Slightly off-topic--How to change an oil pressure sending unit?

Mechanic told me the oil pressure sending unit (this is the same as the oil
pressure sensor, right?) was leaking. I checked and yeah, it is wet with
oil but I did not see any drips on the garage floor. Nevertheless this
seems like something I could do myself but I'm having trouble finding
anything on it in my Haynes manual.

How do I find answers to my questions about replacing this unit, mainly,
what torque setting do I use and is there anything unusual I need to know
about changing it? I already figured out I'd need to drain the oil first
and refill it after.

"Ernie Sty" <fake_email@yahoo.com> wrote in message
news:66qdnXStUv7v8tPZnZ2dnUVZ_vGdnZ2d@giganews.com...[color=blue]
> Mechanic told me the oil pressure sending unit (this is the same as the
> oil pressure sensor, right?) was leaking. I checked and yeah, it is wet
> with oil but I did not see any drips on the garage floor. Nevertheless
> this seems like something I could do myself but I'm having trouble finding
> anything on it in my Haynes manual.
>
> How do I find answers to my questions about replacing this unit, mainly,
> what torque setting do I use and is there anything unusual I need to know
> about changing it? I already figured out I'd need to drain the oil first
> and refill it after.[/color]

You don't say what vehicle, but generally, no need to drain the oil.

Just get a new sender, unscrew the old with a pair of pliers, wrap a couple
of loops of teflon tape around the threads of the new sender, and screw it
in as tight as you can by hand (no tools). Start the engine and check for
leaks - if so, turn it in a quarter turn at a time until it stops.

"Mike Harris" <harrisremovethiswest@sbcglobal.net> wrote in message
news:hGu3g.19796$tN3.14799@newssvr27.news.prodigy.net...[color=blue]
> "Ernie Sty" <fake_email@yahoo.com> wrote in message
> news:66qdnXStUv7v8tPZnZ2dnUVZ_vGdnZ2d@giganews.com...[color=green]
>> Mechanic told me the oil pressure sending unit (this is the same as the
>> oil pressure sensor, right?) was leaking. I checked and yeah, it is wet
>> with oil but I did not see any drips on the garage floor. Nevertheless
>> this seems like something I could do myself but I'm having trouble
>> finding anything on it in my Haynes manual.
>>
>> How do I find answers to my questions about replacing this unit, mainly,
>> what torque setting do I use and is there anything unusual I need to know
>> about changing it? I already figured out I'd need to drain the oil first
>> and refill it after.[/color]
>
> You don't say what vehicle, but generally, no need to drain the oil.
>
> Just get a new sender, unscrew the old with a pair of pliers, wrap a
> couple of loops of teflon tape around the threads of the new sender, and
> screw it in as tight as you can by hand (no tools). Start the engine and
> check for leaks - if so, turn it in a quarter turn at a time until it
> stops.[/color]


Thanks! I forgot to mention it's a 1994 Geo Metro with the 3-cyl engine.
That's why it's an OT post. I believe you when you say I don't have to
drain the oil, but am curious as to how it can leak oil if it's above the
oil level? It's located on the back side, and there's no way the engine
could ever generate enough acceleration to slosh the oil back... I suppose
it could happen then I apply the brakes while backing down the driveway...

"Ernie Sty" <fake_email@yahoo.com> wrote in message
news:66qdnXStUv7v8tPZnZ2dnUVZ_vGdnZ2d@giganews.com...[color=blue]
> Mechanic told me the oil pressure sending unit (this is the same as the
> oil pressure sensor, right?) was leaking. I checked and yeah, it is wet
> with oil but I did not see any drips on the garage floor. Nevertheless
> this seems like something I could do myself but I'm having trouble finding
> anything on it in my Haynes manual.
>
> How do I find answers to my questions about replacing this unit, mainly,
> what torque setting do I use and is there anything unusual I need to know
> about changing it? I already figured out I'd need to drain the oil first
> and refill it after.
>[/color]

What kind of car is it? I have to replace the one in my Supra, the TSRM
shows it at the front of the motor, but I'll be dammed if'n I can find it!

