Vacuum headaches
Thread Starter
|
New User
Joined: Apr 2011
Posts: 16
Likes: 0
Vacuum headaches
Hi everyone, first time poster but long time follower and was wondering if someone could give me some advice. I have an 02 f250 and was having issues with the hubs not unlocking. I think I have read every thread on this topic so while trying to diagnose my problem, i unplugged the vacuum pump from the resevoir. Went inside the truck to see if the vents switched to the default defrost position and they did NOT. Everything worked as normal, but it was my understanding that the vent is controlled by the vac. Also, the vacuum pump itself seems quite loud and takes a while to pull enough vacuum to kick out by itself, even longer when its connected to the resevoir. I think the pump itself might be weak?? Appreciate if anyone could give me some insight here. Thanks
Fleet Mechanic
Joined: Jul 2005
Posts: 1,800
Likes: 52
From: Southern Colorado
The vents are vacuum controlled. The vacuum pump could indeed be weak - mine runs quite a while before shutting off. I installed manual hubs to solve the fail-to-unlock issue and love them. After I finish the Hutch mod, I may get to figuring out why my vacuum pump runs so long. Get yourself a good vacuum gauge and see how fast the pump can pull down the reservoir -that should give you some idea of the pump's performance.
Lead Driver
Joined: Sep 2007
Posts: 8,180
Likes: 669
From: Scio, OR
Are you sure that what you unplugged was the vacuum pump?
As I understand it, without vacuum the HVAC controls won't work. I'm not as familiar with a 7.3L, but perhaps there is a one way valve on the entrance to the reservoir that kept enough vacuum in it long enough to do your tests.
As I understand it, without vacuum the HVAC controls won't work. I'm not as familiar with a 7.3L, but perhaps there is a one way valve on the entrance to the reservoir that kept enough vacuum in it long enough to do your tests.
Cargo Master
Joined: Feb 2011
Posts: 3,450
Likes: 13
From: Forest lake minnesota
there are one way check valves in the system one test is to run the truck for a minute and shut it off. if you switch the functions on the heater control floor to defrost for example you will hear the doors moving even without the engine running that will work till you run out of vacume in the lines.
Thread
Thread Starter
Forum
Replies
Last Post
LSO1123
1999 - 2003 7.3L Power Stroke Diesel
4
Nov 14, 2011 05:33 PM
Opossum
1987 - 1996 F150 & Larger F-Series Trucks
2
Jun 16, 2010 04:42 AM
