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I'm going w/ the Spectra 3908, will prob. get it from Summit. Haven't had much time to cut the door yet, but when I do, maybe I'll post a pic. Happy Xmas to all.
i replaced mine a few months ago using the trap door, i was considering the Spectra and found too many complaints of them dying, and wasn't worth the trouble of taking them back to autozone & oreillys to get a replacement.
i replaced mine a few months ago using the trap door, i was considering the Spectra and found too many complaints of them dying, and wasn't worth the trouble of taking them back to autozone & oreillys to get a replacement.
That's odd--I read the same about the Delphis. The Spectra--the 3908, anyway (there are various model numbers that work on a 94 Z28, for some reason)--has good reviews, from what I've found. Did you replace the entire unit (pump & lsu)? Which one did you end up using?
Imma not too concerned about the rust thing. I suppose it could rust inside there if the tank isn't under pressure, but w/ the conditions mine has been in and what I can see, it seems unlikely. When I opened the tank for the first time recently, it was still under pressure, so there was little oxygen. I'll pump out a good bit of fuel thru a filter and see how it looks, but I don't expect to find anything.
A lift does make the process easier as you can stand and maneuver the tank, but I hardly consider is required. I have done both ways, and it sucks in either case. No matter what, you do have to remove the exhaust and the rear end to get enough angle to get the filler neck out.
Hell, Drew, I'm OLD. Geezers like me shouldn't be in small spaces tryin' to wrestle out gas tanks. That sounds way too much like...WORK! (When I feel the urge to work, I lay down until the urge passes...) I don't wanna pull it out AT ALL--not even using a lift. I'm very much in favor of the easiest method available.
You'll know when you crack the tank open. Mine sat for about 6 years with out ever having the cap opened, the entire tank was rusted on the fuel line and the fuel bucket was trashed. Not to mention the fuel sock disintegrated.
Hey folks, finally got around to this (just call me "Speedy"), and it went well. Cut the trap door, pulled the old pump/lsu assy, and checked the tank. There was a small bit of flecks, but I removed all the fuel (put it in my Jeep) to bone-dry, cleaned it out and used an old IT shop vac (much smaller than a normal shop vac) to remove any flecks, etc. Wiped my hand all around in there are it came out clean. Put in the new assy. (went w/ the Spectra), and as others have noted, the seal was too small. Checked the old seal under a magnifying glass and discovered it was in pretty good shape--still supple, no cracks or tears--so I put some rubber reconditioning balm on it and reused it. Got a good seal, and after a bit of work, made all the conections.
Went ahead and tried to start it--after ~6 years--and after a few tries, it fired. It was rough at first, understandably, but gradually smoothed out, and ran close to how I remembered. Unfortunately, the next day I tried again, and nada. Haven't checked it w/ a pressure gauge yet (will do so w/i the next few days--honest), but am reasonably certain it's the regulator. Need to get a fuel line disconnect tool, but it should go ok.
Re: the trap door, I fabricated a good seal all around, using some thick-density sponge stripping (available @ HD or Ace) and some 1.33" zinc. Riveted the stripping between the zinc and the door (used the longer Arrow rivets), then used sheet metal screws to tighten it down and expand the seal. To drill the holes, I first marked them thru the zinc by tapping a nail on the location, then put some scrap Hardie and zinc underneath & marked the drill bit to avoid going too deep & hitting the tank. I also painted all the edges, to protect against rust. To cut the door, I used my el-cheapo HF 3" cut-off wheel and 2 45-grit wheels, to minimize the gap. I also cut it a bit larger & over from the connections, which makes it easier to work on. It was a little more work, but eliminates any possibility of exhaust fumes, etc. getting into the interior. I actually spent more time working on the door than R&R of the assy, but if I ever need to swap out the pump, it'll be much easier.
It's true that pulling the tank is the 'correct' method, but all things considered, this was a good alternative. I'd just suggest taking the extra time w/ the door and the seal. It's worth it.
My car sat for around 10 years. I had plenty of stabilizer in it. It didn't have rust, but the fuel had turned into 'nuclear green jelly' crap. I did the trap door and replaced the entire in tank unit with a stock replacement. I think it was a Delphi. New filter, new pressure reg., new fuel and the car cranked. Didn't run long though- injectors clogged so bad it just quit running.
I built a stand with a cheap fuel pump, a bucket, some fittings, and a battery, so I could manually pulse the injectors under pressure and back flush them. I ran them through an ultrasonic cleaner multiple times, and replaced the screens and o-rings and after futzing with them for days got them all producing an acceptable spray pattern again. I'm gonna replace them (with what, I don't know) after I drive the car a while.
Basically, don't be surprised if your injectors give problems after sitting a long time.
His videos of testing various styles and brands of injectors are fascinating. He even has one of some Chinese rip-off injectors..
