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MaxiBoost
07-10-12, 14:15
hi
why this crank`s main bearings have more than 2 oil holes?
do you know ?

this is a 2.0 16V crank (Im buy, its used)
but normally main bearings have 2 hole
this is 4 per main bearing

is it good or bad
what are you think ?
??


http://f1210.hizliresim.com/12/7/drb8s.jpg

http://f1210.hizliresim.com/12/7/drb97.jpg
Evodelta
07-10-12, 17:54
Follow the holes with a piece of wire and see where they go.
It's interesting, what car/engine is it from?
1NRO
07-10-12, 17:59
"Follow the holes with a piece of wire and see where they go."

:rofl: All the way back to the sump!

Looks like a Croma crank to me. They have no oil squirters or balance shafts in that engine.
MaxiBoost
07-10-12, 18:26
"Follow the holes with a piece of wire and see where they go."

:rofl: All the way back to the sump!

Looks like a Croma crank to me. They have no oil squirters or balance shafts in that engine.

I dont know which model cars from
but is this holes reduced oil pressure on my Q4 ?
1NRO
07-10-12, 18:33
If your clearances are ok there should be no problems.
MaxiBoost
07-10-12, 18:41
strength ?

maybe more hole more weak?
1NRO
07-10-12, 18:43
Nope, strength will be fine.
Steve Webb
07-10-12, 19:35
Vibration?

(Just so we cover all bases :wink:)
1NRO
07-10-12, 19:38
:lol-052:nope, vibration should be no worse that a usual 4 cyl.
MaxiBoost
08-10-12, 03:44
Nope, strength will be fine.

are you sure? :)
think 8 hole per channel not 4 ?
or 16 hole ?

all the same strength ?
1NRO
08-10-12, 05:41
It'll be as near as makes little difference.

Usually the weakest area on the crank is the radius at the edge of the journals, pretty much the same for all cranks. In this area the Fiat/Lancia/Alfa crank scores well, we have plenty of meat there so a strong crank when compared to others.
MaxiBoost
08-10-12, 08:00
yes but Im very hesitate, I hope you understand me
I can not starting engine rebuild now

Send a mail to guy croft too
Im wait his answer
Steve Webb
08-10-12, 08:48
Like with all metal components, the weak parts are at joints, cutouts and sharp edges\bends.
Even with the extra holes I would have imagined that the crank would fail at the edge of one of the bearing journals.
MaxiBoost
08-10-12, 15:58
this is the guy croft`s answer

Hi Hakan

that crank is OK - they just reduced the number of oil holes in the later engines for cost reasons,

sincerely,
Steve Webb
08-10-12, 17:08
this is the guy croft`s answer

Hi Hakan

that crank is OK - they just reduced the number of oil holes in the later engines for cost reasons,

sincerely,


See, you can trust us. :wave:
MaxiBoost
09-10-12, 03:56
http://www.turbo124.com/forum/viewtopic.php?f=2&t=11216&p=135116#p135116
corriedw
10-10-12, 15:45
A main bearing have a groove in the middle of the shell. The oil flow from the block through that groove to the hole in the crank that must take the oil to the journal. This is needed because the crank turn and the hole in the crank is always in a different position. Between the holes you will see a darker mark where the oil flowed. I can only presume that Lancia decided that if the distance through the groove is shorter, the oil supply will be better.

What is more strange is the two holes in the journals. on a worn engine this will cause oil loss on the first bearings and the last in the line will run dry. In cases where a crank is cross drilled for better lubrication, the old hole will normally be plugged, to put all the oil through the new hole.