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First off, previous owner cut out the spare tire area in the hatch, so I have an unobstructed view of the top of the fuel tank.
I did notice an odd looking bolt/screw that was under some rubber mat on top of the fuel tank. I'm wondering if this bolt/screw is original or if it was put there because there may have been a pinhole leak that someone was trying to fix.The battery was sitting on the fuel tank without any support so it might have been bouncing around and damaged the tank, but I haven't been able to confirm that. .
Does this look normal to you?
I've also attached a photo of a new FD fuel tank for comparison. It's not high enough resolution to zoom into though.
Wow, that's a lot of no floor in the back of the car!
Hard to say if that bolt is original, probably the easiest way to tell is to simply remove the bolt. If it's in a fully threaded hole that doesn't go into the tank, it's from Mazda. If it's just screwed into the sheet metal of the tank and the hole goes through to the inside, it's a hack job.
If it is a hole and the rest of the tank is OK there are ways of repairing that, I'd do some googling around and looking it up. It's worth repairing if the rest of the tank is good.
Ummm..
I just recently installed my brand new fuel tank. (Search some of my posts, and I'll have some pictures to show.)
I don't recall seeing any bolts like that.
From the looks of your pictures, (maybe hard to tell), but it looks like something is seeping. Looks dark/damp.
I've never seen the hatch cut out like this before and left open. Looks awful. I'd want to repair that the best you can.
Looks like previous owner had a fuel cell in it. I also wouldn't love my battery sitting right over a tank like that.
That bolt doesn't look familiar, I just had lots of fun with my old and a new OE tank... But, FYI, the new ones are a bit different, for instance they don't have drain plugs.
[...], FYI, the new ones are a bit different, for instance they don't have drain plugs.
You know, I was feeling a little sad about that part when I got my new tank.
But what made me feel better was thinking: "I'll never have to drain or drop this tank for another 23 years!"
Drain plugs are REALLY nice to have though.
Your fuel tank is not OK. Let's see battery, hot muffler, and fuel tank bascally sitting inside the passenger compartment...
You're are rearended at a stop light and the three items comingle right behind the drivers seat....
Thanks guys - I removed the screw and it is clearly a hack of some sort. I guess I should drop the tank and get it addressed. I'm also planning to get a proper box for the battery. The previous owner did make a removable metal plate that separates the cabin from the outside that I removed for the sake of looking at the tank.
My goal is to have this as a streetable track car, and I'm thinking of going full cell given the above.
The major issue with the setup you just posted is you have fuel lines, pumps, and the tank all in the passenger compartment. This is a no-go.
You may be thinking: What's wrong with that?
Do you really want pressurised fuel inches from you with nothing in between you and it but air? Have you always dreamed of dying from being burned alive? This setup could do that for you. Any number of things could go wrong to cause this, poorly done AN fittings, faulty wiring or pumps, rear end collisions, bad potholes, or leaving the track backwards.
Never have the fuel system in the passenger compartment.
If you really want a fuel cell, you can just as easily (since your hatch floor is already gone) replace that with a flat plate and mount everything underneath. Most fuel cells are much smaller than the oe tank, and the space you gained losing the spare tire should give enough space to easily place all that other stuff underneath as well.
Thanks for the advice guys. I will close off the floor with some sheet metal. That said, if I separate the outside and inside, do you guys think having the battery at the far back of the car outs still a bad idea?
My car has the jdm rear seats, so no bins, and I would like too have the battery as low as the spare tire recess in the floor.
It never ceases to amaze me what some people will do to these (and other) cars when it comes to hacking them up.
The car the o.p. now has is a good example.
I remember how hard it was to find a decent FD back in '99 when I was looking, took me a year to find one that hadn't been used/abused/hacked.
Thanks for the advice guys. I will close off the floor with some sheet metal. That said, if I separate the outside and inside, do you guys think having the battery at the far back of the car outs still a bad idea?
My car has the jdm rear seats, so no bins, and I would like too have the battery as low as the spare tire recess in the floor.
Thoughts?
Having the battery in the back is pretty common, you could easily put the battery in a box below the floor with an access plate. If you use a Miata battery, it is vented so you could vent it under the car. The only difficult part is routing the battery cable to the front to the main fuse box.
Others who have put the battery in the rear could provide more insight on that process. I'll try to make a really bad mspaint version of what I'm thinking about tonight.
Having the battery in the back is pretty common, you could easily put the battery in a box below the floor with an access plate. If you use a Miata battery, it is vented so you could vent it under the car. The only difficult part is routing the battery cable to the front to the main fuse box.
Others who have put the battery in the rear could provide more insight on that process. I'll try to make a really bad mspaint version of what I'm thinking about tonight.
Vince
Thanks Vince. That is along the lines of what I was thinking of doing, but I might actually have the battery on the inside of the car to keep it protected from the elements and away from the fuel tank and exhaust. I'm planning to separate the battery from the outside with some sheet metal.
That said, from a pure safety standpoint, do you think there is a risk having the battery that close to the back of the car and near the fuel tank?
I realize most keep the battery closer to the center of the car in one if the bins. I don't have bins due to the rear seats.
Every time I see them, I have to say, I'm astonished at how many cars I see with fuel surge tanks, plumbing, and fuel pumps in the trunk. It's just not safe without a firewall, and I can't believe how common it is, whether there's a battery back there or not.
You have some problem, impact, etc and a 40+ psi fuel line comes loose in the interior, along with potentially a liter or more of fuel, and you could frankly be in deep ****.
I think a lot of this is from showcars that put all the fancy plumbing in the tank with a surge tank and whatever. I agree, I would not want to be in a car with a homemade bunch of hose connections holding back 40+ PSI of gasoline. Even best case scenario you'd probably get fuel smell from it.
I appreciate the concern and will keep the full system separated from the cabin by sheet metal. No need for more comments about the safety concerns related to in-cabin fuel system components.
That said, from a pure safety standpoint, do you think there is a risk having the battery all the way in the back of the car, but inside the cabin? Again, fuel components will not be in the cabin with the battery.
Battery needs to be a sealed battery to run in the cabin. Tons of threads on this with battery relocation. Just as long as it's securely mounted and sealed, you're good.
I'm planning to use a sealed battery and will put it in a box. That said, does it make a big difference, in your opinion, if the battery is closer to the front or rear of the hatch area?
At the end of the day it's just packaging - putting it where it will fit. It is a very heavy solid weight, in theory it's better to be closer to the center of the car and lower but I don't think it matters that much. Running a smaller, lighter battery is smart to begin with and I don't think even the best race car drivers would notice if the lightweight battery was installed in one place or another.
At the end of the day it's just packaging - putting it where it will fit.
Just a note for you Trivial Pursuit - RX-7 Edition players. The Japanese Thrid Gen RX-7 is perfectly corner balanced with an average Japanese male (171.4 cm, 67.6kg )sitting in the driver’s seat with the seat adjusted for his leg length. The battery was located where it is to achive that balance. Koby mentioned that factoid at one of the early Seven Stock Dinners he attended. That makes US cars a little lopsided with the average American male (176 cm, 88.6 kg) sitting on the wrong side!
