Cracked GasTank in S14, Need Help

[Alch]

First of all, if you own an S14 go check the passenger side of your gas tank, just to the left of the strap and near the horizontal seam. Chances are that you have a stress fracture forming that will pass perpendicularly through that seam.

To make a long story short, I woke up to the smell of gasoline all over my house. There was a crack going through the tank, and fuel was leaking all over my garage floor. So, I siphoned out the remaining amount of fuel in the tank as best I could and then started doing some reading. (Pictures below.)

It turns out this is a more common problem than one might expect, but the only thread I've found where people have actually documented the replacement was on a forum called "TampaRacing". Well, to remove the gas tank from an S14 you have drop the rear subframe and that's where I'm stuck at the moment.

How the hell do you unbolt the flange that joins the driveshaft to the differential?
There's not enough space between the diff and the flange to fit a socket wrench in there, it feels like a crescent wrench or box/open end wrench will strip the bolts, and even with the transmission in gear, there's still a bunch of play in the drive shaft making hammering on a wrench basically useless.

In the mean time I went and picked up another gas tank from a local guy parting out his 96 S14. It also shows the early warnings of a stress fracture forming in the same location. The current plan is to sand down/scuff up the plastic really well and see if I can get it coated in Line-X bedliner. A lot of adventure bike riders will spray their plastic gas tanks with this stuff and it appears to be pretty functional, and it should ad some rigidity or strength to the tank.

http://i42.tinypic.com/2uftwjs.jpg
http://i39.tinypic.com/eg974y.jpg
http://i41.tinypic.com/344yum0.jpg
http://i40.tinypic.com/10cqjva.jpg
http://i50.tinypic.com/73i7o9.jpg

Lastly, let me reiterate this: http://i49.tinypic.com/bfj3ap.gif If you own an S14 check your gas tank! http://i49.tinypic.com/bfj3ap.gif

[Alch]

Well, got the subframe and gas tank out. A word of advice: Even when you think you've drained all of the fuel from your tank, there's still at least 5 more gallons. Aaaand, I never want to do this again. No pictures of the gas tank, but imagine a big plastic thing with lots of rubber hoses molded to the shape of the S14's rear seats. Pictures:

Subframe out
http://i49.tinypic.com/5yb60m.jpg

Did a hover car swap/weight savings
http://i46.tinypic.com/14jtfzo.jpg

Only the struts remain
http://i46.tinypic.com/1z2gfms.jpg

And, a closer view of the subframe
http://i49.tinypic.com/2lixyja.jpg

[fliprayzin240sx]

Interesting, first time I've really heard of anybody having issues with their gas tank.

Car been in an accident before?

[HemiCharger]

Interesting, first time I've really heard of anybody having issues with their gas tank.

Car been in an accident before?


yeah I know that there is an overflow protection system on the s14 tank when you fill it up with too much fuel it will over flow through the breather tubes at the top of the tank and run down the sides. You can smell fuel then but I do not know how it could crack like that unless it was lowered or something hit the car?

[Alch]

I'm only aware of accidents as far as obvious damage from the previous owner. I don't think there was anything on the carfax when I bought the car five years ago.

The front bumper is still black ABS so he was in some accident requiring a new bumper, and the rear bumper's paint is a little cracked from backing into something, but not major accidents as far as I can tell.

However, my tank developed a crack at the location I mentioned, and then I picked up a tank from a guy parting out his 96 240sx and it was showing signs of forming a crack in the exact same location.

I'll be ordering a new tank on Monday. $500 :(

Edit: My car is entirely stock aside from 300zx brakes up front and braided lines at all four corners, and I've been in zero accidents.

[HemiCharger]

I'm only aware of accidents as far as obvious damage from the previous owner. I don't think there was anything on the carfax when I bought the car five years ago.

The front bumper is still black ABS so he was in some accident requiring a new bumper, and the rear bumper's paint is a little cracked from backing into something, but not major accidents as far as I can tell.

