To: email@example.com Subject: <280ZX> 83 ZXT F.I. hose replacement (LONG) Send reply to: firstname.lastname@example.org Date sent: Fri, 8 Nov 1996 12:55:53 Since there has just been discussion about changing FI hoses on the ZX model, here is my archived post/procedure: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Having just gone thru a two-evening process of replacing the hoses on my 83 ZXT fuel injectors - to AVOID replacing the injectors themselves - I offer the following LONG post for this list - and for the archives. My thanks to Mark Sayer for suggesting the alternative of doing the hoses alone, not the injectors. NOTE: THIS IS A LONG ITEM!! ************************************************** With thanks to Marc Sayer, her's one for the archives: How to replace the hoses connecting leaky fuel injectors to the fuel rail without replacing the injectors themselves. Mr. Marc opines that most of the time, it's the hoses leaking, not the injectors themselves. This is at least a four hour job the first time. More likely 6+ hours. Before you begin, make sure you have TWO FEET OF 90+ PSI RATED FUEL HOSE, INSIDE DIAMETER 5/16". This can be VERY hard to find, but DO NOT let anyone sell you standard 50 psi rated fuel hose. Your FI system can put out more than 50 psi, so this is not adequate. When you go looking for hose, NO one will know whatindaheck you're talking about. If you talk "fuel injector hose" to auto parts stores, they may be able to help. I found the hose at a NAPA parts store, $11 for two feet, NAPA part number H202. (YIKES!!) Marc recommends using the same stainless clamps Nissan used on the rail end of the hoses. This is fine, but they're $2.50 each and are hard to re-use, as they (1) tend to jam when re-tightening and (2) cannot open any wider to accommodate a larger hose then the original. If you buy a large OD hose, the factory clamps will NOT work. Get your clamps *before* you buy the hose and make sure they are compatible!! I ended up using six new Nissan clamps and six generic-type hose clamps. To begin: release pressure in the fuel lines by disconnecting the fuel pump while the car is idling. the connector is found under the back cargo pad, forward and slightly to the right of center. Your manual will show the location - but it's laying in the open and snaps apart. The car will idle for a few seconds, then die as fuel runs out. Disconnect everything in your way. This will include the large-hose PCV connection to the top center of the valve cover, and misc. vacuum lines. You will also need to disconnect your spark plug wires and get them out of the way. Be sure to number or otherwise ID the wires. You may find it most convenient to remove the cap and wires entirely just to get them out of the way. Here's a trick: to number plug wires at either end, use the plastic snap-on tabs which are used to close bread wrappers. Write a wire number on the tab with a fine-point permanent marker and snap over the plug wire. They can be re-used almost forever. This is real handy when doing ignition work requiring you to disconnect wires. (Thanks for the idea, dad!!) You will need to disconnect two fuel lines and one cooling line on the right front of the engine. The fuel hoses are hard to get off because they are the same material as the FI hoses, and very stiff. Be patient. One hose will leak gas and must be plugged with a spare bolt when disconnected..it's sneaky and may not leak at first, but it will eventually!! The cooling line will spout water and must also be plugged after being disconnected. There is one bolt on the right front corner of the engine which holds the fuel lines and coolant line in place; remove this. (When re-installing, put this bolt in before you re-attach the hoses; when attached to the lines, the hoses tend to pull the bracket holes out of alignment with the bolt hole and make it tough to re-install!) PROBLEM: you will find there is a stud on the top left corner of the engine's front which holds the fuel and cooling lines in place. It also holds the top of the PS belt tensioner in place. Here's the work sequence: 1) Using a 14mm socket, loosen the nut in the front of the PS *idler pulley*. This allows the pulley to move. 2) Using the tensioner bolt, slack the PS belt enough to remove it from the pulley. (Hey, now you know how to adjust the belt tension!! No extra charge...) 3) Remove the nut from the stud, and remove the lower left bolt which holds the tensioner to the block. Loosen the third tensioner bolt but do not remove it; this will allow enough slack to move the tensioner off the stud. 4) Find a second nut which will go onto the stud; lock the two nuts together firmly and use them to turn the stud out of the block. Now the lines are free. Remove the three bolts (two are small and easily visible, the third is a large bolt which doubles as an intake manifold bolt) which hold the fuel rail in place. Remove the three small bolts which hold the valve body (the round thingie with a vacuum line going to it) in place in the center of the fuel rail; you must be able to move it to get at the injector underneath. I found that I had to remove one (the upper and easier to reach) of the two fuel hoses attached to it, and was then able to