Google
Home » GMC » GMCnet » [GMCnet] Fluctuating Oil Gauge Readings
[GMCnet] Fluctuating Oil Gauge Readings [message #189620] Thu, 08 November 2012 11:55 Go to next message
enate98690  is currently offline enate98690
Messages: 23
Registered: January 2012
Junior Member
Hi,

Does anyone know why the oil gauge readings on the GM/Olds engines fluctuate with engine speed (i.e., lower pressure at lower RPM and vice versa)? I have seen this occur with other engines but also note that the reading on my 2006 Dodge Truck NEVER fluctuates.

I don't believe this is just an oil pressure sender unit issue. It would seem that it would be the way the engine is designed with Chrysler etc using a system that just relieves excess pressure (to get the consistent reading) with GM using a design that just pumps the oil directly to the engine based on engine speed.

Does anyone have any information on this issue?
Thanks!
Keith Lee
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189635 is a reply to message #189620 ] Thu, 08 November 2012 14:10 Go to previous messageGo to next message
James Hupy  is currently offline James Hupy
Messages: 2526
Registered: May 2010
Senior Member
Keith, It is a matter of the engine design. Modern engines have closer
tolerances and are designed to have higher oil pressure even at idle. The
pumps produce more pressure even at idle then the Oldsmobile does.
Therefore the bypass circuit is in operation even at low engine speed with
the result that there is almost no fluctuation on the guage. Olds engines
for the most part bypass only above 35psi on the stock pump, and when the
engine is running at idle, the camshaft driven oil pump which turns at 1/2
engine rpm does not produce much pressure, which is a result of restriction
to flow. They can be modified to produce higher pressure as well as
increased volume, BUT the oil returns for the heads are not sized to return
a large volume of oil, so the rocker arm covers will retain a good deal of
oil at high engine speed like climbing long grades with the result of oil
starvation to the crank and cam bearings. Not a particularly good thing for
engine durability. They can be enlarged but such work is by hand by experts
and not inexpensive.
Jim Hupy
Salem, OR
78 GMC Royale 403

On Thu, Nov 8, 2012 at 9:55 AM, <enate98690@mypacks.net> wrote:

> Hi,
>
> Does anyone know why the oil gauge readings on the GM/Olds engines
> fluctuate with engine speed (i.e., lower pressure at lower RPM and vice
> versa)? I have seen this occur with other engines but also note that the
> reading on my 2006 Dodge Truck NEVER fluctuates.
>
> I don't believe this is just an oil pressure sender unit issue. It would
> seem that it would be the way the engine is designed with Chrysler etc
> using a system that just relieves excess pressure (to get the consistent
> reading) with GM using a design that just pumps the oil directly to the
> engine based on engine speed.
>
> Does anyone have any information on this issue?
> Thanks!
> Keith Lee
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189648 is a reply to message #189620 ] Thu, 08 November 2012 17:14 Go to previous messageGo to next message
JohnL455  is currently offline JohnL455
Messages: 1711
Registered: October 2006
Location: CHICAGO
Senior Member
Think of it as a poor man's tach... or a poor man's temp gauge ( lower when hotter) Ha. Actually all cars I have ever had respond this way and it's normal. Us older guys think of the new fixed position gauge as odd.


John Lebetski
Chicago, IL
77 Eleganza II
Source America First
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189658 is a reply to message #189620 ] Thu, 08 November 2012 17:55 Go to previous messageGo to next message
Ken Henderson  is currently offline Ken Henderson
Messages: 4950
Registered: March 2004
Location: Americus, GA
Senior Member
Keith,

I agree with all the comments about how our oil pressure gauges work. As
another point of interest: I've learned that some "modern" vehicles (I
don't have an example off hand) have "gauges" which are connected to
SWITCHES! In other words, the needles are really nothing but
non-illuminating idiot lights!

If a dealer sold me a vehicle with one of those, I'm sure I'd return it and
never buy another of that brand since I consider that such a deceptive
practice.

