5-20 oil

On Mon, 15 Aug 2005 09:17:42 -0500, Steve > wrote:

wrote:
>
>>>I've read that the problems with fully synthetic oil leaking were only a
>>>problem with early synthetics -- that they lacked the chemicals that cause
>>>the seals to swell and hence keep the oil in -- and that this problem no
>>>longer exists, since the formulations have changed.
>>>
>>> > >
>>
>> On a new engine that may be true - but when the rubber is already hard
>> and it's just varnish and sludge keeping the oil in, it's a totally
>> different story. Synth will get out where regular oil has stayed for
>> years.
>
>
>Urban legend. "Sludge and varnish" never keep the oil in.
And you are a mechanic??

wrote:

> On Mon, 15 Aug 2005 09:17:42 -0500, Steve > wrote:
>
>
wrote:
>>
>>
>>>>I've read that the problems with fully synthetic oil leaking were only a
>>>>problem with early synthetics -- that they lacked the chemicals that cause
>>>>the seals to swell and hence keep the oil in -- and that this problem no
>>>>longer exists, since the formulations have changed.
>>>>
>>>>
>>>On a new engine that may be true - but when the rubber is already hard
>>>and it's just varnish and sludge keeping the oil in, it's a totally
>>>different story. Synth will get out where regular oil has stayed for
>>>years.
>>
>>
>>Urban legend. "Sludge and varnish" never keep the oil in.
>
> And you are a mechanic??

No I'm not. But I am an engineer.

Why do you presume to think that "sludge and varnish," which form at
random and have no structural strength of any significant sort, can
actually form a working seal?

Steve wrote:
> wrote:
>
>> On Mon, 15 Aug 2005 09:17:42 -0500, Steve > wrote:
>>
>>
>>> wrote:
>>>
>>>
>>>>> I've read that the problems with fully synthetic oil leaking were
>>>>> only a problem with early synthetics -- that they lacked the
>>>>> chemicals that cause the seals to swell and hence keep the oil in
>>>>> -- and that this problem no longer exists, since the formulations
>>>>> have changed.
>>>>>
>>>>>
>>>> On a new engine that may be true - but when the rubber is already hard
>>>> and it's just varnish and sludge keeping the oil in, it's a totally
>>>> different story. Synth will get out where regular oil has stayed for
>>>> years.
>>>
>>>
>>>
>>> Urban legend. "Sludge and varnish" never keep the oil in.
>>
>>
>> And you are a mechanic??
>
>
> No I'm not. But I am an engineer.
>
> Why do you presume to think that "sludge and varnish," which form at
> random and have no structural strength of any significant sort, can
> actually form a working seal?

I don't know, Steve. I *vividly* remember the one and only time I used
a sudden-flush (kerosene commercial-type flush - came in a quart can) on
a high mileage engine. It was a 1980 Chebby Citation V-6 - the rear
crank seal was the rope-type (not rubber). Before the flush, there were
no leaks. Immediately after the flush - and I mean 5 minutes after the
flush when fresh oil was put in - I laid under the engine with it
running and watched oil streaming out of the rear seal. I have to
believe that the interstices of the rope were sealed up with residue,
and that residue was dissloved away by the flush. A rubber seal isn't
going to have the interstices, but there is that interface between the
seal and the shaft. Now - there's no way an intact soft, non-swolled or
shrunken rubber seal is going to leak, but I could see a special case
where a seal was hard and barely sealing, and a little residue could
make the difference between slight seepage, and steady drip or stream
leakage.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

On Tue, 16 Aug 2005 10:49:25 -0500, Steve > wrote:

wrote:
>
>> On Mon, 15 Aug 2005 09:17:42 -0500, Steve > wrote:
>>
>>
wrote:
>>>
>>>
>>>>>I've read that the problems with fully synthetic oil leaking were only a
>>>>>problem with early synthetics -- that they lacked the chemicals that cause
>>>>>the seals to swell and hence keep the oil in -- and that this problem no
>>>>>longer exists, since the formulations have changed.
>>>>>
>>>>>
>>>>On a new engine that may be true - but when the rubber is already hard
>>>>and it's just varnish and sludge keeping the oil in, it's a totally
>>>>different story. Synth will get out where regular oil has stayed for
>>>>years.
>>>
>>>
>>>Urban legend. "Sludge and varnish" never keep the oil in.
>>
>> And you are a mechanic??
>
>No I'm not. But I am an engineer.


