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Scared Of A Sound Coming From My Rb25det Head.

Inline6Silvia
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Inline6Silvia Newbie

Inline6Silvia

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The car starts up fine but the sound coming from the head is super unnverving. I'm wondering if I have a bent valve or something. I pulled the covers and I saw no sludge or anything. The oil is super clean (I changed it last summer and put 20 miles max on the car. it hardly gets driven). I know its tough to gauge what could be wrong with the vehicle based on sound but here is a video of the noise. Remember this noise is speed dependent.

https://youtu.be/HWnxb16Bfr4

What would my next course of action be? Would a compression test tell me if I have a bent valve or anything? She starts and idles fine and drives fine although the only driving I do is from the end of my driveway back into my garage. Took the valve covers off to see if I saw anything irregular such as sludge or anything but everything is super clean. Like I said since putting this motor together, i've put a maximum of 100 miles on it in 2 years since I finished the car.

I'm from the states but I figure I would ask you guys because you guys see these motors more than we do here in the states. Any info would be much appreciated.

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AngryRB Grand Master

AngryRB

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Sounds like there's two different noises, one when put under sudden load at 0:05 which sounds like a knocking, that noise ive never heard before, the ticking noises I would bet are the lifters , maybe a few have collapsed and not pumping back up..

What was done to the head/motor when built? are you using big camshafts?

Inline6Silvia Newbie

Inline6Silvia

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Brief history of the car. Did fresh internals of the motor. Bottom end was completely worked over. Head is just ported and polished. I put it in the car and life happened and so the car sat more than it was driven. Camshafts are stock. I want my toy back so I am starting to get back into the car. I believe the timing might be a tad off so that could be the knocking you hear. I'm hoping the ticking/knocking is lifters. I plan pulling the lifters this week and seeing if I can clean/revive them. and putting things back together. I also notice that one of the bolts was snapped off the cam angle sensor.

Its been so long since I've worked on the motor that its kind of scaring me to get back into it. Mainly getting the timing right such as getting this at TDC and what not. I've read that I don't want the motor at TDC when I reinstall the cams. It's scary stuff to get in to. The last go around I had someone who knew what he was doing but he has since moved away. It also helped that the motor was out of the car. I'd rather not have to pull the motor if all I am fixing is lifters and timing the motor correctly.

Inline6Silvia Newbie

Inline6Silvia

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Does it have good oil pressure and the right viscosity oil?

I've always put 10w30 in it but might oil pressure gauge is a little suspect (it was used). I'll buy a new one right now. 10w30 is the correct oil I should be using correct?

AngryRB Grand Master

AngryRB

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Posted (edited)

Yeah my thinking is that when the lifters are held under load and sit for long periods is they get bled and stick in position? so will probably need taken out and soaked then pumped up with fresh oil,

There's heaps of threads on lifter problems on here and someone else might have more advise, but if mine id flush, then new oil, get the engine hot and let run for 20mins and see if the lifter free's up, keeping the revs low to avoid damage, but its your call really.

Edited by AngryRB
Inline6Silvia Newbie

Inline6Silvia

Posted
  • Author
Posted (edited)

Yeah my thinking is that when the lifters are held under load and sit for long periods is they get bled and stick in position? so will probably need taken out and soaked then pumped up with fresh oil,

There's heaps of threads on lifter problems on here and someone else might have more advise, but if mine id flush, then new oil, get the engine hot and let run for 20mins and see if the lifter free's up, keeping the revs low to avoid damage, but its your call really.

Yea thats my plan. Ill take the lifters out and work them as best as I can and then reinstall and see where that takes me.

Edited by Inline6Silvia

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