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Old 08-09-2011, 01:41 PM   #1
Jeff928S4
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Default Fuel leak....in tank pump? (with pics) - FIXED!!

Noticed a smell of gas the other day....then saw the drip, drip, drip from the rear of the car. Thought it was the tank at first, but noticed it only dripped when the car was running/for about 1 minute after it is shut off - then the drip stops.

Figured it was a connector to the external fuel pump.....took of the rear cover and checked the exterior pump....had a slight amount of gas on the bottom.....

(sorry for the grainy pics)



Started the car and no drip right away. Eventually gas started to drip from around this area (just before the "bump")...



My guess is that it is leaking around this area (as it seems to be pooling right below this area)....is the infamous "in-tank pump"?....




Here is about how much gas is leaking out....



So....is the pump gone or is it a seal or something like that? If it were a seal, wouldn't it leak all the time?

I see there are two larger nuts that appear to hold the rest of the tank strap/cover in place - if I remove that cover, can I access the in-tank pump to replace it/change the seal?

Also, judging by the amount of gas it is leaking - how far is a safe distance to travel with it like this? I may need to drive around 15-20 mins to where I can get it looked at.
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Last edited by Jeff928S4; 08-26-2011 at 02:25 PM.
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Old 08-09-2011, 03:08 PM   #2
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Just had a similar problem.

Some good pics and info here...

http://forums.rennlist.com/rennforum...ank-strap.html

Your problem is either the crush washers that seal on the line from the fuel pump to the filter, or the seal on the fitting that comes out of the tank.

Turned out mine was a simple seal (Item #3 in dwg.)on the fitting that goes into the tank. Not sure about the correct part # on the seal, but I followed another posters story on here and just used an O-ring that I bought for $1 down at the local franchise auto store. If you are ordering a new tank to fuel pump hose, you can order the correct seal at the same time.

That's the positive news. Now for the work...

The strap holding the tank has four bolts. Two back by the bumper, one in the rear wheel well area and one up by the rear of the transaxle. All should be obvious when you crawl under there.

You are going to need to disconnect the rubber fuel line that comes out of the tank and goes to the fuel pump. It is a moulded rubber line, around $15 from any of the suppliers. I replaced mine, not so much that it needed it, but rather I have been replacing all rubber as I go with the car. Also I have found that if I do not have the part ready in advance, I find I need it when I get everything apart and then it is a week to wait for the part so I can finish. Another reason for having the part on hand is some posters on here have noted that it is easier to cut off old hoses rather than trying to break them loose by twisting and potentially damaging something else down the line.

Once you are ready to do this, you should try to use up as much of the gas in the tank as possible. It is really messy to have it running own your arm as you pop off the hose. (Search "gas tank removal" for a better understanding about your project. You will not need to remove the tank, but you will find details about the bracket removal in them).

With the tank empty you can remove the support bracket. From your pic's you might want to plan to take the bracket out, clean it up an repaint it. You can leave the pump and filter on the bracket, but you will need to disconnect the wiring to the fuel pump(s) ( 7mm and 8 mm wrench) and disconnect the flare nut (19mm) on the line out of the fuel filter. Even with the tank drained this is messy and lots of gasoline spillage. Might want to do this outdoors or have lots of rags available to clean up and dispose of right away.

Before removing the bracket, you will want to support the tank. Many posters say it will just stay in place and it indeed seemed to, but I was overly cautious and cut a few 2 x 4's to prop it up just in case.

With the bracket out you can now easily get to the fuel tank fitting. There are lots and lots of horror stories on this forum about this fitting. Apparently it screws into a nut that has been cast into the tank (plastic) and far too often the nut appears to have broken loose instead of the fitting unscrewing. Mine just unscrewed. Cleaned it up an replace the seal.

If you have an in-tank pump you may want to research removing it. I do not have one, but there are lots of posts on the list about how it is not needed.

As a side note, you may find the support bracket to be very rotted. It has four arms, one of which is made to encase the fuel line out of the filter and up into the wheel well. Mine was so rotted that I reinforced it with fiberglass and JB Weld.
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Old 08-09-2011, 05:04 PM   #3
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Thanks so much Joe!!

So, that fitting in my pic is not necessarily the in-tank pump? Does the fitting look the same whether there is a pump in there or not?

Also, I may end up doing this on a hoist - I assume the same procedure, but just with longer pieces of 2x4 to support the tank.

One of the back support straps looks almost new - the other is rather rusted.

I had planned on taking the metal guards off and scrap them down and re-paint them, so this is sort of a timely leak. Hopefully it is only the seal where the fitting goes into the tank. I don't think it is the crush washer from the pump to the filter, as that area was pretty much dry. I can't physically see where the gas is leaking from, but do see where it pools and drips, so I suspect it is something around where the fitting sits in the tank.

Will report back with diagnosis and pics once the tank straps are off!! Thanks again.
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Old 08-09-2011, 05:17 PM   #4
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Opps, I forgot one thing.

