2nd Gen Non-Engine/Transmission help understanding ac+vac+p-steering

[DIESELWRKS]

ug, ug, could someone explain to me in potato head langauge on our trucks how the vacumm system and power steering and brakes and possible the ac is tied together. unless im really confused here. the truck seems even worse power wise with the ac on I know I need to replace my seal between the vac and powe-ster it doesnt leak to bad my steering fluid has been sucked up and new added. but is there something else I should check is the leaky seal causing these symptoms. hope this makes sense or I could be in left field and way off (usually). thanks. crayon drawings would help too





2002 HO 6-SPD LB 4X4 QC HTT 62/14 SB-FE TST PM3/*REVO-BETA*SMARTY MACH 4'S, RINGED AND STUDS, AFE/2 " 4"EXHAUST D/PRICOL GAUGES, FASS 150, VULCAN 1/2 DRAW-STRAW, 3/8 FUEL LINE, DSS-TRAC-BAR STEER-BOX, AIR BAGS,17'' KMC BLACK HOSS, 315/70/17 MICKTHOM MTZ'S 6" RCD LONG ARM LIFT AND DE-BADGED FOR FUEL MILEAGE. :-laf... THANKS RIP Source Automotive Light Truck Diesel Performance - Home

 

[steved]

The vac pump and PS pump are back-to-back, and gear driven (from the same gear if I remember correctly).



The PS pump also powers the "power assist" brakes (hydroboost). If you are turning and tap the brakes, sometimes you will get a jerk in the steering wheel (feedback).

 

[Vaughn MacKenzie]

The AC is separate, the compressor is on the opposite side of the engine down low on the passenger side.

 

[BDaugherty]

On the lower left corner of the engine, the vacuum pump is bolted to the back of the front cover where it is driven by an accessory drive gear which runs with the timing gears on the front of the engine. The power steering pump is driven off of the vacuum pump. The A/C compressor is separate. It is on the lower right side of the engine and is driven off the accessory drive belt.

The relationship: I don't see where the power steering pump comes into play for anything other than brakes and steering. The vacuum pump provides vacuum for all of the blend air door actuators in the HVAC system as well as working the cruise control (on earlier trucks) and the 4wd actuator.

 

[DIESELWRKS]

sorry for the delay on returning thread

thanks for the input. I guess my true question is since the vac/pum is busy with alot of it functioning. if a vac pump was going bad what would the signs be. my truck has 155k on it and to my knowledge the either pumps have ever been apart. I just wanted to know syptoms of this. thanks...

 

[WILLD420]

The vacuum lines have a tendency to leak from rotting rubber/cracked lines. If i remember right, the vacuum pump also has a little filter on it. Mine was nasty, with only 120K on it.

I bought the kit off ebay from GOULD? and redid the seal on the vacuum pump. When I had it apart, I cleaned it up good and it worked a lot better. The pump itself is just some plastic/nylon vanes inside a housing. If they get full of oil/gum they might quit working.

The whole job was about a 3 hour affair with time off to watch t. v and eat dinner.

 

[jelag]

The vacuum pump needs to pump down to about 25" of mercury... If you install a normal vac gauge as used on a car, you should see 25"... . If you don't see this low number... . say its 18... . than the pump is not doing its job and the accessories that run off of it might not work or will work slow...

I owned an 01, and several Fords all running a mechanical vacuum pump... we found that if you once a year if you pulled the hose and put 2-4 tablespoons of oil into the line and let it get sucked through the vacuum pump, it would lube and help seal the reed valves in the pump...

On the trucks with vac boosters for power brakes, this made the brakes work better, made the AC doors run better... . and all accessories work better... also if you have a pacbrake that runs from this vacuum the vacuum must be up for top performance...

As willd420 says above, any leaks will create problems as well... and leaks also allow dirt into the system to degrade the quality of the pump. .

 

[DIESELWRKS]

thanks looks to me a soon seal and hose fix soon befor winter. thanks.

 

[WILLD420]

Do it, you won't be sorry. Leaking oil at $11. 00+ a gallon pays for the seal pretty fast. Mine was pouring about a quart every couple hundred miles.