"Ernie Sty" <fake_email@yahoo.com> wrote in message
news:2KudnWxOs7gz59PZnZ2dnUVZ_sednZ2d@giganews.com...[color=blue]
> Thanks! I forgot to mention it's a 1994 Geo Metro with the 3-cyl engine.
> That's why it's an OT post. I believe you when you say I don't have to
> drain the oil, but am curious as to how it can leak oil if it's above the
> oil level? It's located on the back side, and there's no way the engine
> could ever generate enough acceleration to slosh the oil back... I
> suppose it could happen then I apply the brakes while backing down the
> driveway...[/color]

Hmmmm. Ever think what an "oil pressure sensor" is actually sensing? Do
you suppose that there might be some sort of pump that puts that oil under
pressure?

"Ernie Sty" <fake_email@yahoo.com> wrote in message
news:2KudnWxOs7gz59PZnZ2dnUVZ_sednZ2d@giganews.com...[color=blue]
>
> "Mike Harris" <harrisremovethiswest@sbcglobal.net> wrote in message
> news:hGu3g.19796$tN3.14799@newssvr27.news.prodigy.net...[color=green]
>> "Ernie Sty" <fake_email@yahoo.com> wrote in message
>> news:66qdnXStUv7v8tPZnZ2dnUVZ_vGdnZ2d@giganews.com...[color=darkred]
>>> Mechanic told me the oil pressure sending unit (this is the same as the
>>> oil pressure sensor, right?) was leaking. I checked and yeah, it is wet
>>> with oil but I did not see any drips on the garage floor. Nevertheless
>>> this seems like something I could do myself but I'm having trouble
>>> finding anything on it in my Haynes manual.
>>>
>>> How do I find answers to my questions about replacing this unit, mainly,
>>> what torque setting do I use and is there anything unusual I need to
>>> know about changing it? I already figured out I'd need to drain the oil
>>> first and refill it after.[/color]
>>
>> You don't say what vehicle, but generally, no need to drain the oil.
>>
>> Just get a new sender, unscrew the old with a pair of pliers, wrap a
>> couple of loops of teflon tape around the threads of the new sender, and
>> screw it in as tight as you can by hand (no tools). Start the engine and
>> check for leaks - if so, turn it in a quarter turn at a time until it
>> stops.[/color]
>
>
> Thanks! I forgot to mention it's a 1994 Geo Metro with the 3-cyl engine.
> That's why it's an OT post. I believe you when you say I don't have to
> drain the oil, but am curious as to how it can leak oil if it's above the
> oil level? It's located on the back side, and there's no way the engine
> could ever generate enough acceleration to slosh the oil back... I
> suppose it could happen then I apply the brakes while backing down the
> driveway...[/color]

The oil pressure sender, as the name implies, senses oil pressure. When the
engine is running, oil is pumped under pressure throughout the engine. In
other words, it is leaking because of the pressure behind it, not because of
the oil level.
--

Ray O
(correct punctuation to reply)

"Mike Harris" <harrisremovethiswest@sbcglobal.net> wrote in message
news:q6v3g.19805$tN3.19539@newssvr27.news.prodigy.net...[color=blue]
> "Ernie Sty" <fake_email@yahoo.com> wrote in message
> news:2KudnWxOs7gz59PZnZ2dnUVZ_sednZ2d@giganews.com...[color=green]
>> Thanks! I forgot to mention it's a 1994 Geo Metro with the 3-cyl engine.
>> That's why it's an OT post. I believe you when you say I don't have to
>> drain the oil, but am curious as to how it can leak oil if it's above the
>> oil level? It's located on the back side, and there's no way the engine
>> could ever generate enough acceleration to slosh the oil back... I
>> suppose it could happen then I apply the brakes while backing down the
>> driveway...[/color]
>
> Hmmmm. Ever think what an "oil pressure sensor" is actually sensing? Do
> you suppose that there might be some sort of pump that puts that oil under
> pressure?[/color]


Yeah, thanks, I am aware that it is under pressure. However if the level of
the fluid level is below the hole, how does it get to the hole? Does the
pressure cause the oil to flow up the side of the crankcase to the pressure
sensor? Does the level rise when it is under pressure?