Ken H.

On Thu, Nov 8, 2012 at 12:55 PM, wrote:
>
> Does anyone know why the oil gauge readings on the GM/Olds engines
> fluctuate with engine speed (i.e., lower pressure at lower RPM and vice
> versa)? I have seen this occur with other engines but also note that the
> reading on my 2006 Dodge Truck NEVER fluctuates.
> ...
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist


Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189698 is a reply to message #189620 ] Fri, 09 November 2012 00:36 Go to previous messageGo to next message
John Heslinga  is currently offline John Heslinga
Messages: 287
Registered: February 2011
Location: Edmonton, Alberta, Canada
Senior Member
Hi Keith:

An interesting thing about the OLDS engine is that the oil pressure sending unit is tapped at the low pressure end of oil Galleries, rather than tapped at the high pressure side of the Galleries. (Farthest away from the oil pump.) This means that you will SEE more pressure fluctuations with temperature. (As others have said fluctuations with speed and temperature are normal)

In my experience this is actually quite uncommon. Most of the engines I've worked with have their oil pressure sending units tapped on the downstream side of the oil filter where the oil enters the oil galleries. (Chevy Ford, and Chrysler V8s)

The Olds oil circuit is from the pump to cooler to filter to oil galleries (Left, Right, Main, and Cam Bearings)then the oil pressure tap. This means that the oil pressure your reading, is actually after all of the volume "leaks" of the bearings, lifters, valve train and the pressure losses of the oil passages themselves. When the engine warms up, clearances open up a bit and increases the "leaks", hence the significant and visible pressure drop at the end of the line.

Here is a flow diagram from the manual.
http://www.gmcmhphotos.com/photos/discussion-photos/p46304-oil-passages.html


When the oil pressure tap is at the oil filter these pressure drops are not as evident because the oil pump actually bypasses a certain amount of oil as the pressure relief valve opens and dumps the oil back to the oil pan. (Less so when the oil warms up and only to the capacity of the oil pump) As the needs of the engine increase, the oil pump will dump less and will make up the difference and you will see less of the fluctuations on the pressure gauge. You will find that the needles of these engines will not move as much. (More Stable) Most gauges in many vehicles are also designed to respond slower to eliminate the pulsing that you might be seeing and to simply give an indication of the oil pressure. ( The same as the Gas gauge is slowed down significantly so it does not annoyingly indicate the sloshing of the fuel in the tank. ) The reality is, very few people want to know the intimate details of the engine and indications are telling enough. The oil pressure trends over the last 3 to 10 seconds is usually plenty enough information for most people.

A hot engine that idles at 500 to 700 RMP results in the oil pump only turning at 250 to 350 RPM . The pump does not move a lot of oil and, a lot of oil leaks past the clearances. The pressure on the end of a gallery such as our 455 can actually be be quite low and still be sufficient for the needs of the engine. Especially if it increases when the engine warms up. If the other engines show that low a pressure at the pump there may actually be nothing at the end of the gallery

When I rebuilt my engine, I put in a Melling High Volume Oil pump. I set up an pressure gauge and primed the engine with this drive and a hand drill. It really loaded the drill and the oil pump dumped oil flow at 50 PSI When the engine gets warm pressure does drop a bit at idle but stays very even above idle.

Gauge set up
http://www.gmcmhphotos.com/photos/discussion-photos/p46316-pressure-guage-setup.html

Adaptor for priming
http://www.gmcmhphotos.com/photos/discussion-photos/p46310-pump-prime-drive.html

Priming with drill
http://www.gmcmhphotos.com/photos/discussion-photos/p46313-driving-oil-pump.html

Resulting Pressure
http://www.gmcmhphotos.com/photos/discussion-photos/p46307-oil-pump-dumps.html

Best Regards


John and Cathie Heslinga 1974 Canyonlands 260 455, Manny tranny and 1 ton, 3:73 LS, TC4W "Too Cool For Words" Retirement Projects Galore Edmonton, Alberta
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189700 is a reply to message #189698 ] Fri, 09 November 2012 05:25 Go to previous messageGo to next message
USAussie  is currently offline USAussie
Messages: 11483
Registered: July 2007
Location: Sydney, Australia
Senior Member
John,

I reckon the engineers at GM were smarter than the engineers at the other car companies! By locating the oil pressure tap at the end
of the oil feed you know that the pressure gets higher as you head "upstream."

