Earle Horton

If it is a bearing then the crank really, really needs to go to a machine
shop for a check-up. It can be replaced from the bottom though. Plastigage
is a good idea, because the machine shop won't be able to check your bearing
bores, which will still be in the engine. If the plastigage results are not
good, then you open up a whole 'nother can of worms. Usually, this does not
happen, but check anyway.

If it is a wrist pin, then the only way to get to it is with the head and
oil pan off. In that case, anticipate piston damage, need for ring
replacement, etc.

With a "faint knock" maybe it is piston slap that goes away when the engine
is warm, imagination, or gremlins. Hope is a good thing to have, but too
much is probably bad too.

Earle

<JRK58@MSN.COM> wrote in message
news:1135108397.113964.99300@g14g2000cwa.googlegro ups.com...
>
> popeyeball wrote:
> > JK,
> > Hopefully the grit was a non sequitur.
> > I'd consider changing the oil in a short span and checking for grit
> > again. I'd also treat your engine (spend a few extra bucks) to a real
> > oil filter like a Mobil One.
> > Steve in Michigan
>
> I am going to drain into a clean jug with a magnet taped to the bottom.
> I don't want to waste 30 bucks worth of Mobil one 15-50 with less than
> a hundred miles on it. I did use a MB1 filter on the last change. I
> heard a very faint knock again this morning but I didn't have the
> stethoscope on hand. I'm hoping it's nothin but I hate having doubts.
> If it's a wrist pin or bearing can it be repaired from the bottom? The
> rig only has 29K and runs sweet, I think a complete rebuild would be a
> waste. Thanks for the reply.
>
> J Kennedy
>

Earle Horton

If it is a bearing then the crank really, really needs to go to a machine
shop for a check-up. It can be replaced from the bottom though. Plastigage
is a good idea, because the machine shop won't be able to check your bearing
bores, which will still be in the engine. If the plastigage results are not
good, then you open up a whole 'nother can of worms. Usually, this does not
happen, but check anyway.

If it is a wrist pin, then the only way to get to it is with the head and
oil pan off. In that case, anticipate piston damage, need for ring
replacement, etc.

With a "faint knock" maybe it is piston slap that goes away when the engine
is warm, imagination, or gremlins. Hope is a good thing to have, but too
much is probably bad too.

Earle

<JRK58@MSN.COM> wrote in message
news:1135108397.113964.99300@g14g2000cwa.googlegro ups.com...
>
> popeyeball wrote:
> > JK,
> > Hopefully the grit was a non sequitur.
> > I'd consider changing the oil in a short span and checking for grit
> > again. I'd also treat your engine (spend a few extra bucks) to a real
> > oil filter like a Mobil One.
> > Steve in Michigan
>
> I am going to drain into a clean jug with a magnet taped to the bottom.
> I don't want to waste 30 bucks worth of Mobil one 15-50 with less than
> a hundred miles on it. I did use a MB1 filter on the last change. I
> heard a very faint knock again this morning but I didn't have the
> stethoscope on hand. I'm hoping it's nothin but I hate having doubts.
> If it's a wrist pin or bearing can it be repaired from the bottom? The
> rig only has 29K and runs sweet, I think a complete rebuild would be a
> waste. Thanks for the reply.
>
> J Kennedy
>

Earle Horton

If it is a bearing then the crank really, really needs to go to a machine
shop for a check-up. It can be replaced from the bottom though. Plastigage
is a good idea, because the machine shop won't be able to check your bearing
bores, which will still be in the engine. If the plastigage results are not
good, then you open up a whole 'nother can of worms. Usually, this does not
happen, but check anyway.

If it is a wrist pin, then the only way to get to it is with the head and
oil pan off. In that case, anticipate piston damage, need for ring
replacement, etc.

With a "faint knock" maybe it is piston slap that goes away when the engine
is warm, imagination, or gremlins. Hope is a good thing to have, but too
much is probably bad too.

Earle

<JRK58@MSN.COM> wrote in message
news:1135108397.113964.99300@g14g2000cwa.googlegro ups.com...
>
> popeyeball wrote:
> > JK,
> > Hopefully the grit was a non sequitur.
> > I'd consider changing the oil in a short span and checking for grit
> > again. I'd also treat your engine (spend a few extra bucks) to a real
> > oil filter like a Mobil One.
> > Steve in Michigan
>
> I am going to drain into a clean jug with a magnet taped to the bottom.
> I don't want to waste 30 bucks worth of Mobil one 15-50 with less than
> a hundred miles on it. I did use a MB1 filter on the last change. I
> heard a very faint knock again this morning but I didn't have the
> stethoscope on hand. I'm hoping it's nothin but I hate having doubts.
> If it's a wrist pin or bearing can it be repaired from the bottom? The
> rig only has 29K and runs sweet, I think a complete rebuild would be a
> waste. Thanks for the reply.
>
> J Kennedy
>

JRK58@MSN.COM

I heard that a main bearing going out would be pretty loud, increasing
with temperature and a loss of oil pressure. This knock is barely
audible but definitely there.I can't hear it with the hood up, only
sitting in the cab with the doors shut. I have only heard it twice,
both times at a cold start up. It does go away after a minute or so. As
far as the grit goes what could it be? They are very small, black and
magnetic. I guess I will know more when I drain it. Thanks for the
reply.

