The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1969 - 1972 Blazers and Jimmys Message Board > 1969 - 1972 Blazers and Jimmys Projects and Builds

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 07-24-2013, 12:13 PM   #1
mtully79
Registered User
 
mtully79's Avatar
 
Join Date: Apr 2007
Location: Acworth, GA
Posts: 441
Oil pressure question

Oil pressure at near peak when I first start it up, then falls slowly over the course of 15-20 mins. It's only started doing it the last 2 or 3 trips after having on the road for the past 3 months. I only take her out on weekends around town, so she's not a daily driver. Any ideas?
mtully79 is offline   Reply With Quote
Old 07-24-2013, 01:00 PM   #2
jaros44sr
Senior Member
 
jaros44sr's Avatar
 
Join Date: May 2006
Location: Philadelphia, Pa. 19454
Posts: 9,761
Re: Oil pressure question

Quote:
Originally Posted by mtully79 View Post
Oil pressure at near peak when I first start it up, then falls slowly over the course of 15-20 mins. It's only started doing it the last 2 or 3 trips after having on the road for the past 3 months. I only take her out on weekends around town, so she's not a daily driver. Any ideas?
May be just the viscousity of your elixior, since it is hot out now, maybe the ambiant temp. and engine temp. are affecting it....what weight oil are you using?
__________________
Semper Fi...Uncle Sam, you da man

All parts offered to help are free, unless otherwise noted

Dont try this stuff in my build thread, unless you have 55 years of mechanical OTJ training
SAFETY FIRST

AS usual, off topic

They say your mind goes second, can't remember the first


Jim
jaros44sr is offline   Reply With Quote
Old 07-24-2013, 01:18 PM   #3
vegadesign
Registered User
 
vegadesign's Avatar
 
Join Date: May 2012
Location: murfreesboro, TN
Posts: 743
Re: Oil pressure question

sounds like the oil is heating up to quick
may need heavier oil depending on what your weather is like
what engine and setup do you have?

low viscocity oil will start to do that when its running for while because the heat thins it oil making it harder for the oil pump to pick it up
__________________
"its not a hobby, It's a Lifestyle"
.
bagged and soon to be bodied 70 longbed
http://67-72chevytrucks.com/vboard/s...d.php?t=564028
vegadesign is offline   Reply With Quote
Old 07-24-2013, 03:32 PM   #4
mtully79
Registered User
 
mtully79's Avatar
 
Join Date: Apr 2007
Location: Acworth, GA
Posts: 441
Re: Oil pressure question

I'm running 10w-40 synthetic oil. I've got a 350 in there, temps have been higher here at the beach the past month as well. Truck is garage kept out of the sun, oil pressure shoots up as soon as I turn the key.
mtully79 is offline   Reply With Quote
Old 07-24-2013, 04:27 PM   #5
vegadesign
Registered User
 
vegadesign's Avatar
 
Join Date: May 2012
Location: murfreesboro, TN
Posts: 743
Re: Oil pressure question

so im assuming its running about 45-60 psi at idle?
after about 15 min or so of driving around at higher rpms it drops down?
__________________
"its not a hobby, It's a Lifestyle"
.
bagged and soon to be bodied 70 longbed
http://67-72chevytrucks.com/vboard/s...d.php?t=564028
vegadesign is offline   Reply With Quote
Old 07-24-2013, 09:04 PM   #6
mtully79
Registered User
 
mtully79's Avatar
 
Join Date: Apr 2007
Location: Acworth, GA
Posts: 441
Re: Oil pressure question

Yea it drops down to normal level after driving for 15 mins. Engine idles at 700 rpm.
mtully79 is offline   Reply With Quote
Old 07-26-2013, 10:59 AM   #7
magicoolbus
Registered User
 
magicoolbus's Avatar
 
Join Date: Jul 2010
Location: Mesa, AZ
Posts: 513
Re: Oil pressure question

The factory oil pressure gauge is indeed a 60 psi unit, unless someone along the way swapped in an 80 psi one (found on larger trucks). The best thing to do if your worried is to get a calibrated oil pressure gauge and hook it up and see what psi's you are actually running. A fresh rebuild with tight oil clearances can easily be 60 to 80 psi.
__________________
JB from AZ
1969 Chevy Sub K10
1957 Chevy 3200
1962 VW Beetle
1957 Willys CJ5
magicoolbus is offline   Reply With Quote
Old 07-26-2013, 01:06 PM   #8
mtully79
Registered User
 
mtully79's Avatar
 
Join Date: Apr 2007
Location: Acworth, GA
Posts: 441
Re: Oil pressure question

Great info, I'll hook it up and see what it reads.
mtully79 is offline   Reply With Quote
Old 07-16-2016, 12:03 PM   #9
JDSurge
Registered User
 
Join Date: Oct 2014
Location: Lexington, Kentucky
Posts: 67
Angry Re: Oil pressure question

Hello everyone. I need some help with my oil pressure port. I have a rear seal leaking and didn't want to take out the transmission right now so I used some Lucas rear seal to fix it. At about the same time, my distributor when out (changed almost every part in it and still didn't fire) so I bought a MSD street fire distributor and it fired right up.
My question is: I now have no oil pressure reading on my new gauge. I removed the oil pressure sending unit at the same time I installed the MSD and there was no oil at the port or in the line. Could the rear seal stop leak have clogged up the oil port at the rear top of the engine, next to the distributor? Or do I have the distributor on wrong or bought a wrong distributor? The gauge was working before all this started but I was reading some threads about the ring around the distributor sending oil to the top end and now I'm wondering if I bought the right distributor.
I have a 350ci out of a 1977 blazer with HEI distributor.
Thanks for any advice to fix this.
JDSURGE
ALso posted a new pic of my blazer with the top off finally. Unfortunately, I went out to a Rod Run party last night and it rained in it for about 20 mins. I hope it will dry out OK.
__________________
JDSurge is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 09:11 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com