"Ray O" <rokigawa@tristarassociatesDOTcomn> wrote in message
news:94321$444e802d$44a4a10d$23182@msgid.meganewsservers.com...[color=blue]
>
> "Ernie Sty" <fake_email@yahoo.com> wrote in message
> news:2KudnWxOs7gz59PZnZ2dnUVZ_sednZ2d@giganews.com...[color=green]
>>
>> "Mike Harris" <harrisremovethiswest@sbcglobal.net> wrote in message
>> news:hGu3g.19796$tN3.14799@newssvr27.news.prodigy.net...[color=darkred]
>>> "Ernie Sty" <fake_email@yahoo.com> wrote in message
>>> news:66qdnXStUv7v8tPZnZ2dnUVZ_vGdnZ2d@giganews.com...
>>>> Mechanic told me the oil pressure sending unit (this is the same as the
>>>> oil pressure sensor, right?) was leaking. I checked and yeah, it is
>>>> wet with oil but I did not see any drips on the garage floor.
>>>> Nevertheless this seems like something I could do myself but I'm having
>>>> trouble finding anything on it in my Haynes manual.
>>>>
>>>> How do I find answers to my questions about replacing this unit,
>>>> mainly, what torque setting do I use and is there anything unusual I
>>>> need to know about changing it? I already figured out I'd need to
>>>> drain the oil first and refill it after.
>>>
>>> You don't say what vehicle, but generally, no need to drain the oil.
>>>
>>> Just get a new sender, unscrew the old with a pair of pliers, wrap a
>>> couple of loops of teflon tape around the threads of the new sender, and
>>> screw it in as tight as you can by hand (no tools). Start the engine
>>> and check for leaks - if so, turn it in a quarter turn at a time until
>>> it stops.[/color]
>>
>>
>> Thanks! I forgot to mention it's a 1994 Geo Metro with the 3-cyl engine.
>> That's why it's an OT post. I believe you when you say I don't have to
>> drain the oil, but am curious as to how it can leak oil if it's above the
>> oil level? It's located on the back side, and there's no way the engine
>> could ever generate enough acceleration to slosh the oil back... I
>> suppose it could happen then I apply the brakes while backing down the
>> driveway...[/color]
>
> The oil pressure sender, as the name implies, senses oil pressure. When
> the engine is running, oil is pumped under pressure throughout the engine.
> In other words, it is leaking because of the pressure behind it, not
> because of the oil level.
> --
>
> Ray O
> (correct punctuation to reply)[/color]


So, when the engine is off and there's no pressure, I remove the sensor, and
no oil comes out the hole it was in, OK, that I've got.

But why, when I remove the sensor, doesn't the oil drain out of the hole it
was in by gravity the same way it would out of any other hole in the
crankcase? Is the sensor in some sort of oil passageway through which
pressurized oil flows in order to get to where it's being pumped, and when
the pump shuts off, the oil drains from that passageway back into the
crankcase, leaving the sensor above the oil level?

"Hachiroku" <Trueno@ae86.GTS> wrote in message
news:O2v3g.4951$cc.2161@trndny05...[color=blue]
>
> "Ernie Sty" <fake_email@yahoo.com> wrote in message
> news:66qdnXStUv7v8tPZnZ2dnUVZ_vGdnZ2d@giganews.com...[color=green]
>> Mechanic told me the oil pressure sending unit (this is the same as the
>> oil pressure sensor, right?) was leaking. I checked and yeah, it is wet
>> with oil but I did not see any drips on the garage floor. Nevertheless
>> this seems like something I could do myself but I'm having trouble
>> finding anything on it in my Haynes manual.
>>
>> How do I find answers to my questions about replacing this unit, mainly,
>> what torque setting do I use and is there anything unusual I need to know
>> about changing it? I already figured out I'd need to drain the oil first
>> and refill it after.
>>[/color]
>
> What kind of car is it? I have to replace the one in my Supra, the TSRM
> shows it at the front of the motor, but I'll be dammed if'n I can find it![/color]

Geo Metro with the 3-cyl. They may be sluggish but they sure are easy to
work on. When I look at the engine, sometimes I think that if I was ever
going to rebuild it, I'd just carry the engine into the house, wash it in
the sink, and work on it on the kitchen table. ;-)