Regards,
Rob M.

-----Original Message-----
From: John Heslinga

Hi Keith:

An interesting thing about the OLDS engine is that the oil pressure sending unit is tapped at the low pressure end of oil Galleries,
rather than tapped at the high pressure side of the Galleries. (Farthest away from the oil pump.) This means that you will SEE
more pressure fluctuations with temperature. (As others have said fluctuations with speed and temperature are normal)

In my experience this is actually quite uncommon. Most of the engines I've worked with have their oil pressure sending units tapped
on the downstream side of the oil filter where the oil enters the oil galleries. (Chevy Ford, and Chrysler V8s)

John

_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist


Regards,
Rob M.
(USAussie)
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189715 is a reply to message #189700 ] Fri, 09 November 2012 08:24 Go to previous messageGo to next message
Matt Colie  is currently offline Matt Colie
Messages: 4109
Registered: March 2007
Location: S.E. Michigan
Senior Member
Robert Mueller wrote on Fri, 09 November 2012 06:25

John,

I reckon the engineers at GM were smarter than the engineers at the other car companies! By locating the oil pressure tap at the end of the oil feed you know that the pressure gets higher as you head "upstream."

Regards,
Rob M.

Rob,

Not GM as a whole, but those in one group could be counted on to hold out. While Olds in Lansing was still independent, they were know as being the kind of wild and quality crazy guys....

They got away with lots of things that were antithetical to the rest of GM. They drove the bean counters crazy by refusing to buy the cheapest rings, bearings and seals. They got blocks and heads cast with a nickle content that was "way too high".

This is why Oldsmobile died shortly after they were forced by GM to use the Chevy SB in most of their line. Buyers stayed away in droves as soon as that was discovered.

Matt


Matt & Mary Colie - Members GMCMI, GMCES
Getting Ready for Hamilton
'73 Glacier 23 With 4 Rear Brakes that pull as they should
SE Michigan - Twixt A2 and Detroit
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189745 is a reply to message #189715 ] Fri, 09 November 2012 16:05 Go to previous messageGo to next message
USAussie  is currently offline USAussie
Messages: 11483
Registered: July 2007
Location: Sydney, Australia
Senior Member
Matt,

I just looked at the oil flow schematic in my 1972 Cadillac shop manual and guess what; the oil pressure switch is in a similar
location flow wise. Guess the engineers at Caddy were cut from the same cloth (probably even more expensive cloth at that)! I wonder
if they had to do battle with the bean counters as well?

Regards,
Rob M.

-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org [mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Matt Colie


Rob,

Not GM as a whole, but those in one group could be counted on to hold out. While Olds in Lansing was still independent, they were
know as being the kind of wild and quality crazy guys....

They got away with lots of things that were antithetical to the rest of GM. They drove the bean counters crazy by refusing to buy
the cheapest rings, bearings and seals. They got blocks and heads cast with a nickle content that was "way too high".

This is why Oldsmobile died shortly after they were forced by GM to use the Chevy SB in most of their line. Buyers stayed away in
droves as soon as that was discovered.

Matt

_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist


Regards,
Rob M.
(USAussie)
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189752 is a reply to message #189745 ] Fri, 09 November 2012 17:48 Go to previous messageGo to next message
Matt Colie  is currently offline Matt Colie
Messages: 4109
Registered: March 2007
Location: S.E. Michigan
Senior Member
Robert Mueller wrote on Fri, 09 November 2012 17:05

Matt,

I just looked at the oil flow schematic in my 1972 Cadillac shop manual and guess what; the oil pressure switch is in a similar
location flow wise. Guess the engineers at Caddy were cut from the same cloth (probably even more expensive cloth at that)! I wonder
if they had to do battle with the bean counters as well?