However, my tank developed a crack at the location I mentioned, and then I picked up a tank from a guy parting out his 96 240sx and it was showing signs of forming a crack in the exact same location.

I'll be ordering a new tank on Monday. $500 :(

Edit: My car is entirely stock aside from 300zx brakes up front and braided lines at all four corners, and I've been in zero accidents.


did it leak all the time? Was it only when the tank was at a certain level in other words were on the tank was the crack? up high or down low?

[Alch]

This was going on during finals week so I was having to rap up some projects and other stuff and I was getting home very late. I got home around 3 am Friday night/Saturday morning, ate a snack and about an hour later I started to smell, very slightly, some gasoline fumes. However, I had a cold so my nose was very congested. I woke up the next morning to the very distinct smell of gasoline throughout my house and found a big puddle of fuel under my car.

If you look at the pictures, the crack formed on the passenger side, to the left and parallel to the strap right near the pin. The crack also passed through the seam of the tank which runs parallel to the ground. I had to siphon out basically all of the fuel on the passenger side of the tank, before fuel stopped dripping on my floor. At the time the fuel gauge read about 1/2 of a tank, and I siphoned out ~4-5 gallons. Later, after the tank was out of the car, I emptied another five gallons which must have been sitting on the drive side of the tank.

I'm not sure how else to describe this. The crack was certainly low enough that this wasn't an issue that only occurred with a full tank. The tank basically has to be emptied before fuel stops leaking.

I do not know how long I had been leaking fuel since I'm usually parked on the street. However, I had not noticed unusually low gas mileage, my gauge was reading properly, and I did not smell fuel near my car in the previous times when I had been near my car. I should note that each day previous to discovering the leak, the car was parked for several hours in the same spot and I did not smell any fumes outside or inside the car.

To inspect your tank, jack up the rear end, and slide under the passenger side, infront of the rear wheel, and Look towards the rear of the car at the tank just to the left of the strap where the pin which holds the strap in place is located.

Long story short: I've reached the point where critical plastic parts are failing on me. About two months ago I had the top tank of my radiator develop a crack near the water inlet that connects to the thermostat housing. And now my gas tank has cracked. Since this is a pretty serious failure in regards to safety (fires can lead to serious injury, loss of life, property, etc.) I personally don't think this is something that should be overlooked. So, check your tanks. If you don't find anything, feel lucky. If you do, replace the damn thing before something much worse happens.

[Alch]

This isn't my tank, but that of a guy on Houston240sx.com who had the same crack form in his S14. He opted to try some ghetto plastic welding. Since I plan to sell my car in the near future after I finish my degree I wouldn't feel comfortable selling this to someone else with a questionable fix.

http://i48.tinypic.com/zivn0y.jpg

http://i45.tinypic.com/259wosi.jpg

[miravete]

well, now that you have your diff down, make sure the subframe bushings are good.

i took my sub down, and after i put it back up, the bushings gave.

so now im stuck with a "thud" sound when i shift.

[Alch]

Replacing the subframe bushings looks like such a huge pain in the ass. While I've considered it, I haven't notice anything "thuds" or stuff like that, and I plan to purchase something a little newer within a year. Out of curiosity what's the opinion on something like this: SPL Subframe Collars (http://splparts.com/store/product-info.php?pid19.html)

I would prefer not to dump more money into my car than I really need to. If I had a large disposable income, believe me, the first thing I would do is replace the open diff with an LSD along with upgrading the suspension.

Everything I've read about replacing the rear subframe bushings has led me to believe that it's something I really don't want to do.

I do know what you're talking about though after driving a friend's 280z that had blown bushings.

[Alch]

A quick update on what I've done.

I got in a new OEM gas tank from a local Austin Nissan dealership, and I got the parts guy to match Courtesy Nissan's price. So, $355 for a new tank. Unfortunately, in removing the tank we snapped the fuel vapor check valve into two pieces, and allegedly this isn't something that Nissan stocks in their Tennessee warehouse. So, that's now on a slow boat from Japan.