Figures.
Get your hands dirty before you start talking about things you know
nothing about.
>
>Why do you presume to think that "sludge and varnish," which form at
>random and have no structural strength of any significant sort, can
>actually form a working seal?
No presumption at all on my part.
35 years of experience as a mechanic.
Have you ever attempted to remove a few years accumulation of sludge
and varnish from an engine? It can block up oil galleries so tight
that 60PSI of oil pressure cannot force any oil through. And it takes
a whole lot more than a toothbrush to remove it. Try a chisel.

Bill Putney wrote:

> Steve wrote:
>
>> wrote:
>>
>>> On Mon, 15 Aug 2005 09:17:42 -0500, Steve > wrote:
>>>
>>>
>>>> wrote:
>>>>
>>>>
>>>>>> I've read that the problems with fully synthetic oil leaking were
>>>>>> only a problem with early synthetics -- that they lacked the
>>>>>> chemicals that cause the seals to swell and hence keep the oil in
>>>>>> -- and that this problem no longer exists, since the formulations
>>>>>> have changed.
>>>>>>
>>>>>>
>>>>> On a new engine that may be true - but when the rubber is already hard
>>>>> and it's just varnish and sludge keeping the oil in, it's a totally
>>>>> different story. Synth will get out where regular oil has stayed for
>>>>> years.
>>>>
>>>>
>>>>
>>>>
>>>> Urban legend. "Sludge and varnish" never keep the oil in.
>>>
>>>
>>>
>>> And you are a mechanic??
>>
>>
>>
>> No I'm not. But I am an engineer.
>>
>> Why do you presume to think that "sludge and varnish," which form at
>> random and have no structural strength of any significant sort, can
>> actually form a working seal?
>
>
> I don't know, Steve. I *vividly* remember the one and only time I used
> a sudden-flush (kerosene commercial-type flush - came in a quart can) on
> a high mileage engine. It was a 1980 Chebby Citation V-6 - the rear
> crank seal was the rope-type (not rubber). Before the flush, there were
> no leaks. Immediately after the flush - and I mean 5 minutes after the
> flush when fresh oil was put in - I laid under the engine with it
> running and watched oil streaming out of the rear seal. I have to
> believe that the interstices of the rope were sealed up with residue,
> and that residue was dissloved away by the flush. A rubber seal isn't
> going to have the interstices, but there is that interface between the
> seal and the shaft. Now - there's no way an intact soft, non-swolled or
> shrunken rubber seal is going to leak, but I could see a special case
> where a seal was hard and barely sealing, and a little residue could
> make the difference between slight seepage, and steady drip or stream
> leakage.


OK, I'll admit that I can see how a rope-type seal *might* work that
way. But even in that case, my hunch is that the "quick flush" spoo
probably attacked the seal directly, not any embedded gunk in it.

wrote:

>>>>Urban legend. "Sludge and varnish" never keep the oil in.
>>>
>>>And you are a mechanic??
>>
>>No I'm not. But I am an engineer.
>
>
>
> Figures.
> Get your hands dirty before you start talking about things you know
> nothing about.

I don't know you, so I won't brag that I've been inside 5 times as many
engines as you have. So why do you ASSume you've been inside more
engines than I have? Or that I never "get my hands dirty." I'm not a
mechanic, but I've been a car hobbyist for over 20 years.