Regards,
Rob M.

Oh Rob,,

I know they did... Caddy also had the good castings. I was some small part of it. (Regularly rewriting reports to clearly demonstrate some point or other for the client.) Part of what you might not know is that for very many years GM was organized as BOC and CPC. (Some said these were abbreviations for Big Opulent Cars and Cheap Practical Cars, but that was never confirmed.) The bean counters were always on Chevy to reduce cost. This had some humorous side effects that are still industry legend.

Matt


Matt & Mary Colie - Members GMCMI, GMCES
Getting Ready for Hamilton
'73 Glacier 23 With 4 Rear Brakes that pull as they should
SE Michigan - Twixt A2 and Detroit
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189757 is a reply to message #189620 ] Fri, 09 November 2012 18:30 Go to previous messageGo to next message
kingd  is currently offline kingd
Messages: 369
Registered: June 2004
Senior Member
My 440 Dodge engine has the oil pump at the front of the engine, and the oil pressure sending hole is at the back of the engine. Distributor at the front.
I guess some of the "Chrysler" engine designers/engineers went to the same school as the Caddy and Olds people.


DAVE KING lurker, wannabe Toronto, Ontario, Canada
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189770 is a reply to message #189620 ] Fri, 09 November 2012 20:36 Go to previous messageGo to next message
bobby5832708  is currently offline bobby5832708
Messages: 118
Registered: November 2006
Location: Winter Springs FL
Senior Member
Ken,

In reference to:

"I agree with all the comments about how our oil pressure gauges work. As
another point of interest: I've learned that some "modern" vehicles (I
don't have an example off hand) have "gauges" which are connected to
SWITCHES! In other words, the needles are really nothing but
non-illuminating idiot lights!"


My 2005 Crown Vic has an oil pressure gauge that works this way, it's either all the way down or exactly half way. In the Ford service manual it explains the operation of the sender and this is the way it is supposed to work, it's a 'yes/no', not a 'how much'.

I don't really see anything wrong with this setup, I personally think people get too obsessed about the oil pressure and coolant temp readings. Example: Years ago a good friend used to go nuts when his engine would get to 200 when idling in a traffic jam (typical New Jersey traffic) and would shut the air con off, go to neutral, rev to get the fan spinning faster, etc. When we drove my car I really didn't care what the coolant temp was as long as it was below the 'hot' mark and I would leave the a/c on so we were comfortable. Sure, the engine was hotter than normal but if we weren't losing coolant and the engine was still running properly I could care less if the temp was a bit warm. It will cool down to normal once we get moving again. I don't really think it makes a difference if the coolant is 180 or 210 degrees, as long as the engine is running well and not losing coolant I don't worry about it.

Same thing with oil pressure gauges. If the engine makes strange noises and the oil light comes on then you might want to check it out, otherwise it will run fine whether it has 30 psi or 50 psi and probably will run fine for many miles. I've had some really 'used' cars in my life and have never had an engine come apart. I've had cars where the oil light would sometimes flicker at idle (an old Mopar 383 comes to mind) and still beat the crap out of them and they never came apart (I used to love $100 cars in my teens and early 20's). I always use a good quality name-brand oil of the weight that the car manufacturer recommends and have never had engine issues.

Maybe the GMC designers should've put in idiot lights, that would solve the gauge-obsession some of us have. Sometimes "driving in suspense" is a good thing. Just drive until smoke or steam comes out and then fix it! I will probably change my mind when I have an engine eventually fail on me but until then I plan to just drive on and not worry about trivial things.

Just my opinion.



