MGT Leaking Fuel tank Mod

[D3MON]

been helping out a few people in some FB groups i attend and thought i would post it here as well in case it may help someone.
fuel tanks for the MGTs are getting rarer and harder and harder to find, and sometimes leak from around the pressure nipple on the tank. this more started as just a temp fix, but just kept working and kind of forgot till recently that i had done it.
first start with pulling the pressure nipple slowly out.

from here you are going to remove the clunk system line.
(i honestly would recommend to replace the clunk system line while you are here, but it can be a PITA fishing it around, if you aren't going to, take care to not cut or poke the fuel line).
try to keep it accessible, i used the fuel tank primer nipple so it didnt fall into the tank.
then find an o-ring with a diameter close to the diameter of the narrower section of the nipple (above the flare).
note: this shouldn't see much fuel, so nitrile rubber may be ok to use here, but id recommend nitromethane and methanol resistant o-rings.

then from here use some sort of ARO or fuel to allow the nipple to slide in easier and re-insert it.

should look something like this.
it should pull the nipple flare up to more tightly seal around the inside of the grommet.

Hope that helps!
keep burning nitro.

 

[Losi215]

been helping out a few people in some FB groups i attend and thought i would post it here as well in case it may help someone.
fuel tanks for the MGTs are getting rarer and harder and harder to find, and sometimes leak from around the pressure nipple on the tank. this more started as just a temp fix, but just kept working and kind of forgot till recently that i had done it.
first start with pulling the pressure nipple slowly out.View attachment 125930
from here you are going to remove the clunk system line.
(i honestly would recommend to replace the clunk system line while you are here, but it can be a PITA fishing it around, if you aren't going to, take care to not cut or poke the fuel line).
try to keep it accessible, i used the fuel tank primer nipple so it didnt fall into the tank.
then find an o-ring with a diameter close to the diameter of the narrower section of the nipple (above the flare).
note: this shouldn't see much fuel, so nitrile rubber may be ok to use here, but id recommend nitromethane and methanol resistant o-rings.
View attachment 125935
then from here use some sort of ARO or fuel to allow the nipple to slide in easier and re-insert it.
View attachment 125936
should look something like this.
it should pull the nipple flare up to more tightly seal around the inside of the grommet.

Hope that helps!
keep burning nitro.

Your a beast with nitro. A true guru in the hobby. Bravo brother. Used to have an MGT as a teenager and just didn’t know how special it was or would become.

 

[D3MON]

Your a beast with nitro. A true guru in the hobby. Bravo brother. Used to have an MGT as a teenager and just didn’t know how special it was or would become.

thank you very much for the kind words
i dont really know if its just me being very partial to the MGT platform or what but it is just a great truck to own and run. really saddening to see them become so vintage and people being worried about running them for fear of parts. just a joy to run, i just hope this may be able to help others to keep theirs running and keep enjoying them.
hows the LST been going by the way? been able to get any more wheel time with it?

 

[olds97_lss]

I think I have one of those old tanks in a drawer somewhere. Tried fitting it on the side of a savage many years ago, but it was too wide and I didn't feel like doing the mid-tank mod, so I went back to running the 125cc buggy tank.

I do really like the MGT primer bulbs though. Gives me more time to get to them when they are on their roof and when ziptied/secured properly, they last a long time.

 

[Losi215]

thank you very much for the kind words
i dont really know if its just me being very partial to the MGT platform or what but it is just a great truck to own and run. really saddening to see them become so vintage and people being worried about running them for fear of parts. just a joy to run, i just hope this may be able to help others to keep theirs running and keep enjoying them.
hows the LST been going by the way? been able to get any more wheel time with it?