"Ernie Sty" <fake_email@yahoo.com> wrote in message
news:V4OdnYxufYDcDtPZnZ2dnUVZ_s6dnZ2d@giganews.com...[color=blue]
>
> "Ray O" <rokigawa@tristarassociatesDOTcomn> wrote in message
> news:94321$444e802d$44a4a10d$23182@msgid.meganewsservers.com...[color=green]
>>
>> "Ernie Sty" <fake_email@yahoo.com> wrote in message
>> news:2KudnWxOs7gz59PZnZ2dnUVZ_sednZ2d@giganews.com...[color=darkred]
>>>
>>> "Mike Harris" <harrisremovethiswest@sbcglobal.net> wrote in message
>>> news:hGu3g.19796$tN3.14799@newssvr27.news.prodigy.net...
>>>> "Ernie Sty" <fake_email@yahoo.com> wrote in message
>>>> news:66qdnXStUv7v8tPZnZ2dnUVZ_vGdnZ2d@giganews.com...
>>>>> Mechanic told me the oil pressure sending unit (this is the same as
>>>>> the oil pressure sensor, right?) was leaking. I checked and yeah, it
>>>>> is wet with oil but I did not see any drips on the garage floor.
>>>>> Nevertheless this seems like something I could do myself but I'm
>>>>> having trouble finding anything on it in my Haynes manual.
>>>>>
>>>>> How do I find answers to my questions about replacing this unit,
>>>>> mainly, what torque setting do I use and is there anything unusual I
>>>>> need to know about changing it? I already figured out I'd need to
>>>>> drain the oil first and refill it after.
>>>>
>>>> You don't say what vehicle, but generally, no need to drain the oil.
>>>>
>>>> Just get a new sender, unscrew the old with a pair of pliers, wrap a
>>>> couple of loops of teflon tape around the threads of the new sender,
>>>> and screw it in as tight as you can by hand (no tools). Start the
>>>> engine and check for leaks - if so, turn it in a quarter turn at a time
>>>> until it stops.
>>>
>>>
>>> Thanks! I forgot to mention it's a 1994 Geo Metro with the 3-cyl
>>> engine. That's why it's an OT post. I believe you when you say I don't
>>> have to drain the oil, but am curious as to how it can leak oil if it's
>>> above the oil level? It's located on the back side, and there's no way
>>> the engine could ever generate enough acceleration to slosh the oil
>>> back... I suppose it could happen then I apply the brakes while backing
>>> down the driveway...[/color]
>>
>> The oil pressure sender, as the name implies, senses oil pressure. When
>> the engine is running, oil is pumped under pressure throughout the
>> engine. In other words, it is leaking because of the pressure behind it,
>> not because of the oil level.
>> --
>>
>> Ray O
>> (correct punctuation to reply)[/color]
>
>
> So, when the engine is off and there's no pressure, I remove the sensor,
> and no oil comes out the hole it was in, OK, that I've got.
>
> But why, when I remove the sensor, doesn't the oil drain out of the hole
> it was in by gravity the same way it would out of any other hole in the
> crankcase? Is the sensor in some sort of oil passageway through which
> pressurized oil flows in order to get to where it's being pumped, and when
> the pump shuts off, the oil drains from that passageway back into the
> crankcase, leaving the sensor above the oil level?[/color]

You have correctly answered your own question!
--

Ray O
(correct punctuation to reply)

On Tue, 25 Apr 2006 16:26:03 -0500, Ernie Sty wrote:
[color=blue]
>
> "Hachiroku" <Trueno@ae86.GTS> wrote in message
> news:O2v3g.4951$cc.2161@trndny05...[color=green]
>>
>> "Ernie Sty" <fake_email@yahoo.com> wrote in message
>> news:66qdnXStUv7v8tPZnZ2dnUVZ_vGdnZ2d@giganews.com...[color=darkred]
>>> Mechanic told me the oil pressure sending unit (this is the same as the
>>> oil pressure sensor, right?) was leaking. I checked and yeah, it is wet
>>> with oil but I did not see any drips on the garage floor. Nevertheless
>>> this seems like something I could do myself but I'm having trouble
>>> finding anything on it in my Haynes manual.
>>>
>>> How do I find answers to my questions about replacing this unit, mainly,
>>> what torque setting do I use and is there anything unusual I need to know
>>> about changing it? I already figured out I'd need to drain the oil first
>>> and refill it after.
>>>[/color]
>>
>> What kind of car is it? I have to replace the one in my Supra, the TSRM
>> shows it at the front of the motor, but I'll be dammed if'n I can find it![/color]
>
> Geo Metro with the 3-cyl. They may be sluggish but they sure are easy to
> work on. When I look at the engine, sometimes I think that if I was ever
> going to rebuild it, I'd just carry the engine into the house, wash it in
> the sink, and work on it on the kitchen table. ;-)[/color]


You could pretty much do that! I beleive the engine weighs about 90 pounds.