J Kennedy

JRK58@MSN.COM

I heard that a main bearing going out would be pretty loud, increasing
with temperature and a loss of oil pressure. This knock is barely
audible but definitely there.I can't hear it with the hood up, only
sitting in the cab with the doors shut. I have only heard it twice,
both times at a cold start up. It does go away after a minute or so. As
far as the grit goes what could it be? They are very small, black and
magnetic. I guess I will know more when I drain it. Thanks for the
reply.

J Kennedy

JRK58@MSN.COM

I heard that a main bearing going out would be pretty loud, increasing
with temperature and a loss of oil pressure. This knock is barely
audible but definitely there.I can't hear it with the hood up, only
sitting in the cab with the doors shut. I have only heard it twice,
both times at a cold start up. It does go away after a minute or so. As
far as the grit goes what could it be? They are very small, black and
magnetic. I guess I will know more when I drain it. Thanks for the
reply.

J Kennedy

Hootowl

On 20 Dec 2005 12:15:54 -0800, JRK58@MSN.COM wrote:

>I heard that a main bearing going out would be pretty loud, increasing
>with temperature and a loss of oil pressure. This knock is barely
>audible but definitely there.I can't hear it with the hood up, only
>sitting in the cab with the doors shut. I have only heard it twice,
>both times at a cold start up. It does go away after a minute or so. As
>far as the grit goes what could it be? They are very small, black and
>magnetic. I guess I will know more when I drain it. Thanks for the
>reply.

There is always a little metal in the bottom of an engine or gear
case. A magnetic drain plug will make it more noticeable because it
concentrates it in one small place. That's why there is a fine screen
over the oil pump pick up tube (it protects the gears that actually
pump the oil). I really think you're worrying over nothing. If you
don't hear bearing or piston slap, don't worry.
>
>J Kennedy

Hootowl

On 20 Dec 2005 12:15:54 -0800, JRK58@MSN.COM wrote:

>I heard that a main bearing going out would be pretty loud, increasing
>with temperature and a loss of oil pressure. This knock is barely
>audible but definitely there.I can't hear it with the hood up, only
>sitting in the cab with the doors shut. I have only heard it twice,
>both times at a cold start up. It does go away after a minute or so. As
>far as the grit goes what could it be? They are very small, black and
>magnetic. I guess I will know more when I drain it. Thanks for the
>reply.

There is always a little metal in the bottom of an engine or gear
case. A magnetic drain plug will make it more noticeable because it
concentrates it in one small place. That's why there is a fine screen
over the oil pump pick up tube (it protects the gears that actually
pump the oil). I really think you're worrying over nothing. If you
don't hear bearing or piston slap, don't worry.
>
>J Kennedy

Hootowl

On 20 Dec 2005 12:15:54 -0800, JRK58@MSN.COM wrote:

>I heard that a main bearing going out would be pretty loud, increasing
>with temperature and a loss of oil pressure. This knock is barely
>audible but definitely there.I can't hear it with the hood up, only
>sitting in the cab with the doors shut. I have only heard it twice,
>both times at a cold start up. It does go away after a minute or so. As
>far as the grit goes what could it be? They are very small, black and
>magnetic. I guess I will know more when I drain it. Thanks for the
>reply.

There is always a little metal in the bottom of an engine or gear
case. A magnetic drain plug will make it more noticeable because it
concentrates it in one small place. That's why there is a fine screen
over the oil pump pick up tube (it protects the gears that actually
pump the oil). I really think you're worrying over nothing. If you
don't hear bearing or piston slap, don't worry.
>
>J Kennedy

Hootowl

On 20 Dec 2005 11:53:17 -0800, JRK58@MSN.COM wrote:

>
>popeyeball wrote:
>> JK,
>> Hopefully the grit was a non sequitur.
>> I'd consider changing the oil in a short span and checking for grit
>> again. I'd also treat your engine (spend a few extra bucks) to a real
>> oil filter like a Mobil One.
>> Steve in Michigan
>
>I am going to drain into a clean jug with a magnet taped to the bottom.
>I don't want to waste 30 bucks worth of Mobil one 15-50 with less than
>a hundred miles on it. I did use a MB1 filter on the last change. I
>heard a very faint knock again this morning but I didn't have the
>stethoscope on hand. I'm hoping it's nothin but I hate having doubts.
>If it's a wrist pin or bearing can it be repaired from the bottom? The
>rig only has 29K and runs sweet, I think a complete rebuild would be a
>waste. Thanks for the reply.

Let me repeat, that's common. As long as it stops as the engine
warms, don't worry. I've had it, and both engines went over 150,000
miles farther before they needed an overhaul. And synthetic oil is
usually thinner than petroleum-based oil, and can such noises (and oil
consumption) more noticeable.

Dan
>
>J Kennedy