>
>>Why do you presume to think that "sludge and varnish," which form at
>>random and have no structural strength of any significant sort, can
>>actually form a working seal?
>
> No presumption at all on my part.
> 35 years of experience as a mechanic.
> Have you ever attempted to remove a few years accumulation of sludge
> and varnish from an engine? It can block up oil galleries so tight
> that 60PSI of oil pressure cannot force any oil through. And it takes
> a whole lot more than a toothbrush to remove it. Try a chisel.

Have you ever actually removed that kind of baked-and-burned in place
material (I'd hardly call it 'sludge' or 'varnish' at that point) from a
SEAL? I haven't. Yeah, I've chipped it off the bottom of intake
manifolds where the exhaust crossover shield had dropped off, picked it
out of valve springs that have been overheated until they're blue and
limp, and chiseled it off of heads that were warped from overheating or
had been starved for rocker and valve oiling by clogged pusrhods
(Ford)... but I don't think I've ever removed anything from a SEAL that
you couldn't wipe off with a Q-tip and kerosene.

Bill made a good point about rope-type seals being a different animal,
and so are old-style cork/neoprene matrix gaskets. I'll readily admit
those might theoretically be aided by gunk plugging the pores. But a),
I've switched engines with rope seals and cork/neoprene matrix gaskets
to synthetic without them gushing or even leaking, and b) those are
hardly common items in any engine anybody's going to be dealing with on
a regular basis today. I'm more likely to see them working on an old
flathead 6 or 60s v8 than people with an engine that might call for 5W20
oil.

Because this is the very stuff of usenet:-

- assumptions
- making bold (and bald) statements grounded in the shifting sands of
supposition and vague recollection
- being all-knowing
- rudeness (incl swearing and offensiveness).

But one can still get decent info and have civilised discussions.

DAS

For direct contact replace nospam with schmetterling
---

"Steve" > wrote in message
...
[...]
>> nothing about.
>
> I don't know you, so I won't brag that I've been inside 5 times as many
> engines as you have. So why do you ASSume you've been inside more engines
> than I have? Or that I never "get my hands dirty."

[...]

Bill Putney wrote:

> Steve wrote:
>
>> wrote:
>>
>>> On Mon, 15 Aug 2005 09:17:42 -0500, Steve > wrote:
>>>
>>>
>>>> wrote:
>>>>
>>>>
>>>>>> I've read that the problems with fully synthetic oil leaking were
>>>>>> only a problem with early synthetics -- that they lacked the
>>>>>> chemicals that cause the seals to swell and hence keep the oil in
>>>>>> -- and that this problem no longer exists, since the formulations
>>>>>> have changed.
>>>>>>
>>>>>>
>>>>> On a new engine that may be true - but when the rubber is already hard
>>>>> and it's just varnish and sludge keeping the oil in, it's a totally
>>>>> different story. Synth will get out where regular oil has stayed for
>>>>> years.
>>>>
>>>>
>>>>
>>>>
>>>> Urban legend. "Sludge and varnish" never keep the oil in.
>>>
>>>
>>>
>>> And you are a mechanic??
>>
>>
>>
>> No I'm not. But I am an engineer.
>>
>> Why do you presume to think that "sludge and varnish," which form at
>> random and have no structural strength of any significant sort, can
>> actually form a working seal?
>
>
> I don't know, Steve. I *vividly* remember the one and only time I used
> a sudden-flush (kerosene commercial-type flush - came in a quart can) on
> a high mileage engine. It was a 1980 Chebby Citation V-6 - the rear
> crank seal was the rope-type (not rubber). Before the flush, there were
> no leaks. Immediately after the flush - and I mean 5 minutes after the
> flush when fresh oil was put in - I laid under the engine with it
> running and watched oil streaming out of the rear seal. I have to
> believe that the interstices of the rope were sealed up with residue,
> and that residue was dissloved away by the flush. A rubber seal isn't
> going to have the interstices, but there is that interface between the
> seal and the shaft. Now - there's no way an intact soft, non-swolled or
> shrunken rubber seal is going to leak, but I could see a special case
> where a seal was hard and barely sealing, and a little residue could
> make the difference between slight seepage, and steady drip or stream
> leakage.