move it enough to work underneath it. Now the rail SHOULD be loose enough to wiggle slightly. If not, look around and find out what I've forgotten - or what is different on your car. To disconnect the FI electrical connections can be tricky. I used a fine-point scratch awl on the very tips of the metal clips to push them out far enough that I could get a fine point under them and remove them by prying outward. In this process, I found it's almost impossible to avoid breaking off a tiny plastic retaining tab which holds the center-back of each clip in place. These plastic pieces get old and brittle, and I don't have a solution for this. I just pried carefully and made sure not to lose the metal clips. Once the clips are off, the connector pulls off easily. WARNING: these connectors are VERY brittle. Keep them out of your way while prying and working, because if you push against one, it will shatter and you'll be buying a replacement! The following procedure is offered because it's not what I did - and in retrospect, it would have been easier and maybe saved some of the stainless clamps for re-use. I took the clamps off, cut the metal hose-crimp rings, then cut the hoses and removed the fuel rail. I think the following will work better.... To get the old hoses off : 1) Loosen FI hose clamps and slide down toward injector. (If you don't have to open them up and remove them, they may work better on re-assembly. Your call.) 2) Using a very sharp knife or industrial-type razor blade, slit the hoses where they contact the fuel rail. You are NOT going to be able to pull this fuel rail off without doing this - the hoses are much too stiff and aggressive in their hold. Don't worry too much aboutscratching the fuel rail - it's hard enough that you would have to carve HARD to damage it. 3) Peel back the hoses and pull the fuel rail out of them. It won't go far because of things which restrict its movement, but you can get it loose. 4) Slide the stainless clamps off over the hose ends. 5) Using SHARP diagonal cutters, snip through the soft metal crimp rings which hold the bottom of the hoses in place. These are softer than is apparent, and cut fairly easily. If you keep working the cutters down further into the rings, you can cut them in half. 6) Remove the metal rings and using a sharp knife or razor blade, slice through the bottom half of the hoses where they go over the fuel injector inlets. NOTE: although the body of the injector is Bakelite, the inlets are metal! They have two aggressive barbs to hold the hose in place. Again, you don't have to baby them - you can keep cutting till they're off. You would REALLY have to hack on one before you would scratch it enough to cause any damage. 7) Remove the hoses. Then cut your new hose sections to length and slide them onto the FI inlets. A few drops of WD-40 inside the hose will help to lubricate the hose. You WILL have to push hard!! I used the butt end of a screwdriver to push on them until they were fully seated. When installing the clamps, think carefully about where to point the screws; consider what you'll have to work around if you need to tighten them AFTER you get the fuel rail back in place!! After hoses are in place, install bottom clamps; then slide the clamps for the hose tops over the hoses, lubricate inside-tops of hoses with WD-40 and press the fuel rail into the hoses. Use the clean marks on the rail for a reference on how far in to press. You will have to work back and forth to do this - those hoses are stiff enough that it takes some work to press the fuel rail into them. Tighten clamps, re-install bolts, etc. etc. No particular tricks goingback together except to re-install the stud on front of the engine and the bolt on the right front corner before re-connecting the fuel and cooling hoses on the right front corner. When all is secure, turn key on and let the fuel pump work; turn engine over for a couple of seconds; let fuel pump work again; repeat until it starts. The injectors will self-prime. Idle the car for a while; check for leaks. Clean up hands, etc. and take on a short drive, then check again for leaks. Final steps: Clean up tools Doctor cuts on hands Get cold beer outa refrigerator; ENJOY! ADDENDUM From: Marc Sayer Geeze that's expensive hose. :-( I can get the pushlock stuff for lots less than that. It is so common I thought you would have no problem finding it. Based on Al's dificulty and the price he had to pay for what he got, I will start selling the hose I use, as a convenience to folks. If folks want they can get it from me from now on, just ask for the 5/16" FI hose, and I will supply the right stuff. Its only $1.15/ft. Its rated at 250-300 psi. Also I have never had much trouble with the clamps, but I do keep every clamp I take off an FI car, so I have lots of them. Most of the time these clamps are reuseable. So it sounds like I need to start stockpiling these for folks too. The regular worm clamps work fine but I prefer the stock clamps, its not a big deal and I certainly wouldn't pay $2.50 for one, but they do look better and are easier on hoses. Anybody else out there have a stock pile of these little gems (or an FI car their parting out that they would be willing to scrounge them off of)?