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Hi everyone.

Just the latest questions i have on my oil issue where oil is going through the inlet on my rb25det.

Basically as known there are breather hoses which from my own knowledge is to pressurise the sump. now at high boost and rpm there is oil coming through these pipes and its end up leading into the intake pipe which is why everytime i close the throttle its sprays out my BOV.

So i said no problem ill block them off like i have done previously on older cars as these are usually only put there because of ADR rules or similar. so idid and it ended up shooting my plug out due to so much pressure building up and popping it off.

So does this mean i possibly have some dodgy cylinders or a cylinder in the car? cracked rings etc etc. i installed a temp catch can from this breather hose and it fills up pretty easy when u give the car a proper hit. should i purchase a proper catch tank or is my engine stuffed.

If i have missed something please ask for any information u need to help with my problem.

Cheers

Callum

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You never plug up the breather hoses otherwise you will overpressurise the crank case and blow seals. What you need to do is install a catch can like you have done, where the oil from the breather hose collects in a can instead of messing up your intake. You might have to do a compression test to see if your motor is still running OK. But it shouldn't fill up as fast as you describe.

RB's breathe heavy at high rpm, so it's not unusual to see oil in the cooler pipes (or filling up catch can) if you've been driving it fairly hard.

like busky2k said, install a catch can, and when you get a chance, do a compression test.

RB's breathe heavy at high rpm, so it's not unusual to see oil in the cooler pipes (or filling up catch can) if you've been driving it fairly hard.

like busky2k said, install a catch can, and when you get a chance, do a compression test.

kool. will do. is it normal for the RB's to still run perfectly smooth which a bad compression. at idle it almost sounds like im running a high lift cam and then its clears as soon as u start to bring up the rpm. Is there a good plumb back catch can u guys would reccommend and where can i purchase online?

Cheers for your help.

bad compression can make the car run poorly.

i'd get a compression test done, just so you can rule out that being a problem before you spend money on parts to fix it. No point doing anything if the rings are gone.

ok so lets just say my rings are gone. whats the best option to fix or replace the engine. is it usually best to just get a front cut that looks to be in good condition or would i be better off fixing my current engine up? from what i understand getting to the piston rings means to basically pull the entire engine apart correct?

Cheers buddy

Fix the current engine up.

The front cut replacement may have spun bearings, the works. You never know.

Rebuild is the best bet.

and what kind of prices are we usually looking at for that and a time frame for off the road time? i may be doing it myself but how much does a tuner or whatever charge to do this kind of job?

Cheers for all the help

Callum

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