So, as I think I already mentioned. The front two bushings were tearing, and the back two looked to be in fairly good condition. I don't feel like I have the time or tools to try and cut out the old bushings and I knew there had to be another option. After recalling people filling their motor and tranny mounts with 3M Window-Weld (also known as Super Fast Urethane), I opted for that approach with my bushings. I simply filled in the two gaps on each bushing that should keep them from flexing as much, and hopefully prevent tearing. I also picked up the SPL Subframe Collars and while the urethane was still moldable I stamped the shape of the collar into it so that there would be a better fit. I look forward to the results.

Lastly, my stock exhaust was cracked after the second resonator so I ordered a new catback. Specifically, I got the Megan Type 2 Black because it was the closest to stock I could find. Unfortunately, it looks like the muffler is basically a straight pipe with a little bit of perforation. Hopefully it doesn't sound terrible. If this car had a KA-T it would be a non-issue.

Anyway, here are some photos:

Passenger side, front bushing:
http://i47.tinypic.com/x10riv.jpg
http://i47.tinypic.com/2n0u821.jpg

Driver side, front bushing:
http://i48.tinypic.com/2j48480.jpg
http://i47.tinypic.com/6895rq.jpg

Driver side, rear bushing:
http://i49.tinypic.com/x69go.jpg
http://i46.tinypic.com/2ue7amu.jpg

Passenger side, rear bushing:
http://i48.tinypic.com/ajp8af.jpg
http://i46.tinypic.com/2en1a9f.jpg

http://i46.tinypic.com/5loz68.jpg

http://i48.tinypic.com/30hv2og.jpg

[jamanrr]

The more I read about it the more it sounds like your car was lowered and or rode at a different height since the damage you have seen is cause from chassis rigidity of being lowered and hitting bone jarring bumps. That is what it sounds like such as cracked gas tank, cracked exhaust and bad bushings?

[Alch]

Unlikely. When I purchased the car I could swear it still had the factory dampers, and I replaced the struts with OEM equivalents. My car is at the stock ride height.

You have to remember that everything is 15 years old and has 165k miles. Rubber gets old and nasty. Regarding the exhaust, I'll take a photo of it later, but the crack was at the second, built in resonator in the factory exhaust system in the sheet metal just above a weld.

As far as the tank goes, I only know from what I've read online, but I've found several threads where people have had their tanks crack in the same point, and first hand there's the tank that I picked up from a guy with a '96 S14 with the same crack.

But who knows? I believe that I'm the third owner. The second owner was a guy who drove it during college and when I bought it from him it was entirely stock.

[DALAZ_68]

the exhaust you have isnt bad
its actually not loud, not on my CA anyway...

[SR240DET]

I had a crack in my s14 gas tank in the same location. Weird,..

[hOngsterr]

weird. my gas tank started to leak when i filled up my gas tank too o.o

[Alch]

I'm telling you guys. There's a design weakness in the S14 (after about 15 years). Check your tanks! If it turns out that yours is cracking or leaking you really should replace it. You should be to get a new tank for ~ $360. It's definitely not a fun repair.

I got my local dealership to beat Courtesy Nissan's price, and got a new tank for $355. Keep in mind that a new tank is only a tank in the parts catalog. You'll have to swap over everything else from your old tank or buy new parts. (Read: You'll need the gasket, cap, and screw top, along with the brackets for the fuel pump and fuel level sender, and then all of the hoses and clamps that run around the outside of the tank.)

If you do decide to replace it, drain as much fuel as you can out of the tank. It'll make it a lot lighter, and your garage also won't smell like gasoline for 3 weeks after you spill it all over the floor.