Couldn't have been that the flushing brew ruined a seal or two... No,
that could never happen...


Matt

wrote:

> On Tue, 16 Aug 2005 10:49:25 -0500, Steve > wrote:
>
>
wrote:
>>
>>
>>>On Mon, 15 Aug 2005 09:17:42 -0500, Steve > wrote:
>>>
>>>
>>>
wrote:
>>>>
>>>>
>>>>
>>>>>>I've read that the problems with fully synthetic oil leaking were only a
>>>>>>problem with early synthetics -- that they lacked the chemicals that cause
>>>>>>the seals to swell and hence keep the oil in -- and that this problem no
>>>>>>longer exists, since the formulations have changed.
>>>>>>
>>>>>>
>>>>>
>>>>>On a new engine that may be true - but when the rubber is already hard
>>>>>and it's just varnish and sludge keeping the oil in, it's a totally
>>>>>different story. Synth will get out where regular oil has stayed for
>>>>>years.
>>>>
>>>>
>>>>Urban legend. "Sludge and varnish" never keep the oil in.
>>>
>>>And you are a mechanic??
>>
>>No I'm not. But I am an engineer.
>
>
>
> Figures.
> Get your hands dirty before you start talking about things you know
> nothing about.

You mean talking about things like you do?


>>Why do you presume to think that "sludge and varnish," which form at
>>random and have no structural strength of any significant sort, can
>>actually form a working seal?
>
> No presumption at all on my part.

Lots of presumption on your part!


> 35 years of experience as a mechanic.

That hardly makes you an expert on oil seal design and function.


> Have you ever attempted to remove a few years accumulation of sludge
> and varnish from an engine? It can block up oil galleries so tight
> that 60PSI of oil pressure cannot force any oil through. And it takes
> a whole lot more than a toothbrush to remove it. Try a chisel.

A seal and a plug are two different things entirely. You can stuff a
brand new crank seal into and oil passage and likely block it
completely. Likewise, an oil drain plug doesn't make a very good
crankshaft seal, yet it plugs the hole in the oil pan very effectively.
Two totally different concepts. I'll grant you that sludge can make
an effective plug, but it doesn't make an effective seal against a
rotating component.


Matt

Matt Whiting wrote:

> Bill Putney wrote:
>>
>> I don't know, Steve. I *vividly* remember the one and only time I
>> used a sudden-flush (kerosene commercial-type flush - came in a quart
>> can) on a high mileage engine. It was a 1980 Chebby Citation V-6 -
>> the rear crank seal was the rope-type (not rubber). Before the flush,
>> there were no leaks. Immediately after the flush - and I mean 5
>> minutes after the flush when fresh oil was put in - I laid under the
>> engine with it running and watched oil streaming out of the rear
>> seal. I have to believe that the interstices of the rope were sealed
>> up with residue, and that residue was dissloved away by the flush. A
>> rubber seal isn't going to have the interstices, but there is that
>> interface between the seal and the shaft. Now - there's no way an
>> intact soft, non-swolled or shrunken rubber seal is going to leak, but
>> I could see a special case where a seal was hard and barely sealing,
>> and a little residue could make the difference between slight seepage,
>> and steady drip or stream leakage.
>
>
> Couldn't have been that the flushing brew ruined a seal or two... No,
> that could never happen...

Nor would it ever happen that residue/"gunk" embedded in the seal was
dissolved away? I could easily picture semi-liquid/semi flexible
residue, over time, slightly displacing the seal where it met the
crankshaft, and then when dissolved/washed away by the flush, there is a
nice new gap between seal and shaft that previously was filled with the
residue without doing much at all to the seal itself.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')