I suffer from the same problems. My car has been sitting for at least 8 years. The tank had a mix of 94 octane pump gas, and a VP Fuels blend for the 300-shot of nitrous consisting of highly leaded C16 (R+M/2 = >118) and Air Race (airplane fuel). No stabilizer. I'm tempted to cut the hatch, but 1) old age - mine - is an issue, and 2) the rear braces for my roll bar will require the agility of a contortionist to work through it. My preferred solution is to flatbed the car to the shop that did most of the work, and let them drop the tank, clean the injectors, etc., and go through the engine at the same time. Then sell it. But the COVID thing caused me to hold off. I might try selling it at a reduced price “as is”. Pretty sure someone could part it out for at least $10,000.
Right now it's in a snow bank where it's parked. I had a collector who claimed he was interested (he has something like 64 cars) so a buddy and I pushed it out of the garage and I cleaned the dust off it. Still looks like brand new, but I hate seeing it sit outside.
Hey Pioneer, was reading thru your thread the other day, and while it's terrible to say, felt better about my situation. But there are some key diffs: mine has always been in a (somewhat) climate controlled garage in FL, and was in exc. condition before it went down. The plugs/wires/etc. have < 6k on them, reg. sched. maint., no codes, and the day it went down, I was cruisin' easy @ ~110mph on I-75. My mistake was that while I had been starting it and letting it run, I hadn't been putting it in gear and forcing the trans fluid to circ. The seals dried out & blew under pressure. No excuse for inaction, but I was embroiled in a nasty lawsuit the HOA filed here (I eventually won), which took up my free time and $$. I'm not good enuff to rebuild a 4L60e and was planning to take it to a guy near here who does trannys for Nascar, but it ain't cheap. Still, I screwed up by letting it sit.
Another diff is I've kept mine stock. You could call the trap door a mod, but that's the only thing I've done. I'm considering headers and dual exh., but that's as far as I'll go. The only maint. I need is gear oil & coolant.
Fortunately, mine maintained fuel press. while it sat, so little oxy to promote tank rust; the bucket was pretty much pristine. When I siphoned the gas, I ran it thru cheesecloth, and there was very, very little debris. I ended up putting the gas in my Jeep; given the higher octane, the Jeep is running quite well.
Since getting back into it, I've replaced much of the fuel system back from the rail: relay, pump/lsu, filter. The FPR has gotta be crispy, not getting any fuel for ~6 years, and I was planning to replace it. Since I'll have the rail out, was planning to pull the injectors & check the O-rings. It ran well the other day when I tested the new pump (no hesitation, missing, etc.) and I've always used 92-93 octane, so they should be good. I might soak them in some injector cleaning fluid, but I'm hoping I don't need to send them out or (ack!) replace them. Power to the connectors is good, so after I put the rail back in, I'll see how it runs & if needed, test them in place. Guess I'll know soon enuff, but so far I've dodged some bullets.
Will let y'all know how it turns out. Good luck w/ yours; you've got more challenges, but keep at it. I'll be checking your thread.
I suffer from the same problems. My car has been sitting for at least 8 years. The tank had a mix of 94 octane pump gas, and a VP Fuels blend for the 300-shot of nitrous consisting of highly leaded C16 (R+M/2 = >118) and Air Race (airplane fuel). No stabilizer. I'm tempted to cut the hatch, but 1) old age - mine - is an issue, and 2) the rear braces for my roll bar will require the agility of a contortionist to work through it. My preferred solution is to flatbed the car to the shop that did most of the work, and let them drop the tank, clean the injectors, etc., and go through the engine at the same time. Then sell it. But the COVID thing caused me to hold off. I might try selling it at a reduced price “as is”. Pretty sure someone could part it out for at least $10,000.
Right now it's in a snow bank where it's parked. I had a collector who claimed he was interested (he has something like 64 cars) so a buddy and I pushed it out of the garage and I cleaned the dust off it. Still looks like brand new, but I hate seeing it sit outside.
I hear ya re: getting back there and cutting the door; I'm old, got a very bad back, and it wasn't easy (even w/o a roll bar) getting in a tolerable position to cut it. I had certain medical aids, w/o which I might not have tried it. I only wince when I think of how tough it would have been to pull the tank. Wise move to let someone else do it.
I ascribe various factors to dodgin' them bullets: a Z that's never been outta FL, a good garage, doing the reg. sched. maint. and keeping it stock all contributed. Still, it was dumb not to drive it when I coulda/shoulda; payin' for that trans rebuild will hurt a bit. Like you, I've had a couple of guys offer to buy it--when it was DOA--but I said 'nope.' Come back and see me when it's back on the road. But I suspect they wanted it cheap and to do the work themselves.
