Drilling And Tapping Feed/return In Series 1 Rb30 Block

[leeroy_25]

I have started work on my RB30 block which will end life with and R26 head and singel turbo.. The one I am using came without the provisions for the oil feed and return already in the block. The water feed is however there. The oil feed hole is tapped into the block with a hole about 4-5mm diameter going down inside the block, after about 3.25 inches this appears blanked off. I have another block with the feed hole already in and this appears about 5.5 inchs deep before it stops and presumably enters the other side of the block by the oil filter. Can someone tell me how deep I need to drill to open the hole through to create the oil feed and what size should it be. Also what size should the threads be tapped for the oil feed and return. I was considering the option of running a feed from the oil pressure switch. What have other people done with their blocks with out the feeds already in?

Thank you

Lee

[psi]

Dont ya just love RB blocks!

Yes, not all the blocks have the oil passages that go through! I have seen this before in my wifes old VL. It had me stumped for awhile.. So I just 'T'ed into the oil pressure switch on the other side of the block and got oil from there and screwed the oil pressure switch back in. Boom shuck a luck, Turbo had oil and no idiot lights glowing in the dash.

As for drilling out the hole to nowhere.. I nearly did that, I looked at another block that had the oil gallery that went through and I was just going to copy it. My machinest said that I could do it, just drill through until I hit the oil gallery that it was supposed to join up to. But be very careful not to deviate or.. acutually I cant remember why!

Does your block have the oil return just above the sump line like all the other RB's, or does it have a blank 'pad' that looks like it was supposed to be drilled and tapped? If that is the case.. save yourself the pain, get the machinest to do that as well! You can do it if you have the tools, but if you dont, it will probably cost you more to buy the tools and do the job yourself!

[leeroy_25]

Thanks for the reply psi,

I think rather than risk knackering the entire block for a tiny hole I will take a feed from the oil pressure switch! My block is blank on the return hole as well.. I am toying with putting the drain into the sump anyhow.. But I will think about that a bit more yet..

Only other thing I need to check out is the arrangement for the belt tensioners. But that's another thread I think!?

Cheers

Lee

[psi]

there are already threads about the belt tension positions.. have you read the guide?

As for your block, it sounds like you have what is called a series 1 RB30, they are the blocks without all the holes that you really want! No fear, you can either machine them into the block, or by-pass them and get oil from the oil switch and return it into the sump. I did the later in a VL when I converted it a few years back. The best option is to put them in where they really belong.

If you go the later way, make sure you put the oil return as far above the oil level in the sump as you can. the fitting will need to be heat proof and oil proof (like a welded in fitting). Oil leaking there will really get to you!

As for water lines, get them from the plenum side of the engine somewhere and run them to the turbo. Be extra carful to stay away from hot bits and things that can chafe..

happy boosting