Gas Tank Rust

[ZCurves]

Fuel Injected Right? If so,

Did you change the big metal filter by the engine? Did you check and clear the screen filter located inside the fuel pump inlet? Put key in and turn to "ON" and then unplug the oil pressure plug. (On later S30's this will force the Fuel Pump to run). Make sure the new clear filter is flooding nicely. You could remove the fuel line after the big filter up front and make sure that you are getting fuel. Ok, so if you are getting fuel - you might check to see if you are getting enough pressure - BUT the car would still fire and therefore run. Speaking of fire, are you getting a spark? Check that too. Now, if the car fires up, remember to plug the oil pressure plug back on and then just let it run at idle for 10 - 15 mins while the car gets rid of trapped air in the system. Take a look at the little clear filter. You'll notice lot's of bubbles but not too much debris- but just run a tank or two through it and look again to see if it needs changing.

[siteunseen]

What Andrew said about that cone filter going into the fuel pump. Is it clean? That G3 out of the tank should be full. On my early '77 you can unhook that small flat connector on the starter and turn on the switch and my pump will run. If it's running take off the line before the rail and see what kind of flow you have, into a jug or something.

[bhermes]

Going to look at G3 filter this morning and then aft of the filter that is in the engine bay to see if I am getting fuel. Before dropping the tank the car was running ok. It broke down as usuall, about once a week, and I assumed that this was the rust in the tank. Waited about 1 hour and the car started but did not run well. Appeared to be struggling for gas. After about 2-3 miles apparently the rust particle(s) broke free and the car ran fine. Drove another 1/4 mile to the house and thats when I decided and started to remove the tank. So I am assuming at this point it is a fuel delivery issue. When these cars run out of gas are the normally difficult to restart? Should I be priminmg something to help get it started. Again bare with me I have never been a mechanic but bought the car to learn what I could.

[bhermes]

I think I found the problem. I added a short piece of fuel line from the tank to the G3 filter and then used the existing fuel line from the G3 to the pump. I think the line from the G3 to the pump is pinched causing an issue with getting fuel into the systme. Not sure but will confirm soon. I am a little affraid to alter the fuel line in case for some reason I decide to remove the G3 filter later. Any concerns with the G3 filter adding additional pressure requirements on the pump or system? How often is the G3 needing replacement for those that have added in this application? Is this fuel line difficult to get if I need a new one?

[bhermes]

Sorry if you get this twice not sure what happened. I think I found the problem. I added a short line from the tank to the G3 filter and used the existing line and put from the G3 to the pump. I think the G3 to the pump fuel line is pinched causing fuel delivery issues. I moved it a bit and seemed to get some flow. Charging battery and will try to start soon. I am a little affraid to cut the exisiting fuel line in case I decide to remove the G3 filter later. A few questions; is it hard to find replacement fuel lines if I need the original tank to pump line, how often will I need to replace the G3 filter, and is anyone concerned that the G3 filter is adding additional load on the pump or rest of system?

[bhermes]

Good and Bad news. The car finally started. Not sure exactly what caused it to start. I took line aft of engine bay filter off at rail side and had no fuel flowing. I had about 2 gallons of gas in the tank. The car was on a slight uphill back to front elevation. I added a couple more gallons and moved the car where the front was lower than the back. The car started and idle good. I let idle for about 10-15 minutes and decided to drive on the road. Over about a mile stretch the car tried to die 3 times as the fuel damand increased.

I am suspected the fuel pump and fuel filter (both have only about 500 miles on them but that is probably 500 miles of rusty gas. My other thought is a hole in the pick up line in the tank.

Any thoughts? I am going to again check flow after the fuel filter to see what the flow looks like.

One of the posts talked about a filter at the inlet of the pump. I assume this is part of the pump. A little confused on if this is clogged what to do.

[siteunseen]

Sounds like your going to need a fuel pressure gauge. They're cheap money instead of guessing or replacing parts that aren't bad. The inlet port on the pump, if it's a Bosch OE, has a cone shaped screen filter smaller than a thimble in it. I used tweezers to get mine out. They're real fragile if they're OE. Blast it with carb cleaner if it's dirty. Your about to be over my head and need the pros.

[bhermes]

Well, looked at the engine area filter again. Took off completely and observed fuel on inlet side and fuel on outlet side. Fuel coming into the filter seemed extremely clean while fuel coming out of the filter was dirty and had some small rusty looking flakes. Hopefully a new filter will solve the problem. Also hooked the filter back up minus the line to the injectors and appeared to be getting decent flow but again a little dirty.

Is there something I can run through the fuel system that might help things; i.e., fuel injector cleaner?

[bhermes]

Repalced the filter and let the car idle for a little while. I then rev'd the enginer up and down between idle and 4000 rpms. Seemed good but every now and then I would get a little hesitation.

Mystery may have been solved. When I bought the car it did not have an ignition switch. I have since added one; however, I noticed a lot of wire splicing just after the switch. Today as I was running the car I tapped the spliced wires and the car wanted to shut off. Same thing each time that I tapped on the wires.

Need to get into a little further but guessing this is the final piece of the puzzle. Will confirm and close out this post.

Gas seems to be running clean with no rust and no red kote.

Thanks to all who posted and commented it has been a very valuable thread at least for me.

[bhermes]

6 pin connector on back of ignition switch not holding and mating tabs properly. Females connectors ar not mating securily to the tabs on the back of the switch. Not sure if the housing is supposed to hold the females or when mated to the tabs the housing just sits there. Will find out soon.