Low oil pressure on SBC - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 10-24-2008, 11:56 AM
lg1969's Avatar
Google "Tunnel Ram 406"
 
Last photo:
Join Date: Oct 2007
Location: Bohemia, L.I.N.Y.
Age: 64
Posts: 1,059
Wiki Edits: 0

Thanks: 1
Thanked 21 Times in 18 Posts
Low oil pressure on SBC

A long time ago I had a problem with my 307 sbc with low oil pressure. I rebuilt the 307 with new crank bearings, and replace with a high pressure oil pump. Once I had the 307 together and had it running, the oil pressure was very low at 40psi cold, and 5-10psi hot. It should read 80 psi cold, and 40psi hot. I discovered the distributor was cause of the problem. The oil travel around the groove of the distributor housing then through the lifter gallery was leaking. I replaced the distributor with another one and to my supprise the oil pressure jumped up 80psi cold and 40psi hot. If any of you guys have low oil pressure on your sbc, before you take the block apart, check the distributor.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 10-24-2008, 01:51 PM
Jmark's Avatar
Registered User
 
Last photo:
Join Date: Sep 2003
Location: phoenix
Age: 61
Posts: 4,824
Wiki Edits: 0

Thanks: 0
Thanked 3 Times in 3 Posts
That's a good tip! If the dist. housing was wobbling around a little, over time it could loose it's size and leak a lot of oil right back into the pan.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 08-07-2010, 01:12 PM
Registered User
 
Join Date: Aug 2010
Location: crossville tn
Posts: 2
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
??

what do you mean by the housing was leaking?? i have a 350 and has very low oil pressure. change the oil from 10.30 to 20.50 and pressure comes up everywhere. just wanted to check about the distrib housing. problem thanks
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 08-07-2010, 01:14 PM
Registered User
 
Join Date: Aug 2010
Location: crossville tn
Posts: 2
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
??

also on that note how old was your distributor that was the problem one
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 08-07-2010, 01:45 PM
cobalt327's Avatar
WFO
 
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Location: Atlanta
Age: 59
Posts: 5,037
Wiki Edits: 1616

Thanks: 128
Thanked 597 Times in 546 Posts
Quote:
Originally Posted by 19791980camaro!!
what do you mean by the housing was leaking?? i have a 350 and has very low oil pressure. change the oil from 10.30 to 20.50 and pressure comes up everywhere. just wanted to check about the distrib housing. problem thanks
The distributor body forms part of the oil passage- that's the "groove" seen down near the gear in the photo below. If the dist. body was machined undersized or was damaged/excessively worn, this would create an internal oil leak from the groove that would dump oil back into the pan- and might also lower the oil pressure.

Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 05-28-2013, 11:23 AM
Registered User
 
Last photo:
Join Date: May 2013
Posts: 109
Wiki Edits: 0

Thanks: 7
Thanked 5 Times in 3 Posts
Damn I know this is a old post but I think this my be my problem also. New motor doing the same thing.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 05-28-2013, 12:27 PM
Registered User
 
Last photo:
Join Date: Apr 2007
Location: Seattle, Wa
Posts: 6,856
Wiki Edits: 0

Thanks: 4
Thanked 459 Times in 394 Posts
Quote:
Originally Posted by TylerS10 View Post
Damn I know this is a old post but I think this my be my problem also. New motor doing the same thing.
If you look at the picture above your post you will see the distributor has a grrove in the bosses above and below the oil groove passage. This is not necessary but probably isn't large enough to result in the problem.

You need to be sure the distributor is fully seated. If it catches the pump intermediate drive shaft just wrong, it will turn the pump but will be positioned to either obstruct the lifter galley and/or expose a leak back to the pan.