"Mike Harris" <harrisremovethiswest@sbcglobal.net> wrote:
[color=blue]
>"Ernie Sty" <fake_email@yahoo.com> wrote in message
>news:66qdnXStUv7v8tPZnZ2dnUVZ_vGdnZ2d@giganews.com...[color=green]
>> Mechanic told me the oil pressure sending unit (this is the same as the
>> oil pressure sensor, right?) was leaking. I checked and yeah, it is wet
>> with oil but I did not see any drips on the garage floor. Nevertheless
>> this seems like something I could do myself but I'm having trouble finding
>> anything on it in my Haynes manual.
>>
>> How do I find answers to my questions about replacing this unit, mainly,
>> what torque setting do I use and is there anything unusual I need to know
>> about changing it? I already figured out I'd need to drain the oil first
>> and refill it after.[/color]
>
>You don't say what vehicle, but generally, no need to drain the oil.
>
>Just get a new sender, unscrew the old with a pair of pliers, wrap a couple
>of loops of teflon tape around the threads of the new sender, and screw it
>in as tight as you can by hand (no tools). Start the engine and check for
>leaks - if so, turn it in a quarter turn at a time until it stops.
>[/color]

Or make it 'Newfie tight'...

--

-Gord.
(use gordon in email)

"Ray O" <rokigawa@tristarassociatesDOTcomn> wrote in message
news:928b4$444e98ae$44a4a10d$23737@msgid.meganewsservers.com...[color=blue]
>
> "Ernie Sty" <fake_email@yahoo.com> wrote in message
> news:V4OdnYxufYDcDtPZnZ2dnUVZ_s6dnZ2d@giganews.com...[color=green]
>>
>> "Ray O" <rokigawa@tristarassociatesDOTcomn> wrote in message
>> news:94321$444e802d$44a4a10d$23182@msgid.meganewsservers.com...[color=darkred]
>>>
>>> "Ernie Sty" <fake_email@yahoo.com> wrote in message
>>> news:2KudnWxOs7gz59PZnZ2dnUVZ_sednZ2d@giganews.com...
>>>>
>>>> "Mike Harris" <harrisremovethiswest@sbcglobal.net> wrote in message
>>>> news:hGu3g.19796$tN3.14799@newssvr27.news.prodigy.net...
>>>>> "Ernie Sty" <fake_email@yahoo.com> wrote in message
>>>>> news:66qdnXStUv7v8tPZnZ2dnUVZ_vGdnZ2d@giganews.com...
>>>>>> Mechanic told me the oil pressure sending unit (this is the same as
>>>>>> the oil pressure sensor, right?) was leaking. I checked and yeah, it
>>>>>> is wet with oil but I did not see any drips on the garage floor.
>>>>>> Nevertheless this seems like something I could do myself but I'm
>>>>>> having trouble finding anything on it in my Haynes manual.
>>>>>>
>>>>>> How do I find answers to my questions about replacing this unit,
>>>>>> mainly, what torque setting do I use and is there anything unusual I
>>>>>> need to know about changing it? I already figured out I'd need to
>>>>>> drain the oil first and refill it after.
>>>>>
>>>>> You don't say what vehicle, but generally, no need to drain the oil.
>>>>>
>>>>> Just get a new sender, unscrew the old with a pair of pliers, wrap a
>>>>> couple of loops of teflon tape around the threads of the new sender,
>>>>> and screw it in as tight as you can by hand (no tools). Start the
>>>>> engine and check for leaks - if so, turn it in a quarter turn at a
>>>>> time until it stops.
>>>>
>>>>
>>>> Thanks! I forgot to mention it's a 1994 Geo Metro with the 3-cyl
>>>> engine. That's why it's an OT post. I believe you when you say I don't
>>>> have to drain the oil, but am curious as to how it can leak oil if it's
>>>> above the oil level? It's located on the back side, and there's no way
>>>> the engine could ever generate enough acceleration to slosh the oil
>>>> back... I suppose it could happen then I apply the brakes while
>>>> backing down the driveway...
>>>
>>> The oil pressure sender, as the name implies, senses oil pressure. When
>>> the engine is running, oil is pumped under pressure throughout the
>>> engine. In other words, it is leaking because of the pressure behind it,
>>> not because of the oil level.
>>> --
>>>
>>> Ray O
>>> (correct punctuation to reply)[/color]
>>
>>
>> So, when the engine is off and there's no pressure, I remove the sensor,
>> and no oil comes out the hole it was in, OK, that I've got.
>>
>> But why, when I remove the sensor, doesn't the oil drain out of the hole
>> it was in by gravity the same way it would out of any other hole in the
>> crankcase? Is the sensor in some sort of oil passageway through which
>> pressurized oil flows in order to get to where it's being pumped, and
>> when the pump shuts off, the oil drains from that passageway back into
>> the crankcase, leaving the sensor above the oil level?[/color]
>
> You have correctly answered your own question!
> --
>
> Ray O
> (correct punctuation to reply)[/color]