Injuneer, that brace would hamper things a bit in general, but it appears to be out of the way of the area needed to cut the trap door if you went that route. I do understand many folks don't like the idea of the trap door and I can respect that. Your car is in nice condition and you are thinking of selling, so it may make sense not to cut it. On the other hand, you've modded it with the braces, and are pretty far away from stock and a buyer may look at the trap door and easy access to the pump as a plus.
I drove my car to death before it was parked. My daily driver for MANY years. 251,000 miles, heads refreshed and Hotcam kit at 125,000. It's on its second transmission, 3rd clutch kit, 3rd water pump, 2nd opti, 3rd alternator. It's a basket case, but of all my toys it holds a special place for me. I let it go to pot and parked it for more sensible transportation when kids were born and we upsized into a bigger house. Now it's going to be a project for me and my son who is 14 now.
I studied things pretty hard before I did the trap door. Structural, safety, etc. But there was just no way I was going to actually pull the tank in my driveway and go through all of that not even knowing if I still 'had an engine' after sitting in the elements that long. After wrenching on a few imports that HAD a trap door from the factory, it made the concept much more palatable.
Odd thing.... the “collector” who was interested last year texted me today, and said he wants to make an offer tomorrow. He's done this twice before, but didn’t follow through. Maybe third time is the charm.
I have no issues with cutting a hatch. I've offered guidelines in the “sticky” thread - round “corners”, secure seal and lots of sheet metal screws to keep fuel out of the interior in a crash/roll over. If I did it, it would be done with the same OCD engineering approach as everything else I have done to the car. Would not be a negative to the right buyer. Definitely an asset.
But I realize it’s time to move on. I don’t think it’s realistic to figure that I can take it to the track. I live a few miles from “Englishtown” (Old Bridge Raceway Park) drag strip, and used to drive my car or trailer it there. But they closed the drag strip and they're leasing it to Coparts to store their “flood” recovery cars. Two other strips in NJ, but they would require trailering it and I no longer have my trailer or the Silverado tow vehicle.
The other downsides are age and money. I retired 5 years ago at xx. I'm still doing consulting work, but 2020 was a bust because of COVID. I'm fortunate to be in good physical shape for my age, so that's not an issue. Saved for retirement, but the cost of living in NJ is ridiculous. We live in a small (1,700 SF) 3-bedroom ranch, and property taxes are approaching $12,000 per year. Then there's the cost of auto insurance in NJ, sales tax, income tax, increasing gasoline tax, etc. Selling the Formula will reduce the auto insurance, and we can use the money for a nice vacation, or a luxury item while we can still enjoy it.
keeping my fingers crossed for tomorrow.
Last edited by Injuneer; Feb 22, 2021 at 10:42 AM.
Injuneer, It sure looks like a super-nice car that was done right. Maybe the deal will go down with no hitches!
Tampaguy, you are correct, my car has been 'rode hard and put up wet' so to speak. I maintained it reasonably well when a daily driver, but I wore it slap out. I thought I was done with it, but I looked at it sitting in the yard last year in the midst of the Pandemic and it just called to me. I'd be money ahead to seek out a lower mile LS1 car, but I can better-afford to slowly refurb this one than try to come up with money to get into something else. It's more of a hard-headed thing for me at this point to see if I can get the ol' girl running reasonably well again.
Last edited by Pioneer1; Feb 21, 2021 at 07:54 PM.
I'm not exactly in love w/ living in FL, but at least the costs are reasonable. I grouse about insurance costs, but comparatively, they're not nearly as bad as other places--like NJ or NY. Actually, Geico recently started a 'classic car/boat' line--mostly for vehicles that aren't DDs & are driven sporadically--so the insurance on the Z should drop down somewhat. I'm not looking to sell it; it's a good freeway cruiser, and there's lots of long, flat, straight freeway runs down here. I-95 is like a rally road, and they don't seem to patrol it much. W/ a good multiband detector...
Pioneer, not sure what the ultimate plan is for yours, but given the issues w/ your wiring, less-than-ideal conditions and erratic readings, if you plan to keep it, I'd be thinking 'bout replacing the wiring/harnesses. It ain't exactly cheap, but will address a known issue and help narrow down elec. issues--or at least rule out wiring as a source. Check out this link:
They have all the wiring configs, including the chassis wiring harness, and their prices are typically less than other sites--and much less than local outlets. For ex., I went looking for the FPR the other day, and locally, they want $65-$100 (way high, IMO); CarParts has them for somewhat less. True, there are diffs in manufacturers, but still... I've bought lots of stuff from them--mostly for my Jeep--and it has all worked out. Got a bad Dorman window regulator from them once, they sent me a replacement right off, no problem. (Disclaimer: CarParts pays me nothing for this psuedo-endorsement.)
