rxmadness

iTrader: (1)

my gas gauge doesnt work in my 84.....sending unit??

mazdaverx713b

iTrader: (91)

check the wiring for the sending unit at the sender. make sure its not broken or corroded. check the connector for the same. if that checks ok, you can drop the tank and pull the sender and test it. i have a writeup on dropping the tank if you're interested. straight from the 84 FSM:

rxmadness

iTrader: (1)

thats great help man!! thank you, also before i dig into it since im very new to rx7's can you get at the top of the tank from inside the car?? and i would love to see the write up if you have time, i would like to read it and learn incase it comes to me dropping the tanks
thanks

mazdaverx713b

iTrader: (91)

the sender can be accessed from the left side of the tank. the lefr rear wheel must be removed and you will have to remove teh splash guard in order to access it. you will need to drop the tank in order to do any kind of repair work to it though. i'll get that writeup for you.

mazdaverx713b

iTrader: (91)

i'll start with this bit of info and then add the pics.

dropping the tank is no big feat. just make sure you drain all of the gas first. it makes a big difference when removing and reinstalling the tank. pop open te filler door and remove teh three 8mm bolts holding the filler neck on. push the filler neck through the opening. it may be a little tough at first but the seal will unstick and it will push through.

next, get under the car and remove the three lines ahead of the fuel tank. eaiser to do this now rather than when the tank is coming down. then you'll want to remove the small plastic splash guard in the left wheel well. this will give you access to the sending unit. unplug it. chances are the connector will fight you a bit coming off and will be stiff. be patient with it.

you will then want to remove the two 14mm bolts holding the tank up, move the straps down, and work the tank down. get the tank on the ground and remove the pickup lines and the fuel level sender. you may find the screws for the fuel level sender very rusty and difficult to remove..of course you are in NC so i doubt that thats the case... you can now look in the tank and make a determination of where you want to go from there. when the tank is clean you will want to replace the gasket for the fuel level sender and the gasket for the pickup lines. you may also want to replace the pickup screen that attatches to the pickup lines. this can be clogged or ripped or otherwise in poor condition. the part numbers for replacement parts from mazda are as follows:

pickup/return line gasket: FA54-42-182

fuel level sender gasket: 8871-60-962A

pickp screen: GA97-42-113

fuel tank pad: 8871-42-761

fuel level sender(if yours is bad. new sender comes with gasket): FA54-60-960

i have recently purchased most of these parts for my project and the prices are pretty reasonable from the dealer.

mazdaverx713b

iTrader: (91)

here are the instructions with pics for the tank removal:

first, jack the car up, put it on stands, remove the left rear wheel, remove the plastic splash shield in the left wheel well. it is held on by two 10mm bolts and a 10mm nut. this will expose the fuel level sender which needs to be unplugged at this step:



next, open the filler door, remove the gas cap and the three 8mm bolts, lift off the plate and push the neck down until it breaks away from the body:



now is a good time to drain the gas. place a suitable bucket under the drain plug and remove the drain plug. a clean 5 gallon bucket works great and you can empty the bucket into a 5 gallon gas can or cans:



after the tank is drained, reinstall the drain plug and remove the clamps from the feed, return, and vent lines and slide the hoses off:



once thats done, remove the 14mm bolt from from each tank strap, they'll be in the front of the straps towards the rear bumper and you'll want to swing the straps down:



when the tank starts coming down, wiggle the filler neck out of its opening. once you do this, the tank will finish coming down(all the while you are supporting the tank with your leg or suitable support i hope)



and the tank will be down and ready for service:



once you are satisfied with the tank, install is the reverse of removal. wiggling the filler neck into its opening while installing the tank at an angle is the toughest part. once everything is set in place, you'll bolt the straps up, install the lines, install the filler hose and cap, connect the sender connector, install the splash shield, install the tire, lower the car down, fill the tank with gas, start, and check for leaks.

here is the new pickup gasket and fuel level sender with screws installed





reinstall the tank and add a coat of undercoating to preserve the sender and protect it and the screws from rust. you may also want to clean and undercoat the entire top of the tank while it out to preserve it:

mazdaverx713b

iTrader: (91)

make any progress on finding the source of your problem?

rxmadness

iTrader: (1)

well i havent done anythign yet...i think its a ground or bad connector problem with the sending unit cuz latley when i hit bumps on the road my gauge will randomly work on and off...ill let you know
thanks