fuel pressure shut-off using oil sending unit? - 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> Electrical
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 06-19-2005, 06:38 PM
NXS's Avatar
NXS NXS is offline
wind & fire = guides to power
 
Last photo:
Join Date: Nov 2004
Location: Oklahoma
Posts: 1,534
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
fuel pressure shut-off using oil sending unit?

I am looking for a common oil pressure sending unit that will ground out when the pressure drops below 4 PSI (dummy light system).
I would like to run this on me fuel line pressure side and allow it to ground my tach wire to kill the ignition system in the event of low pressure.

Is this workable? Does Anybody know of a sending unit that cycles at 4 psi?

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 06-19-2005, 08:05 PM
docvette's Avatar
Hotrodders.com Moderator
 
Last wiki edit: Rebuild an alternator Last photo:
Join Date: Mar 2004
Location: Lafayette, california
Age: 62
Posts: 7,362
Wiki Edits: 12

Thanks: 0
Thanked 6 Times in 3 Posts
Fuel Pressure???

Doc here,

I see all kinds of issues here..

FIRST, what Vehicle/Engine Combo are we dealing with here?

IS It Confuserized??

IS it a Standard HEI? Or other Hot Ign??

If you go grounding the tach, your headed (depending on what configuration you actually have) For ECM failure, Confuser Buffer/Driver Failure, or Coil Failure...or at least (if you have one,) Coil fuse blow outs..

If it is Confuserized .. and you ground the tach pulse (on GM 's anyway) You are HARD grounding the Reference pulse going back to the brain box..While it will Surely Stop the engine..Is hard on the Buffer / Driver inside the Cornfuzzer...And just maybe, Next time It won't Start again, Ever... (or until you replace the confuzzer)

The BEST set up..from your junk box...is as follows..get a 0 to 30 ohm pressure sender (pre 65 GM,you may have to experiment with up to 0 to 290 ohm senders to get your correct combo of 4 psi and enough resistance to fire /or /not fire the relay..), You may even be able to get a 4 PSI (or adjustable) pressure switch from an industrial Compressor supply house ,...and a relay...

Wire your Coil power and Coil through the relay...

To test or calibrate, put a copper shut off valve between the block and sender, pinch the valve down to 4 psi on the gauge..then adjust your total resistance for the relay coil (You may have to add resistors to get it exact..suggest 5 watt Ceramic's..starting at 100 ohm going up 50 ohms in each increment, you can get these at rat shack or Fry's..)To where the relay fires (or unfires, depending on how you actually hook it up) at that point..

Remove, or open the valve, and you should have it!

Be sure your Secondary Ignition is in tact and AFTER the relay..or it won't start on a zero psi engine until pressure is up..

Doc
__________________
Aftermarket Solutions
Electronic & Electrical
Innovations
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 06-24-2005, 10:38 AM
Member
 
Join Date: Dec 2004
Location: Madison, WI
Posts: 1,885
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Echlin makes them and I run one to cut the voltage to the pump. I don't have the part number but if you aks to look through the Echlin parts book they will have pics and specs on all the oil pressure sensors available. I do run this through a relay as well. Don't ask how I wired it though as I couldn't begin to expain it. I run a FAST EFI system as well as nitrous so it's looking at a few more things in addition to the oil pressure.
Reply With Quote Quick reply to this message

Recent Electrical 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:
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
high oil pressure HELP PLEASE! RDavis81 Engine 8 03-25-2009 07:44 PM
oil change- step by step instructions for women and men Fireball Hotrodders' Lounge 38 08-30-2008 08:39 AM
Fuel sending unit won't read RodFather Electrical 3 05-22-2005 06:02 PM
73 Pontiac Firebird Fuel Pickup Sending Unit Rad Ray Engine 3 02-05-2003 09:39 AM
Oil Sending Unit Assistance MI2600 Engine 3 09-11-2002 08:55 AM


All times are GMT -6. The time now is 03:33 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.