Just for reference, here's what the crack in my stock exhaust looked like. This is the second, built-in resonator, on the inlet side.

http://i45.tinypic.com/f3vn7m.jpg

[Alch]

Just for reference: your local autozone, advance, and oreilly are run by retards that are not aware that fuel hoses have different ratings depending on their use. Advance stocked the worst stuff: SAE 30R6 which isn't even rated to 50 PSI and definitely should not be used for a pressurized system. SAE 30R7 has a working pressure of 50 PSI and a burst pressure somewhere above that. Fuel injector hose (SAE 30R9) has a working pressure of somewhere around 100-150 PSI and a burst pressure well over that. SAE 30R10, according to Gates, can be fully submersed in gasoline and other fuels without suffering damage (it's also very expensive and hard to find).

I found the Gates 30R9 fuel injector hose at a local NAPA for $7/ft. The submersible 30R10 was $28/ft, special order, and came in pre-cut 1 ft lengths, so I couldn't replace my 15" long submersed fuel line. Fortunately, it appeared to be in great shape. So, I replaced all of the high pressure, 5/16" lines with SAE 30R9 and the low pressure 1/4" lines with SAE 30R7 and installed a new fuel filter. The remaining fuel that was sitting on the inlet side of my old filter was absolutely filthy. Of course it would be a lot of fun to replace everything with 30R9 and then know with confidence that if I wanted to do something stupid like fill the tank with E85 I wouldn't have to worry about my lines falling apart, but I'll leave that to the next owner of my car.

After installing the fuel pump and filter on the pump bracket I assembled and plumbed my new gas tank. Note that installing the fuel pump bracket and fuel level sender and bracket is significantly easier than removing them from a tank.

http://i46.tinypic.com/iglrer.jpg

http://i45.tinypic.com/10s7sdl.jpg
(Tape was removed before installing the tank)

Also, the FSM is absolutely terrible regarding showing how all of the lines are routed and what goes where. The closest thing to a half decent hose routing guide is the exploded view of the gas tank and fuel system on Courtesy Nissan's parts page. Keeping my original tank in the same condition that it was when I dropped helped alot with figuring out what goes where.

Following this we had several hours of swearing, busted knuckles and other hijinks related to trying to lift, align and then connect all of the proper hoses. The fuel filler neck and overflow or relief hose (whatever it's called) were the worst. No pictures of that, unfortunately since by that point I had become filth and didn't want to touch my camera.

Tomorrow we'll install the heatshield that goes between the driveshaft and tank, the rear subframe along with SPL collars, and new catback exhaust. Then bolt up the driveshaft, struts, and rear brake calipers and ebrake cables and I should be good to go.

We did test the pump by priming the system several times. The Walbro pump is much louder than the stock one, but I was happy to find no leaks, and hear the fuel running through the system.

[joeleo1]

I just had to replace the gas tank in my s14 as well. I hope I never have to do that again. Yeah I thought I had all the gas out too. Then dropped the tank and it was still a little heavy and had more gas.

[nathanong87]

i did it two weeks ago. not hard, just tedious. made a project out of it and did some subframe maintenance, while i was at it. i was also "lucky" to find a tank locally for 50$ picked up.

while swapping the tank, and installing the new one, i realized that my gas gauge was pegged at E....this is due to the floater. I then swapped the old floater over to the new tank it gas gauge works again!

[Mangudai]

Just for reference: your local autozone, advance, and oreilly are run by retards that are not aware that fuel hoses have different ratings depending on their use. Advance stocked the worst stuff: SAE 30R6 which isn't even rated to 50 PSI and definitely should not be used for a pressurized system. SAE 30R7 has a working pressure of 50 PSI and a burst pressure somewhere above that. Fuel injector hose (SAE 30R9) has a working pressure of somewhere around 100-150 PSI and a burst pressure well over that. SAE 30R10, according to Gates, can be fully submersed in gasoline and other fuels without suffering damage (it's also very expensive and hard to find).



Same thing happened to me. The guy swore up and down that hose he sold me was fine for a transmission cooler. The next day while I was driving it leaked fluid all over the god damn place. I definitely read what hoses says before using them now.