HESCO Supercharger installation instructions for a 1993 ZJ


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HESCO Supercharger installation instructions for a 1993 ZJ (Grand Cherokee)

Note These instructions are derived from the original HESCO instructions. They have been modified by me based on the problems I have encountered in the installation process. Even that does not guarantee I didn’t miss something. Read both sets, it can’t hurt. Douglas W. Wilson.

THINGS YOU WILL NEED!

Jeep Service Manual (for torque specs etc.)
Torque Wrench (for the pulley, and other bolts)
Deep well 10mm for the throttle body
Small set of wrenches for the casting
Set of allen keys for the casting
5/16 hex drive for the superchargers bolts
T-50 Torx bit if you have to take the seatbelts off to run the boost-a-pump
Bottle of power steering fluid
¼ inch plastic vacuum T fitting
¼ inch plastic vacuum splice
A few nice days, an understanding friend , and a spare vehicle just in case… J

TEAR DOWN:

1 - Remove rubber air duct from throttle body, unclamp air-box hat to expose air filter, unplug the two breather lines from the air-box hat and remove the duct and air-box had as a unit.
2 - Loosen the power steering pump and remove the drive belt and top pivot bolt. Next remove the long 3/8" mounting bolt just to the left of the pivot bolt. Remove the power steering pump. And reservoir.
3 - Disconnect the fittings and remove the throttle body. (NOTE: stuffing a rag in the hole keeps things from falling in)
4 - Remove the bracket that holds the throttle body and transmission cables from the intake manifold.
5 - Remove all five of the vacuum fittings from the intake manifold (one at the front, four at the rear, and one where the brake booster ties in by the throttle body).
6 - Relocate the MAP sensor fitting to the rear most hole. (MAP sensor is the one mounted to the fire wall just behind the intake manifold)
7 - Move the MAP sensor rearward and attach it to the brake line using the two larger tie wraps provided. You will have to pull 3 or 4 inches of wire out of the harness to make it fit.
8 - Splice the pressure sensor included in the boost-a-pump kit into the MAP sensor line I used the connector from the front (the one with two pipes) so I could mount the MAP and Boost-a-Pump sensor to it.
9 - Relocate the MAT sensor (the one that has wires) to the intake side of the super charger. (same side as the throttle body)
10 - Use the plugs from the supercharger to plug the remaining rearward holes in the intake manifold. Leave the front hole open for now.
11 - Put the brake vacuum attachment in the hole to the drivers side of the supercharger and fill out the remainder with the smaller attachments.
12 - Remove the center valve cover bolt from the passenger side of the valve cover and the one just forward of it. (the third and fourth bolt from the front)
13 - Uncap the valve on the fuel rail and relieve the fuel pressure.

CAUTION

GASOLINE IS HAZARDOUS, WEAR EYE PROTECTION AND NEVER WORK ON A HOT ENGINE OR AROUND FIRE OR FLAME. THE FUEL IN THE ZJ IS UNDER PRESSURE ALL THE TIME)

14 - Unplug the RETURN fuel line from the fuel rail. (This is the line that connects to the pressure regulator on the forward end of the fuel rail)

ASSEMBLY:

1 - Locate and run the Kenne-Bell boost-a-pump electronics. (The wire is 14 Gauge Orange with a Black stripe and exits the vehicle just under the rear seat to the left of the seat latch. You can see where it goes out by looking under the vehicle just forward of the fuel tank) If you don’t have room under the seat, remove the plastic door just aft of the tire carrier and there should be a metal brace that will accommodate the electronics) (If you have to extend the power wires use 10 Gauge stranded)
2 - Locate the control head for the boost-a-pump (just under the dash left of the VIC is a good spot)
3 - Run the wire with the RCA plug to the control head.
4 - Run the wire with the two spade terminals through the bulkhead plug. (up just to the right of where the accelerator cable exits)
5 - Put the fuel warning stickers on (one by the fuel gauge and the other by the filler)
6 - Install the wedge shaped adapter onto the intake manifold with one of the new gaskets. Put Locktite on the bolts and torque to 120 inch pounds.
7 - Replace the stock steering pump reservoir with the one provided. Reattach the pressure line and orient it so it is tight to the back of the reservoir.
8 - Install the new throttle body on the superchargers intake manifold using the new gasket and fasteners supplied. Orient the throttle body so that the linkage will be on the passenger side of the vehicle (right side). (note. If the ear on the left side of the vacuum port isn’t trimmed back it will hit the valve cover. Check fit the supercharger and trim the throttle body as required)
9 - Install the two aluminum stands into the valve cover bolt holes. (NOTE: One is shorter to go through the spark plug wire loom) and bolt the throttle linkage bracket provided. (The two short legs should be up). (in my case one wasn’t shorter, so I added washers to take up the extra space. Or you could cut it.)
10 - Replace the idler to the right of the A/C compressor with the one supplied in the kit. (if required)

TEST FIT THE SUPERCHARER!
Mark where it aligns
then come back here and follow the directions with the anaerobic sealer.

