Tech Tips

1. HESMIL Diagnostic Codes
2. CARB EO NUMBER LINK
3. Try our bulletin board
4. Fuel Pump / Regulator installation
5. JK Super Charger Instructions
6. MPI kit installation tips
7. Instructions for using the HESEZCAM tool
8. Fuel Pressure Regulator Eliminator Plug
9. Water pump torque specs
10. Jeep 2.5 & 4.0L Throttle Body Spacers
11. Push Rod Lengths

1. CARB EO NUMBER LINK
   

   Below is the link to the California Air Resourses board where the CARB number is located for the Mopar MPI Conversion Kit. Some people are still being questioned as to the legality of the kit and hopefully the link will help you with your smog testing people. Once at the page type in the CARB EO# D-265-21.

   http://www.arb.ca.gov/msprog/aftermkt/devices/amquery.php

    

    

2. HESMIL Diagnostic Codes
   
   CLICK HERE to download the check engine "MIL" diagnostic codes.

3. JK Super Charger Instructions
   

   These are the instructions for the JK Super Charger kit. This the latest version and are subject to change.

    http://www.contentedits.com/img.asp?id=23693

    

4. MPI kit installation tips
   

   Download MPI Kit instructions and Installation tips.

   https://www.contentedits.com/img.asp?id=35892

   
   

    

5. Instructions for using the HESEZCAM tool
   Click here to download the HESEZCAM instructions directly from the products page.

6. Try our bulletin board
   
   If you have an issue or need help with a subject not found here, try visiting our bulletin board to view previous discussions or to post a question.

7. Fuel Pump / Regulator installation
   CLICK HERE to download installation instructions.

8. Fuel Pressure Regulator Eliminator Plug
   

   The fuel pressure regulator plug is designed to be used with our rear mounted fuel regulator / fuel pump kit (Part # HESRMFPR1) where the stock regulator is eliminated from the fuel rail.
   CAUTION: DO NOT PERFORM THIS PROCEDURE ON A HOT ENGINE!
   Relieve the fuel pressure from the rail using a fuel pressure gauge with a bleed off valve or other suitable tool. Use caution as the fuel is under high pressure and the appropriate safety precautions should be taken. (ie: safety glasses etc.)
   Remove the fuel pressure regulator hold down clamp from the fuel rail. With a twisting motion remove the fuel pressure regulator, being cautious to make sure the old o-rings are also removed.Install the new o-rings into the fuel rail. This is simple as they will only seat in their respective grooves.
   Spray the o-rings with a silicone based or similar type lubricant to help ease the installation of the plug into the rail. With a twisting motion seat the plug into the fuel rail.
   Install the hold down clamp.
   Cycle the ignition switch to pressurize the fuel rail and check for leaks.
   You may either remove the stock fuel return line from the rail and cap the nipple or simply leave it attached.

9. Water pump torque specs
   

   For vehicle years 1997 and earlier, use 22.0 foot lbs. of torque. For all vehicles 1998 and later, use 17.0 foot pounds of torque.

10. Jeep 2.5 & 4.0L Throttle Body Spacers
    

    Remove the four bolts retaining the throttle body to the intake manifold. Remove and discard the throttle body gasket. Install the spacer (HESCO logo right side up) and gaskets, installing one gasket between the manifold and spacer and one between the throttle body and the spacer. Use the (4) 55mm cap screws and (4) washers to install the throttle body. Torque the bolts to 10-12 inch pounds. Remove the bolts retaining the throttle cable bracket to the manifold. Some Jeeps have two while earlier models will have three bolts. Place the black spacers beneath the bracket and install the 50mm bolts and flat washers. These also torque to 10-12 inch pounds. Dyno testing showed an 11 hp. Gain with an open air filter system. The typical power range differs with engine configuration.

11. Push Rod Lengths
    

    Jeep Push Rod Lengths

    Length Part Number Engine Year

    9.639 PR-437 4.0L 1987-96

    9.728 PR-399 4.2L 1989-90

    9.700 PR-353 4.2L 1983-88

    9.622 PR-333 4.2L 1977-80

    9.594 PR-301 4.2L 1972-76 Stamped Rocker

    9.656 PR-332 4.2L 1971-74 Cast Rocker

    Custom Length Push Rods

    9.500 PR-310 Used with the aluminum head on decked engines.

    9.547 PR-327 Used with the aluminum head on stock engines.

    9.560 PR-310A

    9.668 PR-303

    Most of these push rods can be found on the web site in the "Valve Train" section.

    If you believe you need a length that is not listed call and we will be happy to try and

    accommodate your needs. You may also need a set of rocker arm shims to achieve

    the proper lifter pre-load even with a shorter push rod. The part number is

    HESRASK and can also be located in the "Valve Train" section.