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Massive Knock From Rb20

vsute

By vsute,
in Engines & Forced Induction

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vsute Rising Star

vsute

Posted
Posted

Hey guys i am getting a repeditive high note knocking comin form my rb20det which is coming from the centre of the motor. Would this be pistons posably no.3 and 4. is there any chance that it could not be the bottem end?? the knock goes up as the rpm does. The engine it standad running a cooler , rb25 turbo and standard boost. Any ideas ?? its goes to the shop on monday but some advice would be great. Thanks

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BezerkR32 Veteran

BezerkR32

Posted
Posted

Pick engine rpm up then disconnect one coil plug at a time. this will take the load off that cylinder. if knock is less noticable, then it is a 90% chance you have turned a big end bearing or broken a piston in that cylinder.

Hey guys i am getting a repeditive high note knocking comin form my rb20det which is coming from the centre of the motor. Would this be pistons posably no.3 and 4. is there any chance that it could not be the bottem end?? the knock goes up as the rpm does. The engine it standad running a cooler , rb25 turbo and standard boost. Any ideas ?? its goes to the shop on monday but some advice would be great. Thanks
Turbine Collaborator

Turbine

Posted
Posted

If the knock goes away under slight load and returns when you back the throttle off it will be big ends.

Just finished a rebuild on RB20DET that had the oil pump screws work loose dropping oil pressure, destroying big end bearings.

I'd be interested how much that repair is by a shop.

SECURITY Grand Master

SECURITY

Posted
Posted

im thinking lifters too.

is it a light tapping (in the head) noise that gets quicker as the rpm rises or does it sound like theres something loose in your bottom end? if you stick your head under the car can you hear it better?

SECURITY Grand Master

SECURITY

Posted
Posted

theyve pretty much got the same purpose of roller rockers.

they sit right under the cam shafts, its the first thing you'll see once theyre off.

it shouldnt be too expensive to fix, i got away with replacing my lifters that were stuffed without undoing the timing belt tensioner. each lifter cost me $75 each with the SAU discount from nissan, retail is around the $118 mark, someone said that UAS in sydney sell them for $45 each.

str8g Contributor

str8g

Posted
Posted

Hey Ive got an r33 and im getting pretty high knock readings from my power fc, about 60-80. Jus wondering whether it could be my lifters as well. How much did it cost you to get the whole job done. How many lifters are there? I presume 6 for a six cylender?

The Mafia Grand Master

The Mafia

Posted
Posted
Hey Ive got an r33 and im getting pretty high knock readings from my power fc, about 60-80. Jus wondering whether it could be my lifters as well. How much did it cost you to get the whole job done. How many lifters are there? I presume 6 for a six cylender?

umm.. dude have you ever considered that the car might actually be pinging?

....

SECURITY Grand Master

SECURITY

Posted
Posted

you're getting a knock reading, this guy is getting a knock sound.

a tune will fix your knock reading, but as far as i know 60-80 is normal on a pfc? dont quote me.

there are 4 for each cylinder... 2 on the inlet side and 2 on the exhaust side.

the knock sensors are in the block.. they wont detect the lifters in the head.

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