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hey, started my car this morning almost stalled it never does that, and from the rockercovers more aless the intake sound there is a knocking sound, ive noticed it b4 but it goes away and it came back its inside the engine, anythign to worry about? normal oil pressure, cool water temps?

and if so how much would it cost me to get the bottem end rebuilt? and or the top end? in perth

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yea as i rev it it speeds up and as the revs come down the nose slows down and almost stops, but as it hits idel rpm its back

yo im having a simular issue, i just had a small prang the other day an i start the engine up to keep the oil from going stagnant... bout to get it fixed but im worried it may have hurt the engine although the damage was to the gaurd it didnt touch the engine bay but i dunno.. anyways... point is when my revs go up say 2grand i hear a knocking sound not the ur tipical injectors firing sorta sound but more like a rubbing sound or something more or less... once it goes idle sound goes away, also the fan got pushed back a nudge due to the impact... an literally a nudge an sounds like the sound is coming from the fan / front end of the engine area... so might be the fan itself no idea ill be taking it to get a full service an check up an what not as well as getting the gaurd fixed but yea just thought if any 1 has any ideas?

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U better hope its your lifters, and try not to drive your car too long without getting it checked out. That happened to me, got it serviced but the mech was to much of a noob to find what was wrong, turned out that i did a bearing and broke a rod or something,,the knocking sound became a crucnhing sound. long story short, i did a top and bottom end rebuild, cost about 7k, cz i went and forged everything, but it ended up worth it

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its not coming from the fan, ive spent so much money with my mechanic with my car, and itsb een making the sound since the last service when i had to get it over the pits, and it passed and no one noticed it, im getting greddy emanage installed and dyno'ed so ill see if he can check it out if it blows ill bash a rb26 in it

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Get the knocking sound sorted before you dyno it. Last thing you want is it throwing a rod out the side of the block on the dyno.

If its rising with revs then theres a good chance that you have done a big end bearing, Ive been down this road once myself... never fun...

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Get the knocking sound sorted before you dyno it. Last thing you want is it throwing a rod out the side of the block on the dyno.

If its rising with revs then theres a good chance that you have done a big end bearing, Ive been down this road once myself... never fun...

I second that

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okay, i found some stuff out, when i start it for the first time in a day the noise is there only slightly not very loud, then as i drive around and after about 10-15 mins its pretty much gone, the only thing is when i rev it under the hood and the reves are coming back down there is a slight like rotating sound like if somethign were rotating but off balance sorta thing?

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  • 8 months later...
Get the knocking sound sorted before you dyno it. Last thing you want is it throwing a rod out the side of the block on the dyno.

If its rising with revs then theres a good chance that you have done a big end bearing, Ive been down this road once myself... never fun...

so im reading this article on knocking sounds and stuff and as above you've experienced this? just needed some help, woundering if you could lend some, so i have this slight very hard to hear knock starts at about 1200rpm and falls at 1600rpm sounds almost identical to this guys sound (

) on youtube if you have the time, but a lil less noticable, i dont know if its the timing belts or what =S as its coming from the front section of the engine directly where the timing belts sit ( i think at the front end of the engine?)

and now i have this thought it could be a knocking sound and now sorta seeking advice. and if it is? top or bottom and perhaps you might even know costs?

thnx any advice is much appreciated,

- Dave

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It's not timing belt or tensioner.

I have the same noise. Have had for past maybe 5000km or so.

It isn't bottom end noise, I'm pretty sure of that.

I'm convinced it's in the valvetrain. And if it's this common, I'm going to suggest lifters. But just to be sure I've got consult cable coming.

Top end rebuild of an RB25DET guys - ball parks if you've had one?

Edited by Dorigecko
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If its a knocking sounds that seems like its coming from the rocket cover, or somewhere below, the harmonic balancer might be loose. You can tell if you rev the engine and the tapping increases. Obviously while at higher speeds it will be unnoticable. If this sounds like a familar story you could be ok and its as simple as just tightening the bolt which feeds through the harmonic balancer, may also need to adjusts your belts as well. However if you have left it for to long and its slowly come loose over a period of time which btw will be completly oblivious to you, kind of like a cancer through your bottom end and treating cancer is expensive...aka bottom rebuild. Never the less if your only just noticed you might be ok, as i bloody hope so, but i sugguest you get your car to an expierencd mechine asap, as this is an inherent curse RB's carry, i know i had cancer too :)

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