I actually ran about 3 tanks a couple weeks ago! It ran great all the way around. I will say I give up on trying to get the engine to idle for minutes at a time. I fixed the tank lid and think it’s sealing good, and the engine literally ran perfect over and over again. Drops right down to idle after full throttle, clean take off and crisp top end, but cuts out if I let it sit there for literally 20 seconds to put body on or something. With the lst2 mods, wheels and tires, and rc raven springs, it’s stiff as can be and I actually think it handled better with the old set up, worn out suspension, and old original tires lol drives really nice still though with no issues whatsoever. Still have to add my dynamite engine brace, high performance brake pads, new flywheel(will probably save that for when I absolutely need it one day, hopefully I won’t lol). I also sourced a brand new 170cc tank and might install it just to hopefully get a more stable idle. And no joke, I found a set of 4 brand new, sealed dynamite speed tread neutralizer wheels and tires for the lst2 for 40$ total including shipping. Don’t know why they were so cheap as the exact same wheels and tires are going for like 80$ to 100$ new for a set of 4. Anyway that’s what’s up with the LST. How’s your LST brother?

 

[D3MON]

I actually ran about 3 tanks a couple weeks ago! It ran great all the way around. I will say I give up on trying to get the engine to idle for minutes at a time. I fixed the tank lid and think it’s sealing good, and the engine literally ran perfect over and over again. Drops right down to idle after full throttle, clean take off and crisp top end, but cuts out if I let it sit there for literally 20 seconds to put body on or something. With the lst2 mods, wheels and tires, and rc raven springs, it’s stiff as can be and I actually think it handled better with the old set up, worn out suspension, and old original tires lol drives really nice still though with no issues whatsoever. Still have to add my dynamite engine brace, high performance brake pads, new flywheel(will probably save that for when I absolutely need it one day, hopefully I won’t lol). I also sourced a brand new 170cc tank and might install it just to hopefully get a more stable idle. And no joke, I found a set of 4 brand new, sealed dynamite speed tread neutralizer wheels and tires for the lst2 for 40$ total including shipping. Don’t know why they were so cheap as the exact same wheels and tires are going for like 80$ to 100$ new for a set of 4. Anyway that’s what’s up with the LST. How’s your LST brother?View attachment 125939

glad you were able to take it out for some running man! interesting on your findings in the handeling dept before and after the conversion. awesome you were able to source some of those parts! that is crazy the price you were able to get those tires/wheels for! i have been sort of keeping my eyes out for the future of when i will need to get some new ones but havent found anything that good of a deal lol.
i havent been able to really run it, got a few additions to the collection and have been getting familiar with them as i have time. but really haven't been able to do much at all sadly

 

[HannaI]

Figured I'd post in this thread since it's about the fuel tank. But you're right that it's pretty much impossible to find spare tanks. While setting up the fuel lines, I realized that the part that connects to the exhaust is broken. How essential is this part? Can I just maybe epoxy it back to the lid? Does the internal part connect to anything?

 

[D3MON]

if you cleaned it well, I'm sure you could glue it down, it is essential to have the exhaust connected to the tank, but the nipple itself that sticks down into the tank itself is not really needed. you could get a small nipple and thread it into the lid plastic, or even glue the nipple on top that connects to the exhaust line.

 

[olds97_lss]

If it were mine, I'd buy a nipple that has a nut and o-ring, or make a gasket for it. Anything you glue likely won't hold up to abuse/vibration.

Something like this mounted from the inside would probably work well:
https://www.amazon.com/Sullivan-Products-Aluminum-Fuel-Fitting/dp/B0006O8NTA

 

[D3MON]

If it were mine, I'd buy a nipple that has a nut and o-ring, or make a gasket for it. Anything you glue likely won't hold up to abuse/vibration.

Something like this mounted from the inside would probably work well:
https://www.amazon.com/Sullivan-Products-Aluminum-Fuel-Fitting/dp/B0006O8NTA

+1 to this, id definitely pursue this route to fix the tank. good find, didnt think of one of those.

 

[HannaI]

If it were mine, I'd buy a nipple that has a nut and o-ring, or make a gasket for it. Anything you glue likely won't hold up to abuse/vibration.

Something like this mounted from the inside would probably work well:
https://www.amazon.com/Sullivan-Products-Aluminum-Fuel-Fitting/dp/B0006O8NTA

Thanks for the tip! Just ordered one.