Re: alfa-digest V7 #1213 - Alfa Main Bearings

[Mark Dubovick <mutant1@domain.elided>]

Russ,
    I have one more question for you. I've drilled the oil ways through the tops
of the journals(#2 & 4). Do I also have to drill the lines through the casting
perpendicular to the crank shaft. It looks as though the other three have drill
spots which have been filed while these two do not. Also if this is to be done
how do I fill the drilled areas on the side of the casting.
    On one other related issue, should i have the crank heat treated or nitrited?

    Thanks for your help,
    Mark

AlfaNeely@domain.elided wrote:

> In a message dated 12/10/1999 10:09:32 PM Central Standard Time,
> owner-alfa-digest@domain.elided writes:
>
> <<
>  Date: Fri, 10 Dec 1999 20:34:56 -0600
>  From: Mark Dubovick <mutant1@domain.elided>
>  Subject: 1600 engine main bearings
>
>  I have a quick question fo rthose of you who have engine rebuilding
>  experience with the1600cc engines. I just received a set of .10 over
>  bearings for an engine which I am rebuilding and have found the the oil
>  journals on two of the mains do not line up with the oil journals cut in
>  the bearing shells. All of the shells have holes at about 1/3 from
>  either end of the shell while only one of the journals is drilled this
>  way. Two of the other mains have the holes at the center of the
>  journals. I'm talking end to end here not from edge to edge of the
>  bearings. Any help would be appreciated.
>      Thanks,
>      Mark >>
>
>     The groove in the block under the bearing feeds oil along the back side
> to where ever the holes are that allow it to get to the crankshaft side.
> Only the first third and fifth or rear mains have oil supplied to them.  A
> trick to improve oiling on any Alfa four cylinder is to have the block
> drilled to provide oiling to mains number 2 and 4.  Any Alfa I have seen with
> a spun bearing was either number 2 or number 4.  I fact, I have a 1600 block
> in my garage with number 4 main in quite bad shape.
>     If the lack of alignment of the holes really bothers you, drill some that
> do align.  You normally have to do this when you convert to full pressure
> oiling to 2 and 4 mains.  However, it sounds as if all your bearings are
> drilled.  Normally, the two narrow bearings that fit 2 and 4 are not drilled.
>     I am also confused when you say one of the mains in your engine has two
> oil holes spaced about 1/3 of the way in.  The rear main may be drilled that
> way, but I do not think so.  I would have to go look to make sure.
>     Good Luck.
> Ciao,
> Russ Neely
> Oklahoma City

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