Bob Heller
1974 X-Canyonlands 26ft
Winter Springs FL
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189773 is a reply to message #189770 ] Fri, 09 November 2012 21:35 Go to previous messageGo to next message
USAussie  is currently offline USAussie
Messages: 11483
Registered: July 2007
Location: Sydney, Australia
Senior Member
Bob,

I understand your comments and agree to a point.

Gauges allow you to monitor what's going on over time. You're buddy that got wrapped around the axle when the temp went up was
paranoid which is understandable since he's from Joisey. UNLESS he had experience that it would continue to rise until it was a
problem.

I have a Digi-Panel on Double Trouble that keeps an eye on critical engine parameters. Once in awhile I'll glance down at the gages
to see what's going on and through experience I know what the readings are. If over time I notice a change I know something's going
on. With an idiot light you have to wait until it happens. Frankly I don't want to wait until steam or smoke comes out as that could
cost more than addressing a trivial thing.

For example if you know that your charging system puts out 14 volts and it drops to 13.5 then 13 then 12.5 you know something is
happening and can do something about it.

If your engine puts out 50 psi oil pressure at 60 mph and it drops to 45, then 40 then 35 you know something is going on and take
action.

Same scenario goes for other parameters monitored.

Regards,
Rob M.

PS - I'm from Hoboken

-----Original Message-----
From: Bob Heller

Ken,

In reference to:

"I agree with all the comments about how our oil pressure gauges work. As
another point of interest: I've learned that some "modern" vehicles (I
don't have an example off hand) have "gauges" which are connected to
SWITCHES! In other words, the needles are really nothing but
non-illuminating idiot lights!"

My 2005 Crown Vic has an oil pressure gauge that works this way, it's either all the way down or exactly half way. In the Ford
service manual it explains the operation of the sender and this is the way it is supposed to work, it's a 'yes/no', not a 'how
much'.

I don't really see anything wrong with this setup, I personally think people get too obsessed about the oil pressure and coolant
temp readings. Example: Years ago a good friend used to go nuts when his engine would get to 200 when idling in a traffic jam
(typical New Jersey traffic) and would shut the air con off, go to neutral, rev to get the fan spinning faster, etc. When we drove
my car I really didn't care what the coolant temp was as long as it was below the 'hot' mark and I would leave the a/c on so we were
comfortable. Sure, the engine was hotter than normal but if we weren't losing coolant and the engine was still running properly I
could care less if the temp was a bit warm. It will cool down to normal once we get moving again. I don't really think it makes a
difference if the coolant is 180 or 210 degrees, as long as the engine is running well and not losing coolant I don't worry about
it.

Same thing with oil pressure gauges. If the engine makes strange noises and the oil light comes on then you might want to check it
out, otherwise it will run fine whether it has 30 psi or 50 psi and probably will run fine for many miles. I've had some really
'used' cars in my life and have never had an engine come apart. I've had cars where the oil light would sometimes flicker at idle
(an old Mopar 383 comes to mind) and still beat the crap out of them and they never came apart (I used to love $100 cars in my teens
and early 20's). I always use a good quality name-brand oil of the weight that the car manufacturer recommends and have never had
engine issues.

Maybe the GMC designers should've put in idiot lights, that would solve the gauge-obsession some of us have. Sometimes "driving in
suspense" is a good thing. Just drive until smoke or steam comes out and then fix it! I will probably change my mind when I have an
engine eventually fail on me but until then I plan to just drive on and not worry about trivial things.

