[DeTomaso] Oil Pressure Gauge
Tomas Gunnarsson
guson at home.se
Thu Sep 1 02:46:33 EDT 2016
I'd think that a light switch is closed when engine is off and open when
engine is up and running.
Tomas
<-----Ursprungligt Meddelande----->
From: Joseph F. Byrd, Jr. [byrdjf at embarqmail.com]
Sent: 1/9/2016 4:36:10 AM
To: detomaso at server.detomasolist.com
Subject: Re: [DeTomaso] Oil Pressure Gauge
Just saying....When I google NAPA OP6091, I get a SWITCH.
You could use a DMM and see if not running you have "open" and once
cranked
"closed". A sender would have about 70 ohms not running and approaching
0
running.
I would still want a mechanical gauge locally. ( I like Marshell's for
automotive)
Joe/NC
-----Original Message-----
From: DeTomaso [mailto:detomaso-bounces at server.detomasolist.com] On
Behalf
Of Mike Drew via DeTomaso
Sent: Wednesday, August 31, 2016 20:37 PM
To: mbefthomas at comcast.net; detomaso at server.detomasolist.com
Subject: Re: [DeTomaso] Oil Pressure Gauge
In a message dated 8/31/16 17 26 15, mbefthomas at comcast.net writes:
> I'm trying to figure out why I'm getting a pegged reading on my oil
> pressure gauge. It will show normal pressure as the car starts, but
> soon after pegs to the right and stays there. Everything runs fine
> otherwise. I've swapped out the pressure sender, NAPA OP6091, and
> it's still pegging, so I'm suspecting the gauge. Anything else I
> could check?
>
>>>Calling Bill Taylor! That is, assuming it's an electrical. You can't
make that assumption though.
I *think* I may have stumbled across something. Doing some primitive
Google research, I confirmed what I thought I knew, which is that the
oil
pressure gauge works by taking 12V power in, which runs across the
gauge,
then out
to the sender unit, which is a variable ground. The reading given by the
gauge depends on the resistance of the sensor unit; this in turn is
determined by the engine's oil pressure.
Extremely high readings after a cold start, if they are accurate, mean
the
pressure relief valve near the pump and filter has probably stuck. The
engine should be switched off or the oil filter could burst.
I have a mechanical oil pressure gauge which threads into the hole
normally
occupied by the electric sender. It is used to 'sanity check' the
readings on the gauge. It's the first troubleshooting tool; if the
mechanical
gauge reads high, you have an engine (or at least oil filter) problem.
If
it
reads normally, you have an electrical problem.
I could mail it to you tomorrow and you would have it by the weekend?
Let
me know if you would like to try it out.
Mike
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-------------- next part --------------
I'd think that a light switch is closed when engine is off and open
when engine is up and running.
Tomas
<-----Ursprungligt Meddelande----->
From: Joseph F. Byrd, Jr. [byrdjf at embarqmail.com]
Sent: 1/9/2016 4:36:10 AM
To: detomaso at server.detomasolist.com
Subject: Re: [DeTomaso] Oil Pressure Gauge
Just saying....When I google NAPA OP6091, I get a SWITCH.
You could use a DMM and see if not running you have "open" and once
cranked
"closed". A sender would have about 70 ohms not running and approaching
0
running.
I would still want a mechanical gauge locally. ( I like Marshell's for
automotive)
Joe/NC
-----Original Message-----
From: DeTomaso [mailto:detomaso-bounces at server.detomasolist.com] On
Behalf
Of Mike Drew via DeTomaso
Sent: Wednesday, August 31, 2016 20:37 PM
To: mbefthomas at comcast.net; detomaso at server.detomasolist.com
Subject: Re: [DeTomaso] Oil Pressure Gauge
In a message dated 8/31/16 17 26 15, mbefthomas at comcast.net writes:
> I'm trying to figure out why I'm getting a pegged reading on my oil
> pressure gauge. It will show normal pressure as the car starts, but
> soon after pegs to the right and stays there. Everything runs fine
> otherwise. I've swapped out the pressure sender, NAPA OP6091, and
> it's still pegging, so I'm suspecting the gauge. Anything else I
> could check?
>
>>>Calling Bill Taylor! That is, assuming it's an electrical. You can't
make that assumption though.
I *think* I may have stumbled across something. Doing some primitive
Google research, I confirmed what I thought I knew, which is that the
oil
pressure gauge works by taking 12V power in, which runs across the
gauge,
then out
to the sender unit, which is a variable ground. The reading given by
the
gauge depends on the resistance of the sensor unit; this in turn is
determined by the engine's oil pressure.
Extremely high readings after a cold start, if they are accurate, mean
the
pressure relief valve near the pump and filter has probably stuck. The
engine should be switched off or the oil filter could burst.
I have a mechanical oil pressure gauge which threads into the hole
normally
occupied by the electric sender. It is used to 'sanity check' the
readings on the gauge. It's the first troubleshooting tool; if the
mechanical
gauge reads high, you have an engine (or at least oil filter) problem.
If
it
reads normally, you have an electrical problem.
I could mail it to you tomorrow and you would have it by the weekend?
Let
me know if you would like to try it out.
Mike
_______________________________________________
Detomaso Email List is not managed by POCA
Posted emails must not exceed 1.5 Megabytes
DeTomaso mailing list
DeTomaso at server.detomasolist.com
http://server.detomasolist.com/mailman/listinfo/detomaso
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use the links above.
Members who post to this list grant license to the list to forward any
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list. They also grant the list owner permission to maintain an archive
or approve the archiving of list messages.
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