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#1 |
1972 Shorty Owner
Join Date: Feb 2007
Location: Stationed in Cali , born and raised in PHX Arizona.
Posts: 796
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Oil pressure
I already asked the same question in another thread but i wanted to be more specific this time with pics.
Ok in the first pic you can see what the gauge is at when i am at idle just below 1k rpm. The second pic is when i am driving at about 20-30 mph at or around 1200-1400 rpm. Should i be worried? The motor sounds fine and performs fine.
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1972 Chevy Shorty C-10- Project In Work http://67-72chevytrucks.com/gallery/...ATT1721941.jpg- New Project |
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#2 |
Senior Member
Join Date: Feb 2005
Location: Maynardville, Tn
Posts: 3,030
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Re: Oil pressure
I wouldn't be if the guage is correct. Most likely a high presure pump.
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SEMA Network- Protect our Hobby! 71 C30 in pieces, starting to come together. Click here for A Place For Tennessee Truck Enthusiest To Meet |
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#3 |
Registered User
Join Date: Sep 2006
Location: League City, Texas
Posts: 732
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Re: Oil pressure
Are these readings with the engine oil at full operating temperature or hot?
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#4 |
Senior Member
![]() Join Date: Dec 2006
Location: Studio City, Calif.
Posts: 2,873
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Re: Oil pressure
Isn't there a relief valve on these oil pumps to relieve pressure over a certain amount at start-up? In any case,I would try another oil gauge.
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'69 GMC C2500 Custom Camper, 8 1/2' bed, New GM 350, NP 435 Close Ratio 4spd. Trans., 3.73 Dana-60 open.Camper and Trailer wiring, PS, PB, AC, tach , three gas tanks, stereo speakers, 2nd owner, Work-Truck supreme. |
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#5 |
1972 Shorty Owner
Join Date: Feb 2007
Location: Stationed in Cali , born and raised in PHX Arizona.
Posts: 796
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Re: Oil pressure
I wouldnt say full operating temp ... it was running for about 15 mins.
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1972 Chevy Shorty C-10- Project In Work http://67-72chevytrucks.com/gallery/...ATT1721941.jpg- New Project |
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#6 |
Registered User
Join Date: Aug 2006
Location: Bakersfield,CA
Posts: 7,893
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Re: Oil pressure
what weight oil are you running??
i run 20-50 and my gauge is in the middle at idle and 3/4 while driving at full temp when i first start her up cold it sits at the 3/4 at idle
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-steven Alte Seele S.S. "Allison" '72 C/10 LWB 350SB/TH350 - DD PITBULL IS NOT A CRIME |
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#7 |
Sierra Grande Club
Join Date: Jan 2007
Location: New Mexico USA
Posts: 2,433
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Re: Oil pressure
I wanted to start this in a separate thread, but I’ll ask here as it might help.
I read that the oil pressure sending unit is near the oil filter. I’m not sure what the oil path is on these, but my thinking is you need to read the pressure at the end of the line. So if you have blockage somewhere you won’t read high and think you are fine, also if your pump is weak, you will show less pressure. Is the factory sending location in the beginning or at the end? LMK s/t
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1971 GMC Sierra Grande, 1/2 ton short wide, original 4 bolt 010 020 block & heads. (matching #'s). 383 stroker, SMI q jet 750 cfm, Lunati Voodoo 60102 cam, Scorpion roller rockers, Spin Tech pro street mufflers with X pipe. ![]() |
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#8 |
State of Confusion!
![]() ![]() Join Date: Jul 2002
Location: Gulfport, MS USA
Posts: 46,924
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Re: Oil pressure
These gauges are not that accurate, even when new. I suspect the gauge or sensor is the culprit. Cheaps and best way is to install an after market gauge and see what readings it provides. You can put a T on your mechanical pickup and have both gauges running for a comparison.
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Bill 1970 Chevy Custom/10 LWB Fleetside 2010 Toyota Tacoma PreRunner SR5 Double Cab - DD Member of Louisiana Classic Truck Club (LCTC) Bill's Gallery Life isn't tied with a bow, but it's still a gift. Live simply. Love generously. Care deeply. Speak kindly. Leave the rest to God! |
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#9 |
Registered User
Join Date: Apr 2006
Location: MinneSNOWta
Posts: 1,381
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Re: Oil pressure
These were mechanical gauges, and with any mechanical anything it can wear out over time.
