Originally Posted by Junkman
You have a problem with that? Apparently.
Junkman: I have no problem when the information is correct. You said he didn't need to replace the pump. How do you know, until it has been tested? I never said the pump needed to be replaced. I was quoting the service manual. There are repair kits available to replace the seals, but I haven't had to repair the vane and rotor portion of a pump, so, I never looked in to a kit for that part of the pump.
I agree that the FSM is a very valuable tool to have, but some things have changed in the time since it was written. For example: now you can buy a seal repair kit(but not from Dodge) and a rebuilt pump. Pumps used to be $1200, now, I've seen rebuilts for $250. When I offered my suggestions, I was just trying to condense the information I had read into a short and simple version. Believe me, I will not be making any more suggestions to owners on here, about how they should take care of their trucks. I'll leave that to you.
Here is what the 2001 FSM, Section 7-35, that you said has the information he needs, about pump replacement:
The vacuum pump is not a serviceable component.
If diagnosis indicates a pump malfunction, the pump
must be replaced as an assembly. Do not disassemble
or attempt to repair the pump.
The combined vacuum and steering pump assembly
must be removed for access to either pump. However,
the vacuum pump can be removed without
having to disassemble the power steering pump.
If the power steering pump requires service, simply
remove the assembly and separate the two pumps.
Refer to the pump removal and installation procedures
in this section.
Vacuum pump output is transmitted to the
HEVAC, speed control, systems through a supply
hose. The hose is connected to an outlet port on the
pump housing and uses an in-line check valve to
retain system vacuum when vehicle is not running.
Pump output ranges from a minimum of 8.5 to 25
The pump rotor and vanes are rotated by the pump
drive gear. The drive gear is operated by the camshaft
DIAGNOSIS AND TESTING—VACUUM PUMP
The vacuum pump supplies necessary vacuum to
components in the following systems:
² HEVAC system
² Speed Control System
A quick check to determine if the vacuum pump is
the cause of the problem in any of these systems is to
road test the vehicle and verify that all of these systems
are fuctioning properly. If only one of these has
a vacuum related failure, then it is likely the vacuum
pump is not the cause.
A standard vacuum gauge can be used to check
pump output when necessary. Simply disconnect the
pump supply hose and connect a vacuum gauge to
the outlet port for testing purposes. With the engine
running, vacuum output should be a minimum of 25
inches, depending on engine speed.
DIAGNOSING LOW VACUUM OUTPUT CONDITION
If the vacuum pump is suspected of low vacuum
output, check the pump and vacuum harnesses as
(1) Visually inspect the vacuum harness for obvious
failures (i.e. disconnected, cracks, breaks etc.)
(2) Disconnect the vacuum supply hose at the vacuum
pump check valve. Connect vacuum gauge to
this valve and run engine at various throttle openings.
Output should be a minimum 25 inches of vacuum.
If vacuum is consistently below 25 inches, the
vacuum pump should be replaced.
If output is within
specified limits, the vacuum harness should be suspected
as the cause.
(3) Disconnect and isolate the vacuum supply harness.
Cap off open ends and apply roughly 15 inches
of vacuum to the harness. If the vacuum gauge does
not hold its reading, then there is an open in the harness
and it should be repaired or replaced.
(4) If the vacuum loss is still not detected at this
point, then the pump and harness are not the cause
of the low vacuum condition. Apply vacuum to the
related components of the vacuum supply system (i.e.
valves, servos, solenoids, etc.) to find the source of
the vacuum loss.