Go Back   PowerStrokeArmy > Power Strokes > 94-97 Aftermarket

Thread Tools Display Modes
Old 05-04-2019, 04:43 PM
Peroni's Avatar
Peroni Peroni is offline
Member's Gallery
Join Date: May 2011
Location: North Carolina
Posts: 351
Default Electric Vacum Pump Conversion Finished

Since converting to hydroboost my vacuum pump only worked the HVAC controls. For years this worked fine and I never experienced any issues with the mechanical pump. Relocating my power steering reservoir next to the a/c compressor led to me looking to make some more room in this area. Taking out the mechanical pump sure would free up a lot of room here.

I want to add this warning before going further. The SD vacuum pump will not work if you have vacuum assist brakes! This is only for those who have already gone to hydroboost brakes. The little pump will run HVAC controls just fine but not your brake booster. There are electric vacuum pumps out there that will power both but that is outside the scope of this write up.

I chose to use a stock SD electric vacuum pump MC# BRPV7. Looking around I decided to put it behind the coolant expansion tank. Examining the bracket the easiest way to mount this was to bend the little bent tab so it was flat again and drill it for a M6 bolt. The expansion tank bracket was removed, the hole locations marked and drilled/tapped. The pump fits perfectly in this space with plenty of clearance for the hood spring. Next I removed the low vacuum switch and manifold from driver side fender, ditched the manifold and moved switch over to just behind the pump. As it is a very light part I used a single bolt in one of the holes that previously held the jack retainer clamp. Again it fits in the spot perfect.

A new vacuum check valve is required and I found MC# YG429 that was both the correct size and right number of barbs. A small tee was put in the line coming from the pump and I ran that branch to the low vacuum switch. A simple adapter was turned to step up to the larger hose size the switch uses.

Wiring was straight forward. I simply cut and spliced the vacuum switch connector and ran it across the engine bay along with the pump power and ground wires. The pump connector is MC # WPT169. This is a generic connector used in other places and has 4 wires, only 2 will be used here. I took power from the under hood fuse box for now, used an add a circuit on the trailer battery charging fuse. I'm not thrilled with the arrangement and will eventually add a dedicated fuse for the pump for a more factory look.

The pump has its own built in vacuum switch, it will cut on and off on its own. It did not run for very long to draw down the system and I got several cycles of my HVAC switch before the pump came on again. I can hear it hum in the cab with engine off but when the engine is running I couldn't hear it.

Now that the new pump is in place, what to do with the stock pump - its removal to free up space was the whole point of this endeavor. I read some old threads where the pump was removed and a shorter belt used. That would lead to less belt wrap on the a/c compressor and p/s pump neither of which I was happy about. I decided to make an idler using the old pump's bolt pattern and mounting bolts. The idler itself is MC # YS267 and is the same as the one above the tensioner. Used the same pulley bolt too. To compensate for the different pulley diameters I moved the idler position tangent to its contact point on the belt. The assembly fits and pulley lines up to the belt properly. Tons of room for my p/s reservoir now.

For a belt I'm using a Continental Elite 4081215X which is 121.5" long. Keep in mind I'm using a SD water pump pulley, the SD dual tensioner and DC Power alternator which has a smaller than stock pulley. With the new idler in place my tensioner indicates about 1/16 above the center mark which is exactly where it was with the mechanical pump in place.

So far I've put 300 miles on this conversion and no issues have come up. My new idler looks be working fine, belt is tracking straight and running silent. This was a fun little project that took about a weekend worth of working on it on and off. If you're looking to ditch the stock vacuum pump maybe this will give you a few ideas to try.
97 Green F-350 XLT 7.3L PSD 4x4 CC LB BTS E40D Manual Hubs 4.10 36000 miles when purchased 4/1/06. Mods - ISSPRO Performax gauges, Tymar intake, Tymar 3x4 DP to 4" ss exhaust, custom rear disc brakes, hydroboost conversion w/ 6.0 p/s pump, electric fuel, MANN CCV filter,LPF9750 oil bypass, 6.0 fan, tru-cool 4739, Swamps 200/30 injectors, Adrenaline HPOP, BASB turbo, Fluidampr, Spearco 6.0 cac.

05 Silver Mk4 Jetta GLS TDI
Old 05-04-2019, 06:47 PM
gnxtc2's Avatar
gnxtc2 gnxtc2 is offline
Member's Gallery
Join Date: Jun 2011
Location: Bergen County, NJ USA
Posts: 2,185

Looks awesome.

How much would it be to make the piece for the idler?

Billy T.
'97 Black F250HD SC, 3.55s, Punisher Trans, PI Converter, Dana 60 RSK w/ V & C SD springs, PIS 175/80s, T500, Cale's tunes, 910s, Smith Bros, ARPs, Fluidampr, IC, E-Fuel, 3" Plenums, CJC Traction blocks, HFHV IDM, T4/BASB, Horton, 268K
- 2016 F350 DRW Ultimate (stock for now )
- 1987 Buick Grand National (Staged)
- 2004 Mercury Marauder
- 1993 Geo Prizm (beater)
Old 05-05-2019, 02:03 AM
JCart JCart is offline
Member's Gallery
Join Date: Jun 2011
Location: Kamloops, British Columbia Canada
Posts: 467

Nice work Peroni, thanks for sharing, my to do list just keeps getting bigger....
Thanks again,
'97 F250 ECLB Tan White Tan Now ZF5 , 4:10s, D60, PMF 3.5 RSK, 37 Toyo RTs Anti sways front/rear w rear bags 5 blocks (184,000 Kms) DP, intake and 4 exhaust, FFD 205/30s, Hydra, E fuel.
Truck pix & Write ups
Old 05-21-2019, 12:16 PM
billmoody1 billmoody1 is offline
Member's Gallery
Join Date: Jun 2011
Location: texas
Posts: 6
Default idler

If there is any chance you would make the idler piece I would love to purchase one I have the screws and bolt and pulley already
1995 crewcab, 3-1/2 to 4 downpipe, tymar intake, coolant filter, 38 gallon tank, strictly diesel e-fuel,
Old 05-21-2019, 03:48 PM
kip4234 kip4234 is offline
Member's Gallery
Join Date: Aug 2011
Posts: 83

I want one also

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not 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

Forum Jump

All times are GMT -6. The time now is 09:43 AM.


Powered by vBulletin®
Copyright ©2000 - 2020, vBulletin Solutions, Inc.

Designed by Military Ltd