the oil line leading to the gauge should connect at the top of the block (rear deck drivers side) directly behind the intake manifold. Personally i would get a cheapo mechanical gauge (around 10 bucks or less), and check the pressure. directly off block (disconnect the stock line). If everything looks fine, reconnect the factory gauge and have a little peace of mind. ![]()
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2003 GMC Sierra 1500 WT 1995 Nissan Hardbody 2016 Hyundai Veloster Turbo DC2 (SW/AW) Clyde W. Harvey USN "Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery" Winston Churchill |
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#10 | |
Sierra Grande Club
Join Date: Jan 2007
Location: New Mexico USA
Posts: 2,433
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Re: Oil pressure
Quote:
I agree and disagree, here’s why. If you know what your gauge reads normally it wont matter. IE: lets say it 20psi one calibrated gauge, and you factory gauge reads 3/4. As long as nothing changes then there is no problem. Agree? Here a problem with that statement. Does he know what it normally reads? Did it gradually get worse or did he change something and now it reads high? All theses questions need to be asked before we say it’s the gauge. JMO s/t
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1971 GMC Sierra Grande, 1/2 ton short wide, original 4 bolt 010 020 block & heads. (matching #'s). 383 stroker, SMI q jet 750 cfm, Lunati Voodoo 60102 cam, Scorpion roller rockers, Spin Tech pro street mufflers with X pipe. ![]() |
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#11 | |
Sierra Grande Club
Join Date: Jan 2007
Location: New Mexico USA
Posts: 2,433
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Re: Oil pressure
Quote:
![]() Is the stock location at the oil filter? s/t
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1971 GMC Sierra Grande, 1/2 ton short wide, original 4 bolt 010 020 block & heads. (matching #'s). 383 stroker, SMI q jet 750 cfm, Lunati Voodoo 60102 cam, Scorpion roller rockers, Spin Tech pro street mufflers with X pipe. ![]() |
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#12 |
Registered User
Join Date: Apr 2006
Location: MinneSNOWta
Posts: 1,381
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Re: Oil pressure
I don't think the factory location was by the filter, but then again, i've never seen a factory 67-72 chevy pickup.
The factory oil pressure location for every vehicle i've worked with is indicated in the picture below. ![]()
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2003 GMC Sierra 1500 WT 1995 Nissan Hardbody 2016 Hyundai Veloster Turbo DC2 (SW/AW) Clyde W. Harvey USN "Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery" Winston Churchill |
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#13 |
State of Confusion!
![]() ![]() Join Date: Jul 2002
Location: Gulfport, MS USA
Posts: 46,924
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Re: Oil pressure
That is the only place I remember seeing them on a small block also, back by the distributor.
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Bill 1970 Chevy Custom/10 LWB Fleetside 2010 Toyota Tacoma PreRunner SR5 Double Cab - DD Member of Louisiana Classic Truck Club (LCTC) Bill's Gallery Life isn't tied with a bow, but it's still a gift. Live simply. Love generously. Care deeply. Speak kindly. Leave the rest to God! |
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#14 |
Sierra Grande Club
Join Date: Jan 2007
Location: New Mexico USA
Posts: 2,433
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Re: Oil pressure
The reason I say this, is in the thread about oil leaks, some one mentioned it was by the oil filter. Not sure what to think though. I have a sending unit in that location on my truck.
Do you think that is the end of the oil path? I want to upgrade from my oil idiot light. s/t
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1971 GMC Sierra Grande, 1/2 ton short wide, original 4 bolt 010 020 block & heads. (matching #'s). 383 stroker, SMI q jet 750 cfm, Lunati Voodoo 60102 cam, Scorpion roller rockers, Spin Tech pro street mufflers with X pipe. ![]() |
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#15 |
Senior Member
Join Date: Oct 2006
Location: Edmonton Alberta
Posts: 458
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Re: Oil pressure
there is a passage above the oil filter on a small block but i never seen it used except for the fuel injected trucks. The others had the copper line behind the distributer
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#16 |
its all about the +6 inches
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,693
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Re: Oil pressure
the stock location for the guage, is as indicated in the photo. I am 99% sure the dummy light is the same. I have never noticed a small block with either of these located in any other location, new, old, or anything in between.
That guage should be rated for 60 PSI, which, is where the bypass valve should be rtated also. There is no sending unit for a mechanical guage. For a dummy lamp, or a later electrical guage, the sending unit would be on the spot indicated in the photo. ![]() Last edited by Longhorn Man; 02-24-2007 at 11:10 AM. |
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#17 | |
Registered User
Join Date: Apr 2006
Location: MinneSNOWta
Posts: 1,381
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Re: Oil pressure
Quote:
the Gen II engine in my 89 K-10 blazer had them, they came plugged from the factory. ![]()
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2003 GMC Sierra 1500 WT 1995 Nissan Hardbody 2016 Hyundai Veloster Turbo DC2 (SW/AW) Clyde W. Harvey USN "Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery" Winston Churchill Last edited by brak; 02-24-2007 at 11:13 AM. |
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#18 |
Senior Member
![]() Join Date: Aug 2004
Location: Centennial, CO
Posts: 2,956
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Re: Oil pressure
Is this a fresh rebuild? Are you running 20-50 oil?
