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NA_R33, that's nasty. It has sheared the shaft completely and it is hard to identify if there is a fatigue crack that started the failure. Good luck with the new one.

deadsilly, sounds like they replaced the engine with a secondhand one, correct? Rather than rebuild the broken one? A number of factors have been suggested for reducing oil pressure after running for a while (other than the oil heating and reducing viscosity which is normal anyway). One is the spring in the oil pressure regulator doesn't tolerate the temperature changes (perhaps has been subjected to high temperatures before) and has a reduced transition temperature. I haven't looked into this yet. The oil pump has to be removed to inspect/replace and I have a GTR pump for a little more pressure waiting to go in. The other is the engine is tired and old and due for a rebuild, rings and bearings at least. I would suggest an immediate change to Castrol Formula R 10W60 and see the pressure change. I saw around 6 psi average increase. Mind you though mine also drops pressure after about 15 min to 2.5 bar at idle and 4.5 bar on the track. It is off the scale when cold. Sydneykid and Ben from Racepace Melbourne both use this oil as well.

An oil cooler won't help pressure, just oil longevity in extreme use such as track, and adds extra volume.

As Megalla said, replace the fuel pump as it can often be traced as a major culprit in many engine failures. Do the filter as well. If you get an aftermarket fuel pump ensure enough power is supplied to it byt fitting a good relay and heavy duty wiring from the battery.

Cheers Geoff, i finally got the sucker back on the road yesterday with a pair of hks gtss's, modified fuel rail and malpassi and hks dumps though still a stock front pipe, made 220kw's at all 4 this morning which im stoked about, unfortunately though i cannot mod it for a while as the other party's involved may want to inspect the car for legal reasons, its a bit of a headache but really realeiving the thing works again.

did the ceramic pieces of the turbo get sucked in to the engine ? when my rear turbo let go ( wheel snapped off like yours ) it made a mess inside the engine .

the rear 3 bores were scored , pistons stuffed , even the oil pump was scored .

update on my shitter, turbos are off, strangley only the front turbo spat the exhaust wheel generally its the rear, nengun sent my new ones today so hopefully i wont be making a new post in hear netime soon.

Rear turbo:

3649Repair_023-med.jpg  

Front Turbo:

3649Repair_022-med.jpg

  • 3 weeks later...

ahhh Geoff knows my story but here goes:

Engine/Car:

1993 R33 Skyline RB25DET GTST (around 135,000kms)

Type of failure:

Destroyed 3 pistons

Factors influencing the failure:

Upping boost levels with a Shagged Fuel Pump

Then taking car down to drags - car started to blow black smoke and knock and just sound very sick but still able to limp it around. Compression test showed number 6 was bad.

Limping car around while saving for new engine ..... i decided to take on a Silvia .... R.I.P to my engine .... 3 pistons.

Basically Leadfoot Female driver leaded the RB25 to its final grave.

State of tune of the engine:

Mild .... just upped boost and at that stage a recently installed 3inch zorst.

Suspension and tyres:

17 inch Kumho Supras .... nothing special suspension wise .... lowered onto the bones of its bum.

Oil used and service interval:

every 6 months ..... Redline Oil

General comments:

Oopps! :Oops:

Now rebuilt with Arias Forged pistons ...... im seriously now broke.

okay I guess I will chuck my hat into the ring too...

Engine/Car>

1995 R33 GTSt with 75,000km on the clock

Type of failure>

Spun a big end bearing, all bearings were worn badly down to .5mm... rest of engine was in good condition.

Factors influencing the failure>

Still not 100% sure. I have a couple of ideas...

1. The clutch and flywheel had some heat damage (possibly due to my driving). This could mean heat was the killer, thinning the oil etc... I have no aftermarket guages so it is hard to tell the amount of heat in the motor/drivetrain whilst driving hard...

2. At some point I may have run it a bit low of oil, this combined with high rpms may have starved the bottom end of oil. I did a DECA day and some trips to Calder without overfilling the oil or topping up during the day etc...

3. The bearings were already worn when I bought the car 12 months ago and I just put in the final nail. This theory is hard to believe looking at the condition of it when it arrived from Japan and the condition of the rest of the motor when it was taken out...

