Rb26 Need Help

[blk180]

Ok here go's i had my RB26 built 19000km ago. It has been running well tell last week.

Coming out of a corner i put my foot down and when i let it off the Throttle it stayed reving so i taped it a couple of times. It stop reving i pulled over car sounded like a WRX so i turned if off. Frist thought coils when i went to check this the car wouldnt start. Took it back to the shop which built the motor and they told me that the comp test was 115,120,90,5,0,80 so thats bad. Anyway what would cause this so quick.the shop blamed the head until i said they rebuilt that too. So anyway what ever is wrong with the car was not their fualt LOL.

so could be???

Fuel pump

Rings

head????

what was done to the engine in rebuild

Block was bored, decked and acid bathed

bullet rods

forged pistons

stock crank with jun collar

kings race bearings

N1 oil and water pump

gates timming belt

head has bronze value guides(exhurst side only maybe)

Anyway thats the basics so what would cause the low comp and how dose it happen so qick

Thanks Brad

[skidkid]

If it got a big over rev and no comp. on some cyl. it more than likely has bent valves.

[blk180]

So bent valves can course lose in comp

[CruiseLiner]

a large hole in a piston maybe? was it tuned fairly rich or on the limit? just a thought

that comp test looks like every cylinder is down in pressure, should all be around 150-160ish im pretty sure.

cheers

Edited February 28, 2006 by CruiseLiner

[Craved]

So bent valves can course lose in comp

i bent the exhaust side if No 6 . had 0 comp... cant see it causing a reduction of comp like the other cyclinders

[mjfawke]

i bent the exhaust side if No 6 . had 0 comp... cant see it causing a reduction of comp like the other cyclinders

That would be because some of the valves are only slighly bent.

Bent valves - only for drivers who don't like rev limiters... or for dodgy engines with weak valve springs.

[R31Nismoid]

Anyway thats the basics so what would cause the low comp and how dose it happen so qick

Thanks Brad

Many things that people can only guess.

You'll have to have it properly looked at for the correct answer

[blk180]

Many things that people can only guess.

You'll have to have it properly looked at for the correct answer

Yer know i just wanted to see what people thought it could be. so had a fair idea how much it was going cost.

Rev limiter was set at 8200 car has stock turbos running 11psi boost tuned by a power fc 251rwkws

[Blitz]

I was going to suggest valves also, but those compression test results are terrible.

Time to take the car to another shop and remove the engine for diagnosis.

Best of luck mate

[RPMGTR]

My guess is that she's gobbled the rear exhaust wheel.........its a brave man that puts ceramics back onto a new engine.

[Mik]

My guess is that she's gobbled the rear exhaust wheel.........its a brave man that puts ceramics back onto a new engine.

You beat me to it...doesn't look good.

[hungry6]

Why don't you mention to them to remove the spark plugs and stick a worm camera in there to have a look, without having to remove the head.

This process have save me ten of thousand of dollars in pulling motor/heads off.

[blk180]

My guess is that she's gobbled the rear exhaust wheel.........its a brave man that puts ceramics back onto a new engine.

Yer brave i think word is dum. I will pull the exhurst off tomorrow and have a look as well as check the oil. i was just at the end of my buget last time.

[paulr33]

you may wish to have a read over

http://www.skylinesaustralia.com/forums/in...showtopic=46581

or even post what you find when you do locate the cause

its a journal / log of rb engine failure

[blk180]

Well it apears it was bad fuel or tune.

going to need rebore and new pistons to get back on the road

Be Back Soon Bigger And Better

Thanks for peoples Help Brad

[blk180]

Couple of pics

the most damaged pistons

head damage

closer look at piston 5

[R31Nismoid]

This time change the turbos

[blk180]

yer and the rest anythink that could have course the damage has been changed. tuner,builder,injectors,fuel pumpand turbos

[Guest Mashrock]

thats a good start!

hope it all goes well for you.