With good bearing clearances and a high pressure or high volume oil pump you'll see the gauge peg like that. As long as the pressure isn't causing your rear main to leak I wouldn't worry about it. Better to have high oil pressure than low.
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ClusterTruck: 68 C10 Bought in 89, wrecked in 03. Slow low $ rebuild started '17. 6.0 & TKO http://67-72chevytrucks.com/vboard/s...d.php?t=788602 93 K1500 Short Step, 350, NV4500, EBL flash ECU. Vortec heads & roller cam someday... 05 Jeep Wrangler Unlimited. 3” lift & 6-speed 02 E320 the insurance total “free car” 13 Tahoe LTZ |
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#19 |
Registered User
Join Date: Feb 2006
Location: Oklahoma City
Posts: 588
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Re: Oil pressure
What grade of oil should be run in these trucks?
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1970 Chevy C10 "Under Construction" ![]() 2002 Chevy S10 V6 ![]() |
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#20 |
Parts and more parts
Join Date: Nov 2003
Location: Lebo, Kansas (middle of nowhere
Posts: 6,821
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Re: Oil pressure
On a lot of engines there is an oil pressure sending unit down by the oil filter. These, in most cases were used for switching items on and off (Example: ignition circuit of the power to an electric choke assembly). this sender connection is just after the oil filter in the flowpath and is at the front of the oil pressure galleys. The GM V-8 motor has an oil pressure tap on top of the block (as pictured above) just behind the intake manifold. This is the standard oil pressure indication connection. This takes pressure from the top end of the engine and the final galleys that oil goes to, so it is considered the END of the flowpath.
With ANY question on oil pressure, always go to the tried and true method--CONNECT a mechanical gauge and read it outside of the cab, then compare it to the ones in your dash. Go from there, know what you have, it may save your engine some day. The factory installed gauges are ususally off a fair amount, but you can compensate. What grade of oil do you want? That depends on what each person desires and likes. A lot of people are now looking at the Rotella-T oil for the protection to their camshafts since the newer oils are missing a lot of the zinc based additives. The weight depends on what you want and where you live--COLD as Hell, a lower weight will work better---HOTTER than the cold place, the weights can go up. GM always recommended a 5W-30 oil, but I have used 10W-30 weight for years. The important thing is to look at what the oils carry for additives and on a new motor from the car lot, you match the recommended items (warranty issues there). Last edited by piecesparts; 02-24-2007 at 02:18 PM. |
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#21 |
Firefighter
Join Date: Feb 2001
Location: Yellville, Ar, USA
Posts: 1,943
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Re: Oil pressure
I don't see any problem with that reading, mine runs there all the time. If it was running that far to the L or LOW side THEN I would be worried!!!!
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'72 Chevy SWB 350 Auto '67 GMC LWB 350 4 speed '70 Chevy 4x4 Stepside 350 Auto Yellville, Ar. USA ![]() ![]() Last edited by BLACK AND BLUE 67-72; 02-24-2007 at 01:01 PM. |
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#22 | |
1972 Shorty Owner
Join Date: Feb 2007
Location: Stationed in Cali , born and raised in PHX Arizona.
Posts: 796
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Re: Oil pressure
Quote:
Thank you all for the great tips and awesome response. I didnt think i would get this much help. You all kick a** in my book. Man i am glad i found this site. So i have decided to go pick up a new gauge and try that. Also i am pulling out the tranny today and getting it ready for rebuil ![]() Thx guy again everyone! -Hart
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1972 Chevy Shorty C-10- Project In Work http://67-72chevytrucks.com/gallery/...ATT1721941.jpg- New Project |
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#23 | |
Senior Member
Join Date: Jan 2005
Location: Loveland Co.
Posts: 3,098
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Re: Oil pressure
Quote:
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Chris 74 Custom Deluxe SWB 350/350/3.73’s 99 2wd Silverado RCSB 5.3/4L60/3.90’s http://www.classictrucks.com/feature...short_bed.html |
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#24 | |
its all about the +6 inches
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,693
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Re: Oil pressure
Quote:
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#25 |
Senior Member
Join Date: Apr 2000
Location: Delta,Pa
Posts: 14,950
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Re: Oil pressure
oil pressure like that is nothing to be concerned about.if it was reading really low i would worry but each line on that gauge is 15 psi 60 max. most of the relief springs are set at 80psi
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Owner of North Point Car Care in Dundalk Md. We specialize in custom exhaust on both modern and classic vehicles. We are a full service auto shop from classics to modern vehicles. Feel free to contact me with questions. I will give a 10% discount to any board member. |
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