I have amazed myself! ;-)

Thanks. :-)

"Gord Beaman" <gord@islandtelecom.com> wrote in message
news:smdt42tqa3nf4t4uknul68miq9jgslnouh@4ax.com...[color=blue]
> "Mike Harris" <harrisremovethiswest@sbcglobal.net> wrote:
>[color=green]
>>"Ernie Sty" <fake_email@yahoo.com> wrote in message
>>news:66qdnXStUv7v8tPZnZ2dnUVZ_vGdnZ2d@giganews.com...[color=darkred]
>>> Mechanic told me the oil pressure sending unit (this is the same as the
>>> oil pressure sensor, right?) was leaking. I checked and yeah, it is wet
>>> with oil but I did not see any drips on the garage floor. Nevertheless
>>> this seems like something I could do myself but I'm having trouble
>>> finding
>>> anything on it in my Haynes manual.
>>>
>>> How do I find answers to my questions about replacing this unit, mainly,
>>> what torque setting do I use and is there anything unusual I need to
>>> know
>>> about changing it? I already figured out I'd need to drain the oil
>>> first
>>> and refill it after.[/color]
>>
>>You don't say what vehicle, but generally, no need to drain the oil.
>>
>>Just get a new sender, unscrew the old with a pair of pliers, wrap a
>>couple
>>of loops of teflon tape around the threads of the new sender, and screw it
>>in as tight as you can by hand (no tools). Start the engine and check for
>>leaks - if so, turn it in a quarter turn at a time until it stops.
>>[/color]
>
> Or make it 'Newfie tight'...[/color]


Don't break the heavy-duty torque wrench on it then?

"Ernie Sty" <fake_email@yahoo.com> wrote in message
news:Jt2dnWF_WulaM9LZnZ2dnUVZ_uWdnZ2d@giganews.com...[color=blue]
>
> "<snipped>[/color]
[color=blue][color=green]
>> So, when the engine is off and there's no pressure, I remove the sensor,[color=darkred]
>>> and no oil comes out the hole it was in, OK, that I've got.
>>>
>>> But why, when I remove the sensor, doesn't the oil drain out of the hole
>>> it was in by gravity the same way it would out of any other hole in the
>>> crankcase? Is the sensor in some sort of oil passageway through which
>>> pressurized oil flows in order to get to where it's being pumped, and
>>> when the pump shuts off, the oil drains from that passageway back into
>>> the crankcase, leaving the sensor above the oil level?[/color]
>>
>> You have correctly answered your own question!
>> --
>>
>> Ray O
>> (correct punctuation to reply)[/color]
>
>
> I have amazed myself! ;-)
>
> Thanks. :-)[/color]

Amazing yourself is the best way to be amazed! You never have to worry
about what others are thinking.
--

Ray O
(correct punctuation to reply)