If it is a seal or a washer, does the leak only surface when the car is running due to pressure? If the seal around that fitting was leaking, would it also leak with the car just sitting and not running?
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Old 08-09-2011, 07:41 PM   #5
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There shouldnt be any pressure change on the in-tank gasket/seal between pump NOT running and running - just the amount of fuel in the tank is relevant. IMHO, leak is much more likely at a joint - hose from tank to external, pump to to filter. I would clamp off the tank->external hose, remove external pump & filter assy , dismantle on bench, fit new copper washers and re-assemble, re-test on car, before going for a tank removal.
jp 83 Euro S AT 53k BTDT.
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Old 08-09-2011, 07:50 PM   #6
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I plan on putting in a new filter, so I'll pull the filter/external pump and re-assemble and see if it makes a difference.

I am also leaning towards it being a leak at a joint - but I think it is a joint somewhere around where the tank fitting is.

When I ran the car and climbed under the back to take a peek, I could not see any visible gas leaks around the external pump/filter inlet or outlet tubes - then gas just started dripping pretty much right below where that fitting is.
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Old 08-09-2011, 09:43 PM   #7
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Gas will weep from the source to all sorts of places, making it very hard to find the real starting point. As another suggested, think about removing the intank pump in favour of a filter - they cause more trouble than they are worth. my car has never had an in-tank, and it lived through years in a 120F environment.
jp 83 Euro S AT 53k, ex Saudi Arabia
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Old 08-10-2011, 08:23 AM   #8
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I have not seen an in-tank pump, but from what I can see on the parts catalog, it should look the same externally as just the filter. The telltale would be the in-tank pump would have wires going to it.

IMPORTANT....DISCONNECT THE BATTERY FIRST!

While there should not be power to the fuel pumps, you do not want to be disconnecting wiring down there with all that leaking gas.
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Old 08-10-2011, 01:12 PM   #9
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In my third pic, it seems there is a wire going to that fitting. Where would one source a screen/filter to replace the pump? (which I will do when the pump kicks the can)
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Old 08-10-2011, 01:50 PM   #10
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We stock the intank filter for $44 and you will need a new hose.
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Old 08-26-2011, 03:44 PM   #11
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UPDATE!!

Pulled the tank support cover off and found the problem.....

The clamp on the hose that runs from the in-tank pump to the external pump had literally rusted completely away....and the hose was very soft at the first bend.

We were going to attempt to pull the hose without draining the tank first (a quick switch), but when we pulled the hose off the side of the external pump - no gas came out. We blew compressed air in through the in-tank pump and it must have opened a flap/valve and gas flowed for a second.

Decided to pull the in-tank pump while we where there - it turned very easily - no stripping the seating. The filter on the pump was relatively clean and the bottom of the tank was pretty clean also (wiped it out with a rag).

It's neat how the tank has that lil' "bowl" on the bottom to store gas under what looks like a plastic baffle - no way the pump can ever be starved of gas during hard corners/bumps, as gas cannot splash back up into the tank itself. I assume that is why it is designed that way.

Changed the fuel filter while we were there.

I didn't completely remove the gas tank strap - took out all four of the bolts and just let it sit there so we could get at the in-tank pump - didn't have to support the tank either (ran down the fuel really low and only a small amount came out when we pulled the pump. We left the lines that run from the fuel filter up alongside the tank stay where they were). Because the front cover wasn't completely dropped, we used compressed air to blow all the sand/mud/dirt from the bottom of the cover - it flew EVERYWHERE - lots and lots of crap in there. Glad I got it cleaned out.

Some people here have mentioned how it is hard to get at the bolt that is closest to the transaxle....some said they needed to go around a bend to get at it. Turns out - if you pull the heat shield off the side of the tank strap/cover, there is a nice lil' hole in the cover to put a wrench up through to hit right on that one screw. The hole is hidden when the heat shield is on.

Here are some pics of the hole....







Finding that hole was pretty helpful.

We patched it all back together and I used outdoor foam mounting tape (as it it is slightly padded) to make new pads that sit between the tank and the straps. I left the red stuff on one side of the tape so that I had a non-porous surface touching the metal straps to prevent further rusting.....

This kind of tape....



Here is the tape in place....





Hopefully it stands up to the elements.

Also, I sprayed the old rear cover (and used aluminum tape to patch a rusty stop) with rust paint. The bigger cover didn't come off, so I just painted the bottom while it was on the car.

Before....



After.....



Here is the old rear cover....






...and how it looks now....










You will note there is now aluminum tape under my car. After everything was put back together, I noticed some gaps between the front and rear covers and on the sides of the plastic cover that the fuel lines run inside, so I figured I'd use the extra tape to seal off these gaps....












It's pretty much unnoticeable when looking at the car from the rear...




...although, when looking at the rear wheel well, you can see the tape if you are at the right angle....








Hopefully that tape will keep out the bigger things like sand/small rocks and cut down on accumulation in the bottoms of the covers (and thus keeping the in-tank pump hose and other components safer) - but I posted this idea in another thread and was asked how the water was going to drain out - didn't think of that at the time. I figure it will drain out the small hole in the larger front cover?



Like I said in the other thread, I could always poke a few holes in the tape for drainage if needed.

The car runs way better now - the past lil' while I had a slight "burble" when sitting at lights and the car would hesitate for a second or two in the mornings after starting it up (like it would on a cold day). Both those problems are now gone. I suspect the leaking hose was causing the exterior pump to suck the odd mouthful of air.
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Old 08-26-2011, 03:44 PM
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