4. I don't know... any suggestions? Maybe all of the above???

State of tune>

3.5 inch dump back exhaust, SAFC2 and EBC running about 7psi for daily duties and 10.5psi for fun... approx 170rwkw on the dyno...

Suspension and tyres>

King springs, stock shocks and 225 wide Federal's

Oil used and service interval>

It was changed twice in the 12 months, approx every 5,000kms with whatever performance oil they use at the shop (mechanics experienced with hi po imports)

General comments>

Rebuild completed with Arias forgies, total recondition of head and bottom end... Tomei Poncams didn't make it in time for the build but will go in at a later date... just waiting for the engine to be dropped back in and away we go...

I did want to ask what peoples opinion on the best running in method? I have been told a few different things but just wanted some more opinions?

I did want to ask what peoples opinion on the best running in method? I have been told a few different things but just wanted some more opinions?

For running, I do first 500km with running in oil, with plenty of range drive, eg putting load on the motor with out boosting it and with out going past 3000rpm. If you rings don't seat properly with the running in oil they won't once you do a change to synthetic, so make sure you put load on the motor with out boosting and with out revving too high....

Once you get to about 500 - 550km do a full oil change with straight synthetic, and just take it easy until about 1000km.. And then slow bring it up from then on....

For running, I do first 500km with running in oil, with plenty of range drive, eg putting load on the motor with out boosting it and with out going past 3000rpm. If you rings don't seat properly with the running in oil they won't once you do a change to synthetic, so make sure you put load on the motor with out boosting and with out revving too high....  

Once you get to about 500 - 550km do a full oil change with straight synthetic, and just take it easy until about 1000km.. And then slow bring it up from then on....

Slightly disagree, not with the principle just the generalisation.

It depends on many factors especially what level of work has been done, the amount of honing, the type of rings including the squash/squish if you don't know what this is GOOGLE it... there are a number of threads on here going through it.

As for running in, get an idea FROM your engine builder, if he has NFI or does not come up with one from the start, follow this procedure. Put money back in pocket turn to fac exit and walk!!!!

I recently had my engine rebuilt bu tusing Venolia chrome moly rings. This was honed very coursely due to the ring tensile and the fact that the factory rings had never bedded in properly. The run in procedure was slightly different to above in that it was run in for 500km's using running in oil, which is basically a full mineral based oil. This was then changed to more mineral based oil for the other 500km's. all the time varying the revs and never letting it idle longer than 20 seconds or so. The first 500km's are critical to these engines as the block has a reasonably high silica content. Should you leave it idel for an extended length during the run in procedure you WILL score the bores resulting in the rings NEVER being able to bed in properly.

Also now I use Motul 4100 turbolight as it has been recommended by my engine builder that this SEMI-synthetic is right for my rings, state of tune, which is reasonably stock and the thickness 10-40 is appropriate for the use and temp of the climate. All these things should be discussed with you by you engine builder.

Just thought I would throw a spanner in the mix!!! :werd:

thanks guys...

to be fair my engine builder has recommended a running in method but I just wanted to hear some other opinions

interested in the idling aspect... Bobjones you say not to let it idle for more than like 20 seconds, this would mean at some traffic lights I will have to blip the throttle hear and there to make sure not to score the bores?

and when you say vary the revs, what range are you talking about eg 0-3,000 or just over the whole rev range?

Also putting load on the motor? do you mean driving in a higher gear than normal whilst using low rpms?

anyway thanks for your input guys!

Car - R33 gtst RB25DET 95,000km

Problem - noise in no.1 cylinder when hot at idle, goes away above idle or under load

Cause - bent No1 conrod causing the piston skirt to hit on the oil squirter that hangs into the bore to lube/cool the underside of the piston.

Tune - std engine internals with hi-flow ball bearinged std housing turbo running 12 psi, front mount cooler, full turbo back 3" to 4" exhaust, Wolf 3d computer.

This happened while the car was on the dyno getting the wolf rutuned after the turbo was installed.