10 - Install the supercharger assembly onto the engine using the anaerobic sealer between the mating surfaces. (DO NOT TIGHTEN THE BOLTS TILL INSTRUCTED TO DO SO.)
11 - Install the front compressor shaft brace over the compressor shaft and the front left head bolt. (Don’t take the existing bolt off) Attach with the nut provided and reinstall the power steering pump with the long 8mm bolt that replaces the power steering pump pivot bolt. Install the long 3/8" countersunk mounting bolt in the power steering pump bracket and through the lower hole in the compressor shaft brace. Tighten the set screw in the brace where it slips over the compressor shaft.
12 - Install the new drive belt provided. Route the belt as shown below. Back off all adjustment on the power steering pump. The new idler has an eccentric shaft. Adjust this shaft for maximum contact with the power steering pump and tighten the bolt to 30 foot pounds. Tighten the belt to stock tension.
13 - Install the throttle cable, cruise control cable, and transmission cable into this bracket and attach to the throttle body.

NOTE:

If the throttle plate is open a bit then your supercharger isn’t forward enough. Loosen the bolts under the supercharger and the set screw and slide it forward if possible.

(NOW, TIGHEN THE BOLTS ON THE SUPERCHARGER MOUNTING BRACKET)

MARK where everything aligns, go back to step 10 and use the anaerobic sealer.

14 - Install the fuel pressure regulator by attaching the black female connector (on the regulator) to the same port you disconnected the fuel bypass line from. Clamp the regulator to the injector fuel rail with the ¾" clamp on the regulator bracket. Attach the original female connector to the short line. Install the ¼-90 fitting in the front port of the stock intake manifold (under the supercharger shaft). Connect the small line on the back of the fuel pressure regulator to the 4-way plastic connector. Attach the fitting, stock regulator, and new regulator with the vacuum hose and 4-way connector provided. (NOTE: The extra connector is for a boost gauge of your choice) (You’ll need a shorter female line. If the regulator doesn’t have one call HESCO)
15 - Remove the air filter element and the rear most screw from the bottom of the box. Tilt the box up and install the 1" spacer underneath. Replace the bolt with the longer bolt provided and tighten. Now here is where I made a small change to get things to fit better. I cut the 1" spacer to ¾" and used the remaining ¼" under the left most bolt at the front. This provided a little more clearance and allowed the hood to actually close.
16 - Take the 6" piece of wire reinforced hose and slip it inside the stock accordion duct. (NOTE: This is necessary to keep the stock duct from collapsing under full acceleration)
17 - Reinstall the duct on the air box lid using the stock clamp.
18 - Connect the duct to the throttle body with the plastic S pipe and 3" piece of red silicon pipe. (Yes, it goes over the superchargers drive shaft, and yes, you’ll have to squash it a bit to get it to fit right.)
19 - Use the 1/8" vacuum line supplied to reconnect the vapor canister to a vacuum source at the rear of the supercharger.
20 - Make sure you have removed the sealant from the vent on the front shaft of the supercharger. (there is a little tag there to remind you also)
21 - Close your hood and note where the top of the pulley makes a mark on the hood insulation. Cut this away with a hobby knife. Cut a section about 3" by 3"

TEST:

1 - Turn the adjustment on the boost-a-pump all the way to lean and then back toward rich by ¼ turn.
2 - Start the engine and IMMEDIATELY CHECK FOR LEAKS
3 - Test drive and then RECHECK ALL BOLTS AND RETENSION THE BELT, check the insulation under the hood for rubbing and trim as necessary.
4 - If you get knocking, adjust the boost-a-pump slightly toward the rich side. If you don’t, lean it out a bit. This will take a while to get right.

SERVICE:

Service the compressor with MOBILE 1 oil at 12,000 mile intervals. Add oil as required.
Check oil when you check your motor oil (every 3,000 miles is a good idea)
The supercharger only takes 6 ounces of oil (DON’T OVERFILL IT OR YOU’LL KILL IT)

To drain, Remove the upper 1/8" pipe plug, then the lower 1/8" pipe plug.
To fill, Replace the lower plug and add 6 ounces of oil then replace the upper plug.
There is a dipstick on the compressor. (It’s under the little black knob on the top)

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