drilling main bearings - Page 2

turbolarespider · #16 (**permalink**) 06-22-2005, 01:30 PM

No, not twice as much, just more. Since the path to the bearing is much easier, more oil will get through, hence you will need to pump more oil. I've not done the research, so don't know the exact amount.

That's based on the experience of the people who have done it- my mechanic advised against it on my street car- it would result in lower oil pressure. But we did it on our Turbo as we thought we needed the flow.

Especially since our cylinder pressures were higher...

ossodiseppia · #17 (**permalink**) 06-22-2005, 01:57 PM

Quote:

Originally Posted by turbolarespider

my mechanic advised against it on my street car- it would result in lower oil pressure.

Alex · #18 (**permalink**) 06-23-2005, 09:00 AM

I've also been thinking about doing this modification to my block. Two questions:

1. I have an original 1750 crankshaft dated 1969, still in the factory grease wrapping. Were these nitrided or not? If not, and I drilled and tapped the oil plug holes before having the crank treated, would the process distort the threads enough so that I would just end up tapping them all over again?

2. For this direct oiling modification, would it be advisable to carefully plug the oilways in the crankshaft so that the oil was not "confused" as to whether it should be flowing through the crank or not? In other words, mimicking a solid billet crank?

Alex.

p.s. I blanked off the oil pressure relief valve on the pump for this new engine, my Dad's advice actually - he reckoned it was the only way to keep up the pressure in the old Jaguar XK engine - and since I change the oil every 3000 miles at the very most, dirt build-up etc should not be an issue.

turbolarespider · #19 (**permalink**) 06-23-2005, 10:04 AM

Quote:

Originally Posted by Alex

I've also been thinking about doing this modification to my block. Two questions:

1. I have an original 1750 crankshaft dated 1969, still in the factory grease wrapping. Were these nitrided or not? If not, and I drilled and tapped the oil plug holes before having the crank treated, would the process distort the threads enough so that I would just end up tapping them all over again?

2. For this direct oiling modification, would it be advisable to carefully plug the oilways in the crankshaft so that the oil was not "confused" as to whether it should be flowing through the crank or not? In other words, mimicking a solid billet crank?

Alex.

p.s. I blanked off the oil pressure relief valve on the pump for this new engine, my Dad's advice actually - he reckoned it was the only way to keep up the pressure in the old Jaguar XK engine - and since I change the oil every 3000 miles at the very most, dirt build-up etc should not be an issue.

Alex · #20 (**permalink**) 06-23-2005, 12:59 PM

OK sign me up for Dumb-*** Question of the Month .........

turbolarespider · #21 (**permalink**) 06-23-2005, 02:12 PM

It's ok, I sometimes type faster than I think.

Eric

73gtv · #22 (**permalink**) 06-23-2005, 02:24 PM

Nitriding is a chemical process. Shouldn't distort anything. You might be thinking of shot peening.

VeloceOne · #23 (**permalink**) 06-23-2005, 03:04 PM

Alex,
Why would you blank off the pressure valve? Alfa's do not suffer from pressure or volume problems.....(as proven by the fact that they will run with one or more crank plugs out), in fact you do not want too much pressure.
The relief valve will stop you from having too much pressure and possibly blowing and oil filter.........I would leave it alone bar the fact that I would want to know it is free and not binding. Regards, Ian.

**Wil Painter** · #24 (**permalink**) 06-24-2005, 12:30 PM

I deal with a top crank shop in Southern California. They had me drill & tap before Nitriding, as the process hardens the crank even more and make the drilling/tapping that much more difficult. Tap first, then nitride.
Wil Painter

60sRacer · #25 (**permalink**) 07-03-2005, 03:34 PM

"There's a shop here in Southern California that is jigged up to do this,
--Wil Painter"

Wil, which shop? I'm rebuilding a 2l and am considering this mod, and I'm in Thousand Oaks (So Cal).

Robert

**Wil Painter** · #26 (**permalink**) 07-03-2005, 06:28 PM

Robert:
Engine Machine Service
8416 Osage Ave
Los Angeles, CA 90045
(310) 641-4958
Just north of LAX, cross street to Osage is Manchester, they're to the north 1/2 block
Bill & Dick are great guys and know Alfas well, a tip of the hat to Anthony Rimicci who put me on to their shop
Good Luck
Wil Painter

60sRacer · #27 (**permalink**) 07-03-2005, 09:57 PM

Thanks Wil.

From Thousand Oaks LAX is about 100,000 parked (well slow) cars away, but I'll go a ways for good service. Anybody know of a good Alfa machine shop in San Fernando Valley too? Maybe one that can cross drill crank, and maybe tap aluminum plugs for set screws?

Robert

PSk · #28 (**permalink**) 07-03-2005, 10:08 PM

Quote:

Originally Posted by 60sRacer

Maybe one that can cross drill crank ... Robert

60sRacer · #29 (**permalink**) 07-03-2005, 10:12 PM

Actually, I was just mentally stumbling on the keyboard while I thought of the aluminum plug thing.

Robert

**Wil Painter** · #30 (**permalink**) 07-03-2005, 11:29 PM

Engine Machine Service (EMS) will tap your crank plug holes as well, while your block is getting cross drilled. And yes, the drive is awful. Santos (Anthony's Dad's shop) is in the SF Valley and they use EMS I believe. If you need any other crank work, Castillo's Crankshaft in La Mirada is the place to go, but then you're facing 150,000 parked cars

. EMS and Castillo's send stuff back and forth, however, to save you the extra drive.
Wil Painter