Oil was castrol fmx gt3 (or something like that) changed every 5000km with a filter

All the rest of the engine was spot on eg, bearings and pistons

It is still unclear as to what actually caused the problem

Now - due to this little problem the engine now sports rb26 crank and rods with arp rod bolts, oversized venolia forged pistons with genuine nissan N1 rings and bearings. The only mechaning needed for this combo to fit in was a rebore for the oversized pistons. everything else bolted up. You have to love nissan for their thinking with the rb series as so much is interchangeable

thanks guys...

to be fair my engine builder has recommended a running in method but I just wanted to hear some other opinions

interested in the idling aspect... Bobjones you say not to let it idle for more than like 20 seconds, this would mean at some traffic lights I will have to blip the throttle hear and there to make sure not to score the bores?

and when you say vary the revs, what range are you talking about eg 0-3,000 or just over the whole rev range?

Also putting load on the motor? do you mean driving in a higher gear than normal whilst using low rpms?

anyway thanks for your input guys!

Ok now ot answer the questions shortly....

Yes at light vary the revs, no need to blip as you put it, alot of the time the revs with come back down slowly due to the standard ecu (thus why it is better to run an engin ein using the standard ecu)

As for vary the revs yes over the idle to 3,000rpm. Staying at 60 in fourth and not varying the revs will do the same as idling at the lights...

During this time I actually disconnected my turbo timer, and varied the revs slightly in the garage for about 30 or so seconds after a drive. Its does not need anymore than that as you are NOT driving it hard. Keeping it under 3,000 means that you don't score the bores and places load on the engine before the turbo takes too much affect. That si what is meant by load, too much load and it has a detrimental affect, eg going up a hill in fourth with the clutch rattling as the revs are just above idle, some load is good, too much is also bad.

Effectively just drive like miss daisy and you will be fine. I was also running a clutch in at the same time whcih helped with me staying level headed after waiting 2 months to get my car back!!!

Hope that helps

heres a newbie

car - rb20det / hcr32

problem - turbo eater

cause - first turbo weeping head gasket spitting water onto turbo, second turbo bad tuning overheated exhaust wheel which then contacted the housing causing it to jam, third turbo bad tuning again (not my fault i swear) ceramic exhaust wheel shattered on old secondhand turbo...

tune - 3inche exhaust, greddy fmic, hks airpod, and some really dodgy fix up wiring thanks to previous japanese owner...

got the car a month and a half ago with the first turbo already dead and dieing, got new head gasket and brand new t28 hybrid with steel wheels and melted it to the housing, got the 3rd in the mean time turbo (second hand) drove it for about 50kms and pop! got told by my mechanic later that it was only reading about 3 of 15 sensors or something like that, still trying to get to the bottom of whats goin on...

hope to tell some good news soon...

on wises car -

was dodgy japanese

is also running what we think is a non turbo fuel pump and non turbo computer (u can tell aftermarket ones were there)

once it hits 4k rpm it starts to lean out

engine will likely be next as the ring arent looking too good

turns out that in fact there was just an earth in the AFM wiring, which was telling the comp that there was constantly X amount of air flowing past it at all times, there fore it would only inject so much fuel, no matter how many revs the engine was doing. hence the leaning out at 4k and over :)

hopefully all better today :rant:

  • 4 weeks later...

Well, this is long overdue.....

Engine/Car:

RB26DETT in an R32 GTR (91, about 120,000klm)

Type of failure:

Broken. Really broken.

Factors influencing the failure:

Let the wife drive it (man is she going to kill me for this)

State of tune of the engine:

Dead stock

Suspension and tyres:

Stock and rock hard jap spec

Oil used and service interval:

Brand new oil, not sure of brand or grade.

General comments:

1,2 and 6 bores badly scored, same with the pistons. Also had a bent rod on 6 which can't have helped.

The death happened on a very hot day and oil temp went over 120 on ths stock guage, so possibly it was a way too hot oil related failure, with some detination to help out. Interestingly the key that drives the oil pump was VERY badly worn so maybe it wasnt pumping too hard anyway.

Of course the fact that we were racing it may not have helped, but hey a slapping piston is no reason to hold back on the track, right?

Interestingly the supposedly never opened engine had perm marker characters inside the sump and a balanced crank....hmm...

On the other hand, it was nice to see tearing it down wasn't so hard, we pulled apart 2 in 4 hours. I wonder if putting it back together will be so easy?

Ow....to both the engine and the slappin' Kel will give you. Give us an update on the outcome too mate....of the engine rebuild. I don't want to know how much ironing you get as punishment :(

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