Just my opinion.
--
Bob

_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist


Regards,
Rob M.
(USAussie)
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189778 is a reply to message #189620 ] Sat, 10 November 2012 00:49 Go to previous messageGo to next message
Craig Lechowicz  is currently offline Craig Lechowicz
Messages: 506
Registered: October 2006
Location: Waterford, MI
Senior Member
I can't recall who the quote was from, but thinking it was maybe from Richard Petty. "I don't know why they put all these gauges in these race cars, I'm just going to drive it till it blows up anyways"


Craig Lechowicz
'77 Kingsley, Waterford, MI
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189784 is a reply to message #189757 ] Sat, 10 November 2012 07:40 Go to previous messageGo to next message
Johnny Bridges  is currently offline Johnny Bridges
Messages: 3528
Registered: May 2011
Location: Braselton ga
Senior Member
On the B and RB engines, that's also about the easiest place to hit an oil gallery close to the block surface... and if you use a mechanical guage, the pipe is a lot shorter.  :)
 
--johnny
'76 23' transmode norris
'76 palm beach
 

From: Dave King <kingd@sympatico.ca>
To: gmclist@temp.gmcnet.org
Sent: Friday, November 9, 2012 7:30 PM
Subject: Re: [GMCnet] Fluctuating Oil Gauge Readings



My 440 Dodge engine has the oil pump at the front of the engine, and the oil pressure sending hole is at the back of the engine. Distributor at the front.
I guess some of the "Chrysler" engine designers/engineers went to the same school as the Caddy and Olds people.
--
DAVE KING
lurker, wannabe
Toronto, Ontario, Canada
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist


"Sometimes I wonder what tomorrow's gonna bring when I think about my dirty life and times" --Warren Zevon
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189786 is a reply to message #189770 ] Sat, 10 November 2012 07:50 Go to previous messageGo to next message
Johnny Bridges  is currently offline Johnny Bridges
Messages: 3528
Registered: May 2011
Location: Braselton ga
Senior Member
Actually, if I had the Furd in that configuration, I'd replace the 'guage' with a light.  I'll notice a light coming on, while a dead pointer may languish for a bit before it's seen.  When I fire my coach up after i's been sitting, I like to see the oil go waaay up and hear the fan racket.  Tells me nothing essential has fallen off in the lastr few weeks and the fan clutch still has fluid in it.  I like to see the ammeters run over top the charge side and then ease back, too.   
 
--johnny
'76 23' transmode norris
'76 palm beach 

From: Bob Heller <rheller@cfl.rr.com>
To: gmclist@temp.gmcnet.org
Sent: Friday, November 9, 2012 9:36 PM
Subject: Re: [GMCnet] Fluctuating Oil Gauge Readings



Ken,

In reference to:

"I agree with all the comments about how our oil pressure gauges work. As
another point of interest: I've learned that some "modern" vehicles (I
don't have an example off hand) have "gauges" which are connected to
SWITCHES! In other words, the needles are really nothing but
non-illuminating idiot lights!"


My 2005 Crown Vic has an oil pressure gauge that works this way, it's either all the way down or exactly half way. In the Ford service manual it explains the operation of the sender and this is the way it is supposed to work, it's a 'yes/no', not a 'how much'.

I don't really see anything wrong with this setup, I personally think people get too obsessed about the oil pressure and coolant temp readings. Example: Years ago a good friend used to go nuts when his engine would get to 200 when idling in a traffic jam (typical New Jersey traffic) and would shut the air con off, go to neutral, rev to get the fan spinning faster, etc. When we drove my car I really didn't care what the coolant temp was as long as it was below the 'hot' mark and I would leave the a/c on so we were comfortable. Sure, the engine was hotter than normal but if we weren't losing coolant and the engine was still running properly I could care less if the temp was a bit warm. It will cool down to normal once we get moving again. I don't really think it makes a difference if the coolant is 180 or 210 degrees, as long as the engine is running well and not losing coolant I don't worry about it.

Same thing with oil pressure gauges. If the engine makes strange noises and the oil light comes on then you might want to check it out, otherwise it will run fine whether it has 30 psi or 50 psi and probably will run fine for many miles. I've had some really 'used' cars in my life and have never had an engine come apart. I've had cars where the oil light would sometimes flicker at idle (an old Mopar 383 comes to mind) and still beat the crap out of them and they never came apart (I used to love $100 cars in my teens and early 20's). I always use a good quality name-brand oil of the weight that the car manufacturer recommends and have never had engine issues.

