2.5 Broken Gas Tanks

[HumboldtBlazer]

Well I'm sure I'm not the only one that has had a problem with breaking this tank. I am on tank 6 (not the break in process but broken tanks). My tank always breakes in the same exact spot. It break in the back outside bottom corner the part of the fuel tank where the nipple for the hose that goes to the carb.

I though that when I installed my aluminum chasis braces that this would stiffin my chasis enough so I would not be twisting the chasis and causing it to break. Now I beleive that the main problem is that there are 4 screws going into the tank and the standoff posts are moulded into the tank itself.

On my buggy, stadium truck, and on-road car all gas tanks are the same. There are installed onto the chasis with 2 seperate posts and 2 screws to hold the posts. This makes sense to me because when the chasis flexes the gas tank can flex also. My question is why did Traxxas think this was not a good idea and decided to screw it down with 4 screws not allowing for flex? Has anyone been havin this problem along with me?

I got tired of paying $15 everytime I wanted to jump my Maxx more than 2 feet off the ground. Heres what I did and my gas tank seems to be finally holding up. I used two p4 o-rings (any o-rings that are the right size will work) and placed them on the front inner post and the back outer post and wedged them in between the chasis and where the screw goes into the tank. I only screwed 2 screws in total not 4 and put the screws where I placed the o-rings. So now the o-rings act as a shock absorber where the tank is actually screwed into the chasis.

I took it out Saturday and jumped the poop out of it. No broken tank. I jumped huge so I am sure I did enough to test it to see if it would last and feel confident in it. Sorry to write you all a novel but I hopes this helps anyones breaking tanks. :beer:

 

[Rob D]

I havent broake a tank yet i do have a old style maxx though but if i do ill rember this

 

[x_789]

There was a big thread about this a few weeks ago do a search lots of good info...x

 

[FastEddy]

I beat the living padoodles out of my Maxx. I'm on my 3rd one and have never broken a tank.

 

[RaCinJason399]

Maby you can take a broken one and take the flastic and glue it or melt it to a new one where it breaks... make the tank stronger.. just a idea...

 

[maxxtrac]

Maybe you are screwing the tank down to tight

 

[SkyMaxx]

Sounds like a decent solution. The tank breaking is a problem that is common to all Maxxes new and old.

I swore up and down that I wouldn't see this problem, until one day I found one of the posts pushed into the fuel tank. Not a happy camper.

Anyway, my solution was much like yours only I used fuel tubing.

Originally posted by SkyMaxx in another thread
Post #9
quote

Here's my solution to the problem.

What you will need:
A four inch length of fuel tubing.
Four mounting screws that are 1/8 longer than the stock mounting screws.

The procedure:
1. Remove fuel from tank
2. Remove tank from chassis
3. Cut four 1/2-3/4 inch lengths of fuel tubing from your 4 inch piece
4. Force as much of the tubing onto the individual tank posts, leaving about 1/4 inch beyond the end of the post
5. Position the tank over the holes on the chassis.
6. Using the longer mounting screws, feed the screw through the chassis, into the fuel tubing and then the mounting posts.
7. Tighten the mounting screws until you compress the excess fuel tubing about 1/8"
8. Re-attach the fuel lines, fill 'er up and go.

This will give you some motion on the tank, but the fuel tubing will act as a shock absorber. I did this mod after I cracked my fuel tank (about eight months ago), and I have not cracked the replacement (despite several bash sessions with Pirata, The Master of Disaster.)

These directions should get the job done. If you are having trouble visualizing the mod, let me know, and I will snap a photo of my tank and post it for you.

Good luck and happy Maxxing!

I have had no problems since, and I abuse my T-Maxx.

 

[massivex]

Great stuff there. I snapped my tank EXACTLY the way you described. I only slacked off my screws. It worked so far, and after my last wreck thats saying something. You took it one step further.

The fuel tube sounds like a good fix too. I've only cracked one tank yet (into a curb). Heres to hoping I don't ever crack another.

 

[John Clark]

Cracked my first tank in 2 places (around the posts) when i dead-ended a big big rock (I also broke the stock motor mount, and cracked a front drive shaft yoke). Trust me, gluing, sealing and melting these things does no good, unless you can do it from the inside, since they're pressurized. You can only slow the leak down.

I used Skymax's fix on my new tank, and it has worked perfectly so far. Thanks Skymax, you're a peach LOL.

 

[SkyMaxx]

No problem. Always happy to help. Did you use the original screws or go with something longer for the tank mounting? Just curious and trying to fine tune the directions. I used the original screws but others have had to use slightly longer ones.

 

[John Clark]

I used the original screws also. Instead of trying to cut the tubing to the proper length beforehand, I put a longer piece on than I needed, and then trimmed it to length. With some posts being taller than others, you can get a uniform overhang this way. 1/8th inch below the bottom of the post still left lots of meat for the screws to bite, and still clear the EZ-start.

Anyone who hasn't done anything with their tank yet, believe me, this is a much better method than trying to fit something between the tank and the chassis. I tried that the first time with small slivers of fuel tubing, and got so frustrated trying to line everything up, I was ready to light a match to the thing.

 

[HumboldtBlazer]

I just used tweezers to hold my O-rings in place. Tweezers with a rubber band are my extra set of hands.

 

[SkyMaxx]

I finally found a way to break a fuel tank, even with my mod. It has taken me about a year to do it, but here it is.

Take off from a really huge height and land really hard on your lid.

I didn't do this with the intention of destroying anything on my T; but this past weekend while bashing with Pirata, I managed such a feat. Landed from about ten feet up and ended up cracking the tank near two of the support legs. The tank was still in one piece and since the cracks were on the bottom, no air leakage. It made for dirty running as the fuel was slowly leaking out, but it still ran. Ten minutes after I ran out of fuel, I slapped a new tank on with my mod and continued to run...just made a little better effort to land on my feet vice my lid.

Just goes to show you that no mod is perfect.