Auto 4x4 and Heater vacuum pump????? - Ford Powerstroke Diesel Forum
Powerstroke.org is the premier Diesel Truck Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 01-23-2011, 11:45 AM
Powerstroke.org Fanatic
 

Join Date: Dec 2007
Posts: 93
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Auto 4x4 and Heater vacuum pump?????

OK I need help in understanding how the auto 4x4 works. Here is what happened. Heater controls where working fine but not the auto 4x4. Found one of my vac lines cracked. Ran all new lines from pump to both 4x4 hubs. Put in 4x4 and did not engage. Hooked up a vacuum gage and the pump is pulling 11" on the gage at both hubs. Hook the hubs back up and nothing happens. My question is how does this work? When I had the gage hooked up it would draw to 10" and then all of a sudden I would here a click and vacuum would go to 0, but the pump keeps running for a few seconds and then shuts off. Thought it was the vacuum solenoid switch so I replaced with a new on and it does the same thing. Pulls vacuum to the hubs and then all of a sudden "click" and no vacuum, but when I turn the 4x4 switch off the vacuum goes to about 3". It does this just for the auto 4x4. The whole time the heater controls work fine. I don't know if this is normal operation or what. Is this how it is supposed to work? Any suggestions will help. Thank you

Kyle
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2  
Old 01-26-2011, 05:14 AM
Member
 

Join Date: Jan 2011
Posts: 86
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
+1
I have been having a issue aswell to where heat controls working then when i was sitting in a dirt parking lot yesterday rear wheels started to spin i switch to 4wd and only rear spin, i switch to 4x4 low and still only rear spin. Does yours engage if ou manually lock the hubs?
Reply With Quote Quick reply to this message
  #3  
Old 01-26-2011, 02:23 PM
Powerstroke.org Fanatic
 

Join Date: Dec 2007
Posts: 93
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Yes mine does lock with the man. hubs. Here is what I found out by a mechanic. Truck has to be moving for it to go into 4X4. Don't have to move much but it does have to a little. Here is what I found on my truck. So I found front bearing was bad and also the o-ring that seals the vacuum at the hub. Replaced the o-ring, bearing and seals. Now I had 10" of vacuum at both hubs. So To test i turned switch to 4x4. Vacuum pump came on and pulled 10" at hubs then solenoid clicked vacuum went away. turned switch 4x4 off and vacuum went to 3". This must be how it works because I pulled my truck out of my shop put it in 4x4 and everything worked. Still do not know how it exactly works but If you have vacuum at both hubs and truck is rolling then it should work. I would check the vacuum at you hubs. Sorry for the long reply. Hopefully this helps.
Reply With Quote Quick reply to this message
  #4  
Old 01-27-2011, 06:57 AM
Member
 

Join Date: Jan 2011
Posts: 47
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
interesting.... i have an 03 f250, my heater only blows out defrost. figured it was vacuum related. i unplugged he vacuum supply to front hubs and plugged lines from pump and heater works perfectly, soon as i plug lines back in... heater flakes immediately.

figured i have a bad vacuum line to hubs somewhere, i had a look around but.... how do you unhook vacuum lines at hubs, i didn't wanna just start pullin on em.

how hard is it to replace those o rings?

any help is greatly appreciated as my feet are freezing in that thing..
Reply With Quote Quick reply to this message
  #5  
Old 01-27-2011, 08:40 AM
Powerstroke.org Fanatic
 

Join Date: Dec 2007
Posts: 93
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Quote:
Originally Posted by tpar1220 View Post
interesting.... i have an 03 f250, my heater only blows out defrost. figured it was vacuum related. i unplugged he vacuum supply to front hubs and plugged lines from pump and heater works perfectly, soon as i plug lines back in... heater flakes immediately.

figured i have a bad vacuum line to hubs somewhere, i had a look around but.... how do you unhook vacuum lines at hubs, i didn't wanna just start pullin on em.

how hard is it to replace those o rings?

