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Need some serious help guys,

My Oil pressure issues have returned. Im only reading around 5psi on idle with cold oil (external electronic oil pressure gauge) running castrol 20W50 GTX to run in the motor.

Anything above idle the pressure comes up eg, it will hit around 70psi at 4k rpm.

Oil pressure sender is mounted on the factory RB25DET oil cooler.

REALLY REALLY want to sort this out as this is a brand new motor that hasnt even been run in yet!!!

Check your pressure with a mechanical master gauge before you worry too much. The fact that it is increasing when you rev the engine is a good sign. If it is using an RB30 pump it should only have around 15psi at idle anyway, increasing once you bump some revs into it. If you have 70psi once you bring the revs up it cant have a big internal leak.

Check your pressure with a mechanical master gauge before you worry too much. The fact that it is increasing when you rev the engine is a good sign. If it is using an RB30 pump it should only have around 15psi at idle anyway, increasing once you bump some revs into it. If you have 70psi once you bring the revs up it cant have a big internal leak.

Yep tried that mate with two different gauges.

Im now wondering if its possible that some gasket glue has somehow made it up into the pressure relief valve and stuck it open ;)

It's probably worth taking the time replace the oil filter and cut the old one to check the paper inside for any bearing metal or contamination. As you said it is a fresh engine and although its a bummer sometimes things dont always go to plan. If its a RB30 pump it wont take much extra clearance to drop the oil pressure especially at idle when pump speed is low. Speaking of pump speed what is your idle rpm? Anyway if its all clear and you dont find anything it will also go a long way to calming your nerves about your new engine, it only takes five minutes after the filters off. If you have just done a filter do a bit more driving just to make sure it has some time to pick anything up that may be there or cut the old one of you still have it.

Dabro

Fixed this problem now guys! thanks for all the help.

It turns out the oil pickup must have been leaking where it bolts to the pump so it was sucking a small amount of air I remember when installing the sump the pickup didnt have an o-ring or gasket so I stupidly tightened it up anyway. I added another bottle of oil making the total 10L this raising the level above the pump and I get healthy oil pressure.

Looks like i'll have to remove the sump order a new o-ring and gasket and fit it.

Main thing is i have pressure now!

I'v got two RB30 blocks. One is from holden origin and the other is out of a silo. they are both different but they both have the oil/water holes drilled and taped?

The silo block is the one i see in all the pictures and is what i bought seperate for my build up (other one is still in my car, was an engine transplant a while ago.)

the only thing i have noticed is that near the rear of the block there is a hole that appears to have been welded shut. this hole doesn't appear to have any use but i'm wondering if this is normal? image below:

(within red circle that hole is full of weld)

weldedholefj4.jpg

the block from a holden doesn't even have this hole, it's just smooth???

ideas?

cheers.

hi guys im new to this site. its the sht,,

i cant seem to find any threads containing wiether or not i can use 26 rods with 26 pistons in an rb30block, i blew bottom end in my 26 and wreked the crank and thort rb30 will be a cheaper option, hoping to use as much as possible outa the 26

the problem is ive never attacked an rb30 b4,,

if possible a compresion figure wuld be awsum

thankyou

Fitted the R?B30det today!

one little problem, I used my rb25 sump and completely forgot about doing the mod to the fins!!! I only realised this as I was just going over the guide by cubes, the sump went on fine just wondering if its crucial to do that mod?

Im in the same boat as you mate! So I feel your pain!

I have to pull my sump off to either replace the oil pump or fit an o-ring to the pick up gasket (possible vacuum leak??). One of the two as far as I can tell is giving me low oil pressure at idle.

I beleive some of the baffles will clash with the crank on the RB25 sump, so It will need to come off and have them ground off. If i remember correctly the exact details are in the PDF

Im in the same boat as you mate! So I feel your pain!

I have to pull my sump off to either replace the oil pump or fit an o-ring to the pick up gasket (possible vacuum leak??). One of the two as far as I can tell is giving me low oil pressure at idle.

I beleive some of the baffles will clash with the crank on the RB25 sump, so It will need to come off and have them ground off. If i remember correctly the exact details are in the PDF

Just fold the fins down, why risk having metal fillings in your sump; yes you can wash/flush the sump but can you be 101% sure you have removed all the fillings?

I personally wouldnt do that Dan, seems a bit too crude for my liking! take it off and grind the fins back!

Al I think you quoted the wrong guy there, I was referring to taking the sump off to fix my Oil pressure issues!

Nope, you're the one talking about using a grinder :glare:

Remove the sump and fold the fins down, makes no difference whether you remove them or fold then, just this way you eliminate any possibility of having any metal fillings in your sump.

what's the disadvantage of using the 3.0 litre sump? them 7l sumps look sexy too.

Nothing.......

I have given (and recieved back) my VL sump to H.E. to convert into a 7ltr sump with full race baffles/windage trays. Sump has now been fitted to the motor and all is great. Hopefully, should have the engine in the car by the end of the week.

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