X64v Posted February 14, 2007 Share Posted February 14, 2007 Just picked up a set of early 300zxt fuel injectors (anyone know the flow rating on them?) off ebay for cheap, and they won't fire. I've tried using a 9v battery, a 12v battery, and just plugging one right into the FI harness with the engine running. The guy says he ran them for a few days and that they were working when he sent them to me, but all six seem to be 'stuck'. Any ideas on what would freeze them up, or what could be broken? Or more importantly, how to get them firing again? It seems weird to me, because the injectors I'm running now sat for 10 years and are originals from an '82, but worked just fine the second I put 9 volts to them. Thanks. Quote Link to comment Share on other sites More sharing options...
eec564 Posted February 14, 2007 Share Posted February 14, 2007 Make sure the connectors are clean, and check the resistance with a good multi-meter. I forget if they're high or low-resistance, but they should register in either the 2-3 ohm or 8-16 ohm range. If they register 0 ohms or several (thousand) ohms or more, or no connection at all, you've been sold some bad ones. Quote Link to comment Share on other sites More sharing options...
getZ Posted February 14, 2007 Share Posted February 14, 2007 I had a set I ran laquer thinner though a while back and that seemed to have dried them up. I landed up putting them in a ultrasound bath of laquer thinner and that freed them up again. I used a ultrasound cleaner I borrowed from work, but I think you can get them from eastwood. This for a car that sits for long periods of time so I cycled a little wd-40 into the injector and put it all back together again. Quote Link to comment Share on other sites More sharing options...
X64v Posted February 14, 2007 Author Share Posted February 14, 2007 doh. I don't know why I didn't think to check the resistance first. But I just did, and they all landed right around 3 ohms, which is what they're supposed to be for low Z. I guess that would mean that they're all just stuck. Does anyone know a way to unstick them besides an ultrasound cleaner? I'm sure that would do the trick, but I don't have one or know anyone who does. Perhaps I should just send them out to be cleaned, since if they're stuck, they could be dirty as well? Would a good cleaning service make sure to unstick them first? Quote Link to comment Share on other sites More sharing options...
eec564 Posted February 14, 2007 Share Posted February 14, 2007 You could try removing the lower rubber o-rings and soaking the tips in gasoline. If there's crud in there, that may break some of it loose. Also, check the wires you were using to connect power to the injectors, see if you get 3 ohms through them when they're hooked up to an injector. Edit: Diesel may be a nicer choice to help clean things. It breaks up goo well also (Nissan specifies it for cleaning the hydraulic lifters on the P90a) and doesn't evaporate and stink to high hell (not to mention diesel doesn't tend to explode the same way). Quote Link to comment Share on other sites More sharing options...
X64v Posted February 16, 2007 Author Share Posted February 16, 2007 Ohm tested them (don't know why I didn't in the first place, just slipped my mind), got about 3 ohms on all of them. I just let them soak in diesel for a couple of hours. One of them unfroze, but I hooked it up to my air compressor at 35psi, and it's taking around a half second to close. What would cause that? Real gunked up maybe? Quote Link to comment Share on other sites More sharing options...
eec564 Posted February 16, 2007 Share Posted February 16, 2007 Man, they've gotta be gunked up bad. If you feel comfortable rebuilding them yourself, you could try that. Anyone have the exploded-view of those injectors? Quote Link to comment Share on other sites More sharing options...
X64v Posted February 16, 2007 Author Share Posted February 16, 2007 I probably wouldn't have a problem with that if I could figure out how they open. What about sending them out to be cleaned? Would that remove that much gunk? Quote Link to comment Share on other sites More sharing options...
eec564 Posted February 17, 2007 Share Posted February 17, 2007 Sending them out to be cleaned and flow-tested would be an excelent choice. It's just gonna be a lot more expensive than doing it yourself. All the coils appear to be good, and those are the only part of the injector I can think of that could actually burn out. You could either try popping them appart by yourself, and hoping for the best (I do stuff like that ALL the time) or you could call these guys: http://www.rceng.com/ Here's a fairly interesting page about fuel injectors that made it onto my bookmark list. It's not an answer for you, but interesting reading none the less. http://yarchive.net/car/injectors.html Quote Link to comment Share on other sites More sharing options...
X64v Posted February 17, 2007 Author Share Posted February 17, 2007 For $25/inj. I think I'll try to clean them myself. I can buy cleaned/flow tested ford injectors in any size I want for $25/inj. So how would I go about popping them open, without damaging them? And interesting reading for sure, thanks. Bookmarked. Quote Link to comment Share on other sites More sharing options...
eec564 Posted February 19, 2007 Share Posted February 19, 2007 I've never actually done it before, never had to. But I'd immagine you'd start by popping off the cap over the spot where the fuel comes out. I'd say patience is your friend and brute force is not. Just find seams where it could seperate and be gentle. Take off all the rubber seals first, then go for plastic. Make carefull note about where everything goes, and what direction it goes in. Something that looks like a flat washer might actually have a slight curve in it, and needs to go a certain direction. (Go ahead, just ask me about the master cylinder in a 64 XKE, brakes not fully dissengauging, and glowing discs.) If you have any injectors you know you won't be using and aren't important spares, you may want to try one of them first. However, since the ones you just bought aren't working at all, and if sending them back or having them professionally cleaned aren't options, you don't have anything to loose. BTW, this may seem obvious, but take off all rubber seals when cleaning injectors with solvent, rubber tends to swell up and leak when hit with chemicals it wasn't designed for. Maybe try and ultra-sonic bath. Quote Link to comment Share on other sites More sharing options...
X64v Posted February 19, 2007 Author Share Posted February 19, 2007 The junkyard had a half off sale this weekend, and while I was foreging around, I picked up a junk python injector off a zx to practice on. Well if there's a way to take it apart without damaging it, I couldn't figure it out. I eventually took a hammer to it, and it looks like the top is crimped on, and the bottom where the pintle cap is just doesn't come off. Perhaps the genuine nissan injectors actually come apart (I would think they'd have to to have the seals replaced) and you're right, I have nothing to loose, because I'm going to order some 338cc ford cfi injectors anyways if these are junk. Quote Link to comment Share on other sites More sharing options...
Clifton Posted February 23, 2007 Share Posted February 23, 2007 I've this place a few times. http://www.witchhunter.com/index.php4 Half the price of RC. I have also put used injectors is that were stuck. In my case, the car would barely but the fuel pressure and pulse width were enough to clear out the gummed up crud. Quote Link to comment Share on other sites More sharing options...
X64v Posted February 23, 2007 Author Share Posted February 23, 2007 Thanks for the link. If I need anything cleaned I'll probably send them there. I just ordered some rebuilt 338cc ford cfi injectors though so I'm good for now. Quote Link to comment Share on other sites More sharing options...
eec564 Posted February 23, 2007 Share Posted February 23, 2007 Clifton - Looks like a really good company, I've added it to my encyclopedia of links. X64v - Sorry you couldn't get those ebay ones working, let us know how the new ones turn out. Quote Link to comment Share on other sites More sharing options...
X64v Posted March 5, 2007 Author Share Posted March 5, 2007 Got the injectors a week ago. They're freakin sweet. All polished up, with the correct pintle caps and even a new set of seals. I'll definitely be using motor man for my injector needs in the future. Quote Link to comment Share on other sites More sharing options...
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