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Hi,

My brothers RB25DET is still playing silly buggers with us.

it has a missfire.. tends to looses cylinders and blows lots of white smoke (when the car is hot or cold) and when idling and under some or heavy accelleration

we took the rocker covers off today and found that cylinder 6 is dry and has a low compression of 50 - 75 not sure what thats measured in i think its 600kpa or somthing like that.... any way we blocked it up with a screw driver and kicked it over (no start just kicked it) and when its fully closed (the hole were the spark plug goes in) it doesnt fire no compression... but when you just rest it in their (screw driver) it goes pshhtt pshht saying their compression... (weird) and way were check cylinder 1 and 2 and they were coverd in oil.... the worst thing is that its blowing white smoke and when you kick it over lots of white smoke (burnt oil smell) comes out of the back of the block through the cam shaft were thinking their could be a hole in the block or somthing because when you listen carefuly you can here it going chuff chuff chuff as if its going going down to the sump and coming back through the top ?

i've got some photos to show you were its coming out of hope you guys can help becuase we carnt drive it on boost any more because on cylinder 6 were the spark plug screws in the top of the thread in the block is gone and the spark plug doesnt go in very well!!!

Thanks,

Cameron

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Sounds like time for a new / rebuilt engine. I would hazard a guess that 1 or more pistons have been damaged somehow, and the oil smell you are getting is from 'blow-by' (as the piston comes up on compression stroke, the air/fuel mixture escapes past the rings and pressurises the sump).

How are the spark plugs? Are they also covered in oil?

Your description suggests that #6 cam journal is running dry - that suggests problems with the oil pump.

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(sparkplugs): After a while say couple of days from being in cylinder 6 it would get a bit of oil on it but we tested it stuck it in kicked it over let it start and it run for about 5 mins but the plug was bone dry and had little to none oil on it.

the spark plugs were firing good.

what can you surgest we can do ?

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guys its totally f*(ked now i think...

on idle its just pouring out so much if you leave it idling for 2 mins and theirs so much smoke it intoxicates you!!!

when accellerating you carnt see behind you its just white smoke ! :)

number 6 cylinder has heaps oil in it.

also it went bang again today and it wasent a back fire... ? sounded like the piston blow up ! but it was making funny noises like somthing ratteling through the engine, turbo an exhaust (maby some of the blow up piston ?)

we think its a cracked head.

what solutions can we take ?

cheers,

Cameron

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Are you for real?

LOL @ Steve.

Here's a checklist:

1. STOP DRIVING THE PHUQQIN' CAR!!!

You've probably screwed up heaps of stuff. You're beating Brendan for sheer effort (!!!)

You've probably carked the head, valves, rods, pistons and if you're terribly unlucky, the turbo.

2. You either need a half cut motor or a full rebuild -> tow it to the shop of your choice.

3. Pay up heaps of $$$

T.

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Cameron, i'll just tell you what the others have and what you don't want to hear. I had the same problem 3 months ago. Started with white smoke out the back after boosting up. Gradually got worse until the problem was as you described (constant white cloud in the rear vision mirror, even at idle). Compression was down in cylinder 5 and low in another. The motor's being machined at the moment with forgies going back in soon to be safer. The only upside is that you can strengthen the whole lot while you're there if you need a rebuild.

As blind_elk said, the first thing you need is a leak down test and also check if there's much oil coming out the breather pipe at the top of your rocker cover.

Hate to say it but i don't think it looks good.

Good luck anyways mate.

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we would love to put an rb26dett in it but the problem is we just bought the car a couple mths ago. (and dont have 7k for one)

so it looks like either a rebuild or new motor ?

were taking it to a mechanic tonight and get it checked out !

i will take some photos and post them up if we take the head off....

what do use reckon RB26dett ? Rb25det or rebuild ?

a rebuild would be good but consideing i live up far north qld no one deals with skylines or rb engines :D

Thanks for all your help guys,

Cameron

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if you rebuild, you will have essentially a new engine. the other way of going is get RIPS to send you one of his RB30DET packages. will bold up and for 3.5k(AUD) delivered, is a pretty good way to go, then you can sell your old motor. Several guys in NZ have these, and I have heard only good things from those on here that have used/are using his engines. Alot more torque than an RB26, and probably cheaper than a rebuilt RB25 unless you do the work yourself

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um... you were posting about this two weeks ago and you continued to try and drive it?!..

Sometimes it does pay to listen to people's advice: http://www.skylinesaustralia.com/forums/sh...ead.php?t=34256

well now you've probably done more damage.. to the head as well most likely = more money for you. Just get a whole new engine, I think you may need it.

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Joel, he doesnt use forged internals on the basic package, but can fit them too at added cost of course.

He has run one of his basic RB30DET packages in his drag car, and with a 50? shot of nos, pulled 10s in an R32 GTS4

If you do a search for RIPS a thread he started a while back about running 10s will show up and give links to dynos and more info.

He doesnt have a website that I know of, but he does have an e-mail address.

His engine packages dont include the turbo, but from memory they include plenum and stock manifold which is what he is using (as mentioned) in his R32.

RB30DET good for drag racing? very much so.

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Mine wasn't pissing out that much smoke - And I did stop after the damage was done.........

If he can beat 5 busted pistons, I'll be impressed ! ! ! !

LOL @ Steve.

Here's a checklist:

1. STOP DRIVING THE PHUQQIN' CAR!!!

You've probably screwed up heaps of stuff. You're beating Brendan for sheer effort (!!!)

You've probably carked the head, valves, rods, pistons and if you're terribly unlucky, the turbo.

2. You either need a half cut motor or a full rebuild -> tow it to the shop of your choice.

3. Pay up heaps of $$$

T.

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