I am in the process of replaceing injectors. I have all the new injectors on the fuel rail, but dont know if I am to install the lower seal on the injectors or to the manifold? Please help since I have never done a job like this before.
Okay. Where are you now in this project? Are the screws removed and the fuel in and return hoses removed from the fuel rail? Is your battery disconnected? Are your water lines metal with rubber hoses or complete metal hoses? Well......(1) Remove the neg battery terminal. (2) Carefully with force use a long phillips to remove all screws from the injectors. (3) remove inlet and return fuel hoses from the rail. (4) Remove all 12mm bolts attaching fuel rail to cylinder head and to intake manifold. (5) Have a pair of needle nose plyers and a very thin flathead screwdriver to catch and pry outward the retaining pins holding each electrical connector to each injector. (6) Have a secure area...tray...to put these U shaped pins into , do not loose them. (7) Use phillips to remove or 10mm socket to remove all remaining screwnuts and small bolts holding the (a) cold start injector. (8) LABEL all electrical connector leads as they are removed immeadiately from each injector. If lost, then there are some factory lettering at each lead but the years make reading the numbers difficult at best. Scotch Tape and a magic Marker with white paper make a visible identification such as #3injector...#5injector...etc. (9) Pull your fuel rail out along with all injectors attached.... carefully...you do not want to destroy the plastic tip cups or loose any of the rubber O rings. These O rings prevent air leakage as well as some fuel leakage. The plastic tip cups prevent all fuel leakage.
The plastic tip cups are impossible to find ...so carefully inspect them... if any are cracked...well if cracked this must be repaired and not reinstalled until repaired.
Okay. Instalation: (1) On your work bench oreient your new injectors in the directions that (a) the screws will have them angled at the intake manifold and (b) in such a direction that your electrical connectors will be easy to reattach those U pins to with your needle nose plyers and small flathead driver. (2) Put small amounts of automotive grease at your large metal and large black plastic peices where they meet AWAY from the injector tips. This is only to keep the suckers from continually droping as you begin to angle them into their respective holes. Screw all that will screw iniatially to made them heldfast in place while you isolate the more difficult ones. #5 and #6 tend to be problematic if #1 and #2 screwed in first. If so then with your 10mm socket or long phillips screw down the fuel rail holdings to the intake manifold and don't forget to reattach your coldstart making certain you did not destroy its gasket when removal happened. Use a bit of grease to gently hold the gasket in place as you screw it down. Reattach hose to your fuel pressure regulator . Now #5 and #6 should go into their injector holes smoothly and if not then you will have to demonstrate patience as you gently continue to work all injectors downward and into their respective holes.
Okay. Reattach inlet and return fuel line hoses. Remount all 12mm bolts for the fuel rail. Put neg terminal back onto battery. Start your engine and check for leaks. It is best not to tighten your injector clamps untill all injector units are firmly in place....this will allow you to have your electrical connectors oreinented in a correct direction to reattach your lead connectors. Tighten all screw clamps and check everything. Now start engine and look for fuel leakage and listen for air leakage. And remember to use only SAE 9 fuel hose or fuel hose rated for high pressure fuel injection systems. Please do not use SAE 7 or carb fuel hose for your injector fuel hoses.
Well 82_280zx this is about it. At least you have a text visual of whats needed a bit more clearly. Not to suggest a mechanic here but most shops charge 200 to 400 dollars for what you are doing. Use your savings to take a loved one for a pleasant drive and dinner when finished. Have fun. Goodluck. shane-