Bogie
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 05-28-2013, 12:35 PM
lg1969's Avatar
Google "Tunnel Ram 406"
 
Last photo:
Join Date: Oct 2007
Location: Bohemia, L.I.N.Y.
Age: 64
Posts: 1,059
Wiki Edits: 0

Thanks: 1
Thanked 21 Times in 18 Posts
Well, this problem happen to me again and it happen the second time on my 406 sbc.
Who says lighting does not hit you twice.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 05-28-2013, 01:26 PM
Registered User
 
Last photo:
Join Date: May 2013
Posts: 109
Wiki Edits: 0

Thanks: 7
Thanked 5 Times in 3 Posts
Now that I think about it my MSD 85551 had o rings and was told to take them out. Did not have this problem til I did that.
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 05-28-2013, 03:56 PM
lg1969's Avatar
Google "Tunnel Ram 406"
 
Last photo:
Join Date: Oct 2007
Location: Bohemia, L.I.N.Y.
Age: 64
Posts: 1,059
Wiki Edits: 0

Thanks: 1
Thanked 21 Times in 18 Posts
Bad mistake.
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 05-28-2013, 03:57 PM
cobalt327's Avatar
WFO
 
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Location: Atlanta
Age: 59
Posts: 5,037
Wiki Edits: 1616

Thanks: 128
Thanked 597 Times in 546 Posts
Quote:
Originally Posted by TylerS10 View Post
Now that I think about it my MSD 85551 had o rings and was told to take them out. Did not have this problem til I did that.
That might be an indication that your block was machined for use w/the O-rings; a factory production block isn't meant to use them unless modified for them.

BTW, the tops of the castings should be chamfered to allow the O-rings to slide into position w/o damaging them.
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 05-28-2013, 05:01 PM
Registered User
 
Last photo:
Join Date: May 2013
Posts: 109
Wiki Edits: 0

Thanks: 7
Thanked 5 Times in 3 Posts
Quote:
Originally Posted by cobalt327 View Post
That might be an indication that your block was machined for use w/the O-rings; a factory production block isn't meant to use them unless modified for them.

BTW, the tops of the castings should be chamfered to allow the O-rings to slide into position w/o damaging them.
Yea that block came from a friend and was sitting for 10 years who knows what was done to it. 70's something block just said 350 on the casting. I had the machine work done a long time before I purchased the rotating assemble.
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 05-28-2013, 06:03 PM
Richiehd's Avatar
JS-70
 
Last photo:
Join Date: Jun 2011
Location: Jupiter FL
Posts: 854
Wiki Edits: 0

Thanks: 166
Thanked 58 Times in 51 Posts
Quote:
Originally Posted by TylerS10 View Post
Now that I think about it my MSD 85551 had o rings and was told to take them out. Did not have this problem til I did that.
If I remember right, your motor was eating up distributer gears, that's why the o rings were removed. Maybe that housing is undersize, compared to a non oring housing?
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 05-28-2013, 06:58 PM
Registered User
 
Last photo:
Join Date: May 2013
Posts: 109
Wiki Edits: 0

Thanks: 7
Thanked 5 Times in 3 Posts
Quote:
Originally Posted by Richiehd View Post
If I remember right, your motor was eating up distributer gears, that's why the o rings were removed. Maybe that housing is undersize, compared to a non oring housing?
Yea it was the end play on the gear that caused the timing to jump. The gear was walking up and down on the cam. I did that first and the o rings second when the new gear came in. The timing is rock solid now just the oil pressure problem now. Its always something so far.
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 05-28-2013, 07:44 PM
Richiehd's Avatar
JS-70
 
Last photo:
Join Date: Jun 2011
Location: Jupiter FL
Posts: 854
Wiki Edits: 0

Thanks: 166
Thanked 58 Times in 51 Posts
10 psi for every 1000 rpms for SBC. I cut a small groove in mine and still have 30 psi hot oil pressure idling.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may 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
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
low oil pressure... gearhead81 Engine 13 03-12-2009 06:54 PM
fram oil filter lower oil pressure elvis 66 chevelle Engine 33 09-14-2006 04:36 PM
low engine pressure molevolent_creations Engine 14 12-24-2005 07:49 PM
Help 350 rocket bad timing chain & low oil pressure? 71oldsmann Engine 2 03-14-2005 11:45 PM
Low Oil Pressure on Buick 3.8L V-6 TravisT Engine 8 03-31-2004 10:12 AM


All times are GMT -6. The time now is 03:52 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.