Hey all,
I tried searching first. Seems my electric vacuum pump 6C3Z-2A451-BA is worn out on my '99 7.3. Vac motor runs fine but diaphram doesn't pull strong enough. I pulled the pump intake tube off the reservoir tank (isolating the pump) and plugged it with my finger and it couldn't pull strong enough to engage the cutoff switch. When I put vacuum to the switch using a different vac pump, it switched off and on fine. So I'm guessing the seals in the piston/diaphram are worn? A couple questions:

1) Are these pumps rebuildable? It seems all I need is the diaphram seal but I haven't been able to find any info on rebuild kits or seals. The reason I ask is I see some of the aftermarkets are labeled "reman" so I figure they might be rebuidable.

2) If I am buying new, I've heard nightmares about aftermarket replacements of these pumps. Anyone had this? Anyone know of an aftermarket that is decent?

Thanks
Jeff

 

Don't know about rebuild but I got mine new for $35

 

When you plugged the pump intake, did it stop? Then start again when the plug was moved? If that's the case, the pump would be working fine.

However, the Vacuum Pulse Module (VPM) may have an issue. Or, a leak somewhere in the circuit.

No, to my knowledge they are not re-buildable.

 

M-S-G
has your pump held up ok? how long you had it? is it loud? (just something I read)
thanks

 

whitetmw
when I pugged it with my finger it didn't shut off, vacuum felt weak. When I put a different vac pump to the switch, it shut off.

 

I see what your saying "said the Blind Man to his Deaf Wife". My Bad!

Sound like your pump. If it doesn't maintain 15 Hg" it's not going to do its job.

 

No worries thanks for the help! Anyone else have experience with aftermarket pumps?

 

I only had it for a year BUT it probably gets 5 years worth of usage during that time.
I have a medium vacuum leak that makes the pump on all the time.
To lazy to find it

Maybe someone will correct me but as long as you have hydroboost brakes the pump breaking is no big deal.

 

That's correct. Uses the Power Steering System for Hydraulics. The previous years had a Vacuum pump mounted specifically for the PS.

 

The pump breaking is no big deal unless you want to run your HVAC system on something other than defrost. The flapper that deflects the airflow to heat/panel/defrost works on vacuum and defaults to defrost in the event of a failure.

 

I replaced the vacuum pump & the 4x4 switch beside it as I was told of internal leaks causing problems , everything is working fine now , nice cold AC from my dash needed here in FL.
PROBLEM :the new pump never shuts off !!!
I have plugged both lines to the front hubs
plugged the line going to the dash , the only time the pump shuts off is if I put my finger over the suction on the pump , any ideas guys , pulling my hair out

 

You'll need to chase your leak one section of hose at a time. You have the pump shutting off there so that's a start. Run a piece of hose to the tank and plug the tank inlet. It might be the tank. Go from there.

 

 

I use a pair of medical forceps. They pinch off the hose and lock into place. When you pinch one and the pump stops.... you found the leak.

 

And one other thing...if you still have the vacuum operated hubs they won't work with a vacuum leak either.