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Hey guys.

I have a mate who's had an RB25/30 made for his R34 skyline a few months ago and the head keeps flooding with oil and catch can is always full.

Any ideas what the problem and possibly solution might be?

His mechanic (the builder) wants to fabricate and install an air oil separator...

The build doesn't have any form of assisted oil return from the head such as a cylinder head oil return kit from head to sump.

I have no idea if the mechanic re did the oil restrictors to help prevent flooding and we have no idea what brands etc are in the engine. The invoice barely detailed anything at all. Same mechanic snapped 2 sets of cams and has had to fix it all twice at his expense due to forgetting but not admitting a spacer or something, can't remember.

Anywho, thought on the dilema? much appreciated guys =)

Cheers

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I'd say he sounds a bit dodgy and wouldnt be using that mechanic anymore

You need to find out what oil pump was installed and go from there. If he hasnt installed restrictors and has installed a bigger pump then that will be your problem

It could really be a number of things, you need to go pry some information out of him

Your options are limited without pulling the engine out. Ideally oil control needs to start with the build before the block is cleaned! Read the first few and last few (or all if you have the inclination) pages of this thread:

http://www.skylinesaustralia.com/forums/topic/110680-oil-control-in-rbs-for-circuit-drag-or-drift/page__hl__sk+oil+control

An oil air seperator really is an ambulance at the bottom of the cliff at this stage and won't solve the problem of the pump potentially emptying your sump.

I had the same problem. Solution was pull engine fit 2x 1.0mm restrictors and breathers from sump to catch can (not to back of head - that does either little at best and probably nothing usefull).

Thanks guys, just got him to go nag his mechanic for info, im thinking he's forgot the restrictors.

Head is running custom 274 HKS cams, solid lifters, upgraded springs etc and im pretty sure the VCT / VVT is still being used

If its got both oil feeds still feeding oil to the head then that will be a big part of your problem. Solid heads need far less oil then hydraulic.

I would Def think twice about going back to that engine builder. Sounds like it was just slapped together with no real thought put into it

So his mechanic said the following:

For f**k sakes Kelvin, f*****g listen to me, it has NOTHING to do with the pump or restrictors! How many f*****g RB engines have I built? F*****g told you id explain it for the 10th time! Go blow up your engine then!!!

All that from asking what pump was in it. Is it so hard to tell someone what parts are in your engine or what was done during the build...

So is the "mechanic" suggesting its normal to empty your sump out via the cam cover breathers? Usually this problem just arises at WOT so only on the dyno or the track so if your mate is getting this happening on the street then if he ever ventures on to the track he has a very real possibility of running out of oil pressure not to mention making a mess of his engine and dropping oil on the track.

Where / how is the vvt being supplied with oil.

Have seen people connect a -4 braided line from the oil pressure port directly into the head with no restrictors to feed the vct .

Does the oil pressure drop when vct is activated?

Just another option

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