Maybe the GMC designers should've put in idiot lights, that would solve the gauge-obsession some of us have. Sometimes "driving in suspense" is a good thing. Just drive until smoke or steam comes out and then fix it! I will probably change my mind when I have an engine eventually fail on me but until then I plan to just drive on and not worry about trivial things.

Just my opinion.



--
Bob Heller
1974 X-Canyonlands 26ft
Winter Springs FL
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist


"Sometimes I wonder what tomorrow's gonna bring when I think about my dirty life and times" --Warren Zevon
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189791 is a reply to message #189620 ] Sat, 10 November 2012 08:25 Go to previous messageGo to next message
g.winger  is currently offline g.winger
Messages: 745
Registered: February 2008
Location: Warrenton,Missouri
Senior Member
I think I can clear this up as to why and how. Warrenty!! Years ago customers were bringing in trucks with low OP complants. 75mph,,,headwind,,105 degrees,,AC,,uphill towing 10,000lbs. Get off the hiway and the gage would hit the peg and bounce. Now remember,,10lbs per 1k rpm,right. So 650 to 700 idle is 7psi. Now you no longer have a OP gage. Its a idiot needle(in place of a light) If its more than 6-8psi,,,,strait up and down. Your gas gage is programed also. It does not refect a true reading. It's programed to make you "think" your vehicle gets good fuel economy. Thats why your OP gage chages so much. I put an Oil Temp gage on the Caddy in the extra port on the dual remote. Was stunned at how hot it was. over 300. But its been a while,,,,still no dash,,,,,PL
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #189853 is a reply to message #189773 ] Sat, 10 November 2012 22:11 Go to previous messageGo to next message
Jim Galbavy  is currently offline Jim Galbavy
Messages: 821
Registered: August 2007
Senior Member
Rob and Bob, I agree with you (some what). I have installed some gauges but didn't go over the top. After all I have to drive and read the gauges (I don't have a co-pilot or flight engineer to do it for me). Just enough to tool on down the road and have a half way idea what is going on.

Just another x-Jersey boy.

jim galbavy
'73 x-CL ANNIE
Lake Mary, Fl
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #190444 is a reply to message #189770 ] Thu, 15 November 2012 22:15 Go to previous messageGo to next message
midlf  is currently offline midlf
Messages: 1429
Registered: July 2007
Location: SE Wisc. (Palmyra)
Senior Member
bobby5832708 wrote on Fri, 09 November 2012 20:36


My 2005 Crown Vic has an oil pressure gauge that works this way, it's either all the way down or exactly half way. In the Ford service manual it explains the operation of the sender and this is the way it is supposed to work, it's a 'yes/no', not a 'how much'.



'93 F-250 is the same. Ford has been doing this for some time. Now I gotta go check the shop manual for the '05 Merc GM and see what it does.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: [GMCnet] Fluctuating Oil Gauge Readings [message #190451 is a reply to message #190444 ] Fri, 16 November 2012 06:25 Go to previous message
Ken Henderson  is currently offline Ken Henderson
Messages: 4950
Registered: March 2004
Location: Americus, GA
Senior Member
My first new car was a '59 Ford Galaxy. I guess we now know why it was my
last Ford. :-)

Ken H.

bobby5832708 wrote on Fri, 09 November 2012 20:36
> > My 2005 Crown Vic has an oil pressure gauge that works this way, it's
> either all the way down or exactly half way. In the Ford service manual it
> explains the operation of the sender and this is the way it is supposed to
> work, it's a 'yes/no', not a 'how much'.
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist


Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Previous Topic:This GMC would be fun
Next Topic:78 Royale. Edinburg TX. $14.5k
Goto Forum:
  


Current Time: Sat Apr 19 12:38:55 CDT 2014

Total time taken to generate the page: 0.14824 seconds
.:: Contact :: Home ::.

Powered by: FUDforum 2.7.7RC2.
Copyright ©2001-2007 FUD Forum Bulletin Board Software