WARNING: Use Teflon tape or sealant only where indicated. Do not use oil on threads.
WARNING: This gauge is supplied with a special restrictor fitting that Must be installed on the braided line leading to the nitrous gauge.
WARNING: USE ONLY -4AN high pressure stainless steel braided line when installing this gauge. All fittings must have a minimum working pressure of 2000 psi.
1. If you are not familiar with nitrous oxide systems and their installations do not install this gauge. Have a qualified mechanic install it for you.
2. Determine where the nitrous gauge will be mounted and the source of the pressure (bottle outlet or nitrous solenoid inlet fitting). Then determine the length of steel braided line required. (Auto Meter offers three -4AN stainless steel braided line kits: Model #3227- 3 feet, Model #3228- 6 feet, Model #3229- 4 feet)
3. Secure the -4AN stainless steel braided line to the back of the gauge as shown in the illustration.
4. Install gauge in appropriately sized dashboard hole or use under dash panels. Secure gauge with the mounting bracket provided. NOTE: If alternate gauge mounting is used other than in-dash or under dash, mounting provisions may have to be determined by the installer.
5. Make sure the nitrous bottle valve is closed.
6. Secure an in-line gauge adapter (eg. NOS part #16770 or #16771) in a vice. Install the special restrictor fitting (supplied with gauge) in the in-line gauge adapter. Do not over tighten as this may result in stripped threads or a broken fitting.
7. Remove the main nitrous feed line from the bottle or the nitrous solenoid. Install the in-line gauge adapter with the special restrictor fitting either on the nitrous bottle or nitrous solenoid. Re-install the main nitrous feed line. Install the braided line from the nitrous gauge to the restrictor fitting.
8. Open the nitrous bottle valve.
NOTE: Test all fittings and hoses for any leakage. If any leaks are detected, determine the cause of the leak and repair. Do not operate vehicle if any leaks are detected.
Fuel Pressure Gauges (w/o Isolator)
WARNING: If pressure gauge is used in a fuel application, the gauge must be mounted outside of the vehicle. This will prevent the possibility of a gas fume explosion in the vehicle interior.
IMPORTANT: Both the 0-15 and 0-100 PSI Fuel Pressure Gauges must be mounted outside the vehicle unless an Auto Meter Fuel Gauge Isolator is used in conjunction with the Gauge. This is required to prevent the possibility of fire or explosion in the vehicle’s interior.
To Mount Inside of Vehicle:
0-15 PSI, 0-100 PSI: Must use full sweep electric model, or mechanical gauge with Auto Meter Fuel Pressure Isolator. See catalog or visit www.autometer.com for more information.
To Mount Outside of Vehicle:
Note: Only Auto Meter Liquid Filled and Ultra-Nite Gauges are water resistant! User should take appropriate precautions to protect all other Auto Meter instruments from getting wet. Failure to protect your gauges from water sources can result in inaccurate gauge readings or complete failure of the product. Instruments that have sustained water damage are not covered under warranty.
1. Determine best location for mounting the Fuel Pressure gauge outside of the vehicle. Mounting cup kit 5201 or 5202 is recommended for mounting gauges on vehicle’s cowling in front of windshield. Drill necessary hole and install rubber grommet where pressure line passes through sheet metal.
2. -4AN braided stainless steel tubing is recommended because of the highly flammable nature of racing fuel. Use Auto Meter kit 3227 or 3228. DO NOT USE NYLON OR COPPER TUBING WITH COMPRESSION FITTINGS.
3. Route pressure line through grommet to engine compartment, keeping line free from hot engine components or moving parts. Plumb line into vehicle’s fuel line. Be sure to use teflon sealing tape on all tapered threads for a good seal.
4. Start engine and thoroughly check for any leaks.
5. Connect WHITE light wire to dash lighting circuit or to other 12V source. Connect BLACK light wire to an engine ground.
Fuel Pressure Gauges (w/ Isolator)
NOTE: Fluid leaking from system will cause gauge to read incorrectly. If leakage occurs, fill isolator with solution of half water, half propylene glycol (antifreeze). Repeat Step 4.
NOTE: Use thread sealant on all pipe threads to insure a leak free seal.
1. Install gauge and tubing assembly in an in-dash hole that is 21⁄16" in diameter for 21⁄16" models and 25⁄8" diameter for 25⁄8" models. Gauge may also be mounted in Auto Meter Accessory underdash panels. Securely mount gauge using mounting bracket provided. If mounting gauge is somewhere other than in-dash or underdash, you may be required to fabricate necessary provision.
2. Isolator must be mounted in engine compartment. (DO NOT mount on firewall per NHRA/IHRA rules.) Drill two 17⁄64" dia. holes in desired location. Mount isolator mounting bracket using the bolts, lockwashers, and nuts provided. Gauge and isolator should be mounted at the same height to insure accurate readings. If not mounted level with each other, the fluid weight will cause a slight accuracy error.
3. Drill a 7⁄8" dia. hole in firewall in line with center of mounting bracket. Route the braided tubing through hole into engine compartment.
4. With filled portion of isolator in upright position, remove dust plug. Pull braided tubing through center of isolator bracket and hold end in upright position. Remove dust plug and quickly thread braided tubing into isolator port (be careful not to spill any fluid).
5. Secure fuel pressure isolator to mounting bracket using the lockwashers and nuts provided.
6. Slit rubber grommet provided and position in firewall hole so braided tubing holds firmly in place.
7. Determine most desirable location (in line between fuel pump and carburetor) to plumb into fuel system. Thread necessary adaptor fittings into fuel side of isolator.
8. Tee isolator into vehicle’s fuel system. We highly recommend that Auto Meter braided stainless steel tubing (Models 3227, 3228, or 3229) be used for this application.
9. With engine running, check to make sure gauge pointer moves in a smooth manner and reads the correct idling pressure.
10. Connect white light wire to dash lighting circuit or other 12V source.
11. Connect black wire to good engine ground.