TS1 ®

Oil used and service interval: 5,000km - synthethic

General comments: Just bad luck

T.

Engine/Car: 1993 R32 GTR RB26DETT

Type of failure: Lost oil pressure

Factors influencing the failure: r32 oil pumps are notorious for this problem, running car on dyno at 8000RPM+ didnt help either...

State of tune of the engine: Mild just reeled off 292rwkw at 15psi when tragedy struck..

Mods: HKSt51, 550cc injectors, HKS ROM, 2x 928 bosch fuel pumps, trust drag cooler ect..ect..

Suspension and tyres: full bilstien adjustables and whiteline full kit, kumo 265/35/18's

Oil used and service interval: service every 5000 with penziol synthetic

General comments: the drive engagement on a r32 rb26 is less than half the size of the r33-r34 oil pump engagement... nissan stuffed up and it a common prblem with wear and more power for the landing to crack then throw the gears out the back of the pump and send metal shavings all through the engine.... luckily enough my dyno bloke saw the light actually turning on and shut the engine off and minimalised all damage... still goin a fullhouse rebuild though !!!!

shit

her we go

rb26dett- in r31 gtsx

Type of failure: massive blow by and turbo faliure

Factors influencing the failure:DUNCANS DRIVING... unknown age of engine,DUNCANS DRIVING runing upwards of 1.3 bar for extended periods of time on a standard turbo,DUNCANS DRIVING, car wasnt run above 7k in this state of tune did i mention DUNCANS DRIVING

State of tune of the engine: standard bar jap computer. had the car for 4000km, mobile 1 oil, car has even compression, however has excessive leakdown wont know bearing or bore wear until its appart

Suspension and tyres: full adjustables coil overs, street tyres 225-245/45/17's

General comments: rebuild in progress, will update if there is anything to add

pete

Type of Car: 1993 R33 GTS25T - RB25DET

Type of failure: Damaged Rings on #3 and #6, Valves on 4 and 5, rooted turbo...

Factors influencing the failure: uhhhh few things. Was running a jap tuned Mines ECU, warmish weather 16psi through stock turbo, accidently left oil cap off(idiot), and was flooring it off the toll booth through the M2 trying to race a porche, while the car was pinging off its head...

State of tune of the engine: Front mount, Mines ECU (now gone), exhaust, oil cooler

Suspension and tyres: Whitline coilovers, 225/40R18 front, 25540R18 rear, front and rear torsion bars

Oil used and service interval: 10w 50 every 5000ks

General comments: after all that, am now alot more carefull with my car, don't boost past 12psi, and only in cool weather, and have ditched that dodgy mines ecu... even on stock boost it would occasionally audibly ping. Never get a mines ecu. Ended up fitting a new motor and turbo, now car is as good as gold:)

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