| Golf Bearing shell query [message #777619] |
Fri, 14 July 2006 14:26 |
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Hi
I am the process of rebuilding the engine on my golf.I mistakenly
ordered big end bearings with oil hole from GSF part number 16195. On
removing my shells they do not have an oil hole.I have been told it is
ok to use these shells in place of the plain ones.Has anybody come
across this before?If it helps my current shells are marked 026701B.
Thanks
Matt
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| Re: Golf Bearing shell query [message #777620 ] |
Fri, 14 July 2006 14:47 |
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Gti8valve wrote:
> Hi
>
> I am the process of rebuilding the engine on my golf.I mistakenly
> ordered big end bearings with oil hole from GSF part number 16195. On
> removing my shells they do not have an oil hole.I have been told it is
> ok to use these shells in place of the plain ones.Has anybody come
> across this before?If it helps my current shells are marked 026701B.
>
> Thanks
you mean rod bearings? AFAIK the Corrado G60 (which used the oil hole)
and a contemporary Golf 4-cyl. bearings were essentially the samw with
the exception of the oil hole. The G60 apparently had drilled rods for
wristpin lube/piston cooling while the regular engines did not.
nate
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| Re: Golf Bearing shell query [message #777621 ] |
Fri, 14 July 2006 15:03 |
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Hi
yes I mean rod bearings
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| Re: Golf Bearing shell query [message #777629 ] |
Sat, 15 July 2006 00:54 |
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Gti8valve wrote:
> Hi
>
> yes I mean rod bearings
>
Think it through. The oil hole is located off the centerline of the
rod, far from the most-stressed zones. As such the hole has zero real
effect on the surface area of the most important parts of the bearing.
(Even taken as a percentage of the surface area, which would be
worst-case, it's still very small.)
A tiny amount of oil (relatively speaking) will go through the hole and
"lubricate" the wrong side of the bearing. But the surface area of the
hole will be largely blocked by the rod, not to mention held firmly
against it by the bearing crush. So the net effect on oil pressure will
be zero, or the next best thing, unmeasurably small.
If the bearings are otherwise made of the correct materials and built to
the correct dimensions, I'd use them without even thinking about it.
And to dispel a common misunderstanding: The holes put in the bearing
shells and rods have nothing to do with lubrication. *Plenty* of oil is
slung off the crankshaft already. They are there to spray oil on the
underside of the pistons to keep them cooler.
Disclaimer: I'm not a mechanical engineer or anything like that. So
this advice is worth what you paid for it. It's your engine and your
risk to evaluate.
JRE
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| Re: Golf Bearing shell query [message #777630 ] |
Sat, 15 July 2006 02:10 |
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"JRE" <nothing [at] nowhere.com> wrote in message
news:ohVtg.2958$gT3.2323 [at] fe09.lga...
> Gti8valve wrote:
>
>> Hi
>>
>> yes I mean rod bearings
>>
>
> Think it through. The oil hole is located off the centerline of the rod,
> far from the most-stressed zones. As such the hole has zero real effect
> on the surface area of the most important parts of the bearing. (Even
> taken as a percentage of the surface area, which would be worst-case, it's
> still very small.)
>
> A tiny amount of oil (relatively speaking) will go through the hole and
> "lubricate" the wrong side of the bearing. But the surface area of the
> hole will be largely blocked by the rod, not to mention held firmly
> against it by the bearing crush. So the net effect on oil pressure will
> be zero, or the next best thing, unmeasurably small.
>
> If the bearings are otherwise made of the correct materials and built to
> the correct dimensions, I'd use them without even thinking about it.
>
> And to dispel a common misunderstanding: The holes put in the bearing
> shells and rods have nothing to do with lubrication. *Plenty* of oil is
> slung off the crankshaft already. They are there to spray oil on the
> underside of the pistons to keep them cooler.
>
> Disclaimer: I'm not a mechanical engineer or anything like that. So this
> advice is worth what you paid for it. It's your engine and your risk to
> evaluate.
>
> JRE I agree with the above statement . It wont affect anything. The
> sprays are for under the pistons and cylinder walls. They are in the turbo
> diesels too.
If the bearings are dimensionally the same. The only possible thing I could
see wrong, is in theory after the bearings are worn out , and get a gap in
them. like 100-200,000 miles . the oil on the backside may make it easier to
spin the bearing in the rod. But I never heard of anyone spinning VW rod
bearings. I'm no engineer either.
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| Re: Golf Bearing shell query [message #777635 ] |
Sat, 15 July 2006 08:55 |
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Hi Guys
Thanks for your responses.I have since found some else on another forum
that had the same issue and has fitted bearings with an oil hole in
place of plain bearings.So I will proceed.
Matt
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| Re: Golf Bearing shell query [message #777637 ] |
Sat, 15 July 2006 10:28 |
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Most vw engines have jets located in the engine block, which spray oil onto
the undersite of the pistons.
I believe the hole is for lubrication of the wrist pin.
SFC
> shells and rods have nothing to do with lubrication. *Plenty* of oil is
> slung off the crankshaft already. They are there to spray oil on the
> underside of the pistons to keep them cooler.
>
> Disclaimer: I'm not a mechanical engineer or anything like that. So this
> advice is worth what you paid for it. It's your engine and your risk to
> evaluate.
>
> JRE
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