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I suppose that you need something more sophisticated than a hand held drill motor to do this?
 

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FMB,
Adding the two extra oil galleries to the engine, will that cause oil pressure to change? Meaning will there be less pressure and have a different reading on the gauge?
How exactly did you drill the holes, as Ed said you would need something more sophisticated then and hand drill to get the correct angle and depth?

Thanks
 

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If the pump is any good and the engine build good, there will be NO change in oil pressure.
 

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Discussion Starter #24
I suppose that you need something more sophisticated than a hand held drill motor to do this?
Of course, I have used my column drill (photo), but before starting to drill, you have to measure the exact position of the center of the bearings relative to a reference surface (I choose the front face of the block), and translate these measurements to the external surface of the oil gallery, where you have to drill. Also you have to the measure the height of the hole relative to the head or pan surface (theoretically it must be in the middle of the oil gallery, but better double check this) in my case, the hole behind the pressure switch threaded hole doesn't allow me to center the hole so exactly, so as you can see in the pictures the hole is a bit high, but this doesn't supposed any problem.

And the third measurement: the needed depth of the hole, from the center of the bearing to the outer surface of the oil gallery (if I remember well, it was around 90mm).

Once everything is well measured and marked, you have to position the block perfectly horizontal in the drilling machine table, and with a long AND NEW drill (I have used a 5mm diameter one) start to drill patiently using cutting oil (?) until you reach the specified depth.

If you attempt to use an used drill which maybe have been sharpen, it could have a cutting lip bigger than the other, and produce a lateral deviation of the hole, which can ruin your block. You will know if there is any deviation when you made the hole from the center of the bearing surface to reach the lateral hole you already made.

Last thing to do is to drill the bearings, to do that I used a wood support with a semicircle shape cut to hold the bearing aided by some nails at the sides to hold it while drilling.

That's all!!
 

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FMB,
Adding the two extra oil galleries to the engine, will that cause oil pressure to change? Meaning will there be less pressure and have a different reading on the gauge?
How exactly did you drill the holes, as Ed said you would need something more sophisticated then and hand drill to get the correct angle and depth?

Thanks
Unlike FMB, most of us don't have the tools or confidence to do the job correctly, so we rely on experienced machine shops. I use Bill at Apex Machine in Bensenville, IL to drill my blocks for #2/4 direct oiling. Don't recall the price, but it isn't that bad. As for the existing oil passages in the crank, there is no need to plug them. Leaving them allows two options for oil to get to the bearing; directly from the oil galley, or through the drilled passages in the crank. Oil pressure is unaffected by the modification, as the places where pressure bleeds off (rod and main bearing surfaces, cam bearings etc) are unchanged.
 

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Can anyone recommend a shop in NC/SC/GA that can do this job properly?
 

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I'm resurrecting this old thread to keep things in perspective. I drilled out the aluminum plugs in my crank today, and discovered that the holes are threaded..7mm x 1.0. Whaaat? But...they had not been fitted with Allen screws; they had the aluminum plugs in place, except for the one I found in the sump! I'm the 3rd owner of this car and I know both of the previous owners. The head's been off a couple of times but I'm certain the bottom end has been intact for the last 29 years. Anyway..although I buggered the threads a bit removing the plugs, they're cleaning up nicely.
 

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Someone did it! Now put allen plugs in those. Threaded metric?
 

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Just drilled out the aluminium plugs of my 2.0 nord from 1885, and now find what looks like threads in the holes. Is the current best knowledge that all crankshaft holes are actually threaded with M7x1 threads in these late engines?

I guess that saves us the pain of tapping new threads, and it is just a matter of cleaning them up?! And find the M7 allen skrews.
 
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