SR 86 fuel problems

[adam_loves_hachi_roku]

hey guys
(
first time ive used this forum so be gentle)

my car is SR20DET t28 ball bearing in my ADM 86...

problem: when fuel cap is on the fuel tank pressurizes and spurts leaks form various points

tried: a charcoal canister, fuel just started leaking form the bottom...

comments: it runs fine without the charcoal canister and with the fuel cap off but we all know this isnt too practical...especially for skids...(right hand corners only )

Some thoughts: its still got the ADM tank and thinking needs to be changed to JDM/EFI tank

would be awesome if you guys could help out.

thanks heaps

[Skylar]

Where is your breather?

That prevents fuel tank pressurising or something and the charcoal can. catches stray air-borne hydrocarbons or whatever from entering the atmosphere for it to be sucked into the engine when it runs?

How are your fuel lines set up? One feed/one return/one breather right?

[adam_loves_hachi_roku]

umm well i didnt do the conversion and havent had a proper look but i know there is one feed and a returnm but i dont know if theres a breather...there was a fuel line in the engine bay that was going to no where and first time i drove it after 5 minutes it started pissing out fuel...if i was to put a breather on do you think that would solve the problem?cos it sounds like the answer but if theres not one already a breather i would assume the guys who did my car are retards?

[Skylar]

Yep, assume everyone is a retard until proven otherwise.

Go to the fuel tank end and make sure the breather is connected at that end. If the breather isn't connected to anything on the engine bay side, it should breathe through there. and have fuel fumes in your engine bay. AWESOME! Hook it back up to charcoal canister.

[fantapants]

he has hooked it up and the tank still pressurises and pisses fuel out the canister? or did i miss something? you need to stop the tank pressurizing. if you have a surge tank im guessing something has been plumbed wrong a that end.

[Skylar]

How much fuel is in the tank?

[adam_loves_hachi_roku]

thanks for the help guys...

its got a good amount of fuel in but couldnt tell you really cos fuel gauge isnt working atm gotta get auto elec to look at fuel gauge and speedo...

ill have a good look see if everything is connected and if i can get the problem fixed if not i might get back to yous...but thanks again guys

[ke70dave]

ahh yer i had this problem when i first did my 4age conversion.

basically the breather line has been connected to a connection on the tank that is submerged in fuel. and the fuel tank presurises under normal conditions (temp change or evaporation of fuel) and it forces the fuel out the breather line or any other lines it can find.

there are 3 pipes going into the tank. 2 are quite long and go to the bottom or close to, the other one is cut short.

you want the feed for your surge tank/engine to be the closest pipe to the bottom, the return to be the next closest one, and you want the breather to your charcoal canistor to be the shortest pipe, so that it remains out of the fuel when the tank is full. so it can release air, not fuel.

now unfortunately the best way to do this is to take out the pipes out of the tank and make sure which pipe is what. unforunately you have to take the tank out to this. not a big job just a bit of a pain.

im not sure if ke70 fuel tank is the same as ae86, but if you look at my tech article on the surge tank (tech articles of this site) then you can see a picture i took of the pipes and the connection. but yer your best bet pulling yours out so you know exactly what your looking at! and when you figure it out, post up some pics for others to see!

[FAST EDDIE]

not sure if you want to use a charcoal canister but if u get stuck i use moto fuel tank, in only, breathers. tank shouldnt leak uner pressure anyway!!!