any help is greatly appreciated as my feet are freezing in that thing..
Well to unhook the vacuum lines at the hubs I just pulled on them. I did break one and had to go to the auto parts store and get new lines. I just got a cheap vacuum gauge and t-ed into it hooked it up to the hub to get a reading. I blocked off the other hub and did them one by one to find wich one was bad. Passenger side was working but the driver side was not. To change the o-ring you have to pull the front bearing assembly out and there is a yellow o-ring on the bearing assembly. Can't miss it. Also there is an inner seal behind the bearing asembly that could be bad too. Mine was, so I replaced it. They are kinda hard to get out and put back. It is a wierd 2 piece looking seal. Getting the bearing assembly out and getting to the inner seal is not too bad. I changed a few bearings on my truck. I can have it all apart in less than a 1/2 hr. Did it in my garage. Hope this helps.
Reply With Quote Quick reply to this message
  #6  
Old 01-27-2011, 08:44 AM
Member
 

Join Date: Jan 2011
Posts: 47
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Quote:
Originally Posted by Kyle_1724 View Post
Well to unhook the vacuum lines at the hubs I just pulled on them. I did break one and had to go to the auto parts store and get new lines. I just got a cheap vacuum gauge and t-ed into it hooked it up to the hub to get a reading. I blocked off the other hub and did them one by one to find wich one was bad. Passenger side was working but the driver side was not. To change the o-ring you have to pull the front bearing assembly out and there is a yellow o-ring on the bearing assembly. Can't miss it. Also there is an inner seal behind the bearing asembly that could be bad too. Mine was, so I replaced it. They are kinda hard to get out and put back. It is a wierd 2 piece looking seal. Getting the bearing assembly out and getting to the inner seal is not too bad. I changed a few bearings on my truck. I can have it all apart in less than a 1/2 hr. Did it in my garage. Hope this helps.
yes it does... thanks. so auto zone sells the entire plastic vacuum line/tube as one piece deal, pre bent oem fit? or you bought a roll and cut to length?

thanks again.
Reply With Quote Quick reply to this message
  #7  
Old 01-27-2011, 08:53 AM
Powerstroke.org Fanatic
 

Join Date: Dec 2007
Posts: 93
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Quote:
Originally Posted by tpar1220 View Post
yes it does... thanks. so auto zone sells the entire plastic vacuum line/tube as one piece deal, pre bent oem fit? or you bought a roll and cut to length?

thanks again.
I just bought it off the roll. Bring a piece of your old to match it up. I think its 1/8 " line. By some t's for testing
Reply With Quote Quick reply to this message
  #8  
Old 01-29-2011, 02:08 PM
Member
 

Join Date: Jan 2011
Posts: 47
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Quote:
Originally Posted by Kyle_1724 View Post
I just bought it off the roll. Bring a piece of your old to match it up. I think its 1/8 " line. By some t's for testing
ok.. so today i removed the vacuum lines from hubs to top (it was all one piece), i then checked for leaks.... there were none, the lines are ok. i also checked hubs, also no leaks. then i checked lines from electric pump to pulse vacuum hub lock solenoid.... all are ok. put it all back together and still heat wont work right.

the only way i can get heater control to work is if i plug this off like so..



it works fine as long as this plug is blocked off..

any more ideas?
Reply With Quote Quick reply to this message
  #9  
Old 01-29-2011, 08:09 PM
Powerstroke.org Fanatic
 

Join Date: Dec 2007
Posts: 93
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
How did you check the hubs for no leaks? What I would do is hook up everything and then take off the vac lines at the hubs and block both of them. If that works then It sould be one of your hubs. If still doesn't work them I'm stumped as well. How did you check the puls solenoid? Did you try and block off the main lne gonig to the hubs before it t-s off to bloth hubs?
Reply With Quote Quick reply to this message
  #10  
Old 01-30-2011, 06:30 AM
Member
 

Join Date: Jan 2011
Posts: 47
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
well, i removed the complete line as one piece... if i had known how easy it was to check i would not have removed it. but once removed i cappped off two of the ends and put the vacuum pump on 3rd end... it held vacuum, so line is ok.

i then put vacuum pump directly on hub itself, it took a lil longer to pull a vacuum, but once it did... it held, and did exactly same thing on other hub. so i assume they are ok.

i don't know how to check pulse solenoid, so maybe thats the problem... i dunno. but i removed lines and checked em for leaks, never found a bad line. the only way i can heat to work right is to block off that connector... just like it is in pic.

i am stumped too.
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Ford Powerstroke Diesel Forum forums, you must first register.
Please enter your desired user 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.



Thread Tools
Display Modes

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



All times are GMT -8. The time now is 06:21 AM.


Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.1
Garage Plus, Vendor Tools vBulletin Plugins by Drive Thru Online, Inc.

vB.Sponsors