Bad gas or what?
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From: NE OHIO
1998 SL500,2011 GL550,2009 ML350,past 1995 E320 Cabrio ,2005 ML500,2006 ML500,1996 SL500,1972 280SEL
2 prong tool
Eric… Mr Salty here ..I am 69 yrs old and have rebuilt many engines , cars, etc. I built complete MRI vans and much more medical equipment… Just face it the 2 prong tool is junk. If you can remove the lid with the 2 prong tool you didn’t need a tool and a simple punch or screwdriver would have done the job. Downward force won’t matter when you are dealing with plastic on 2 prongs with a torque of over 50ftlbs .
Please let us know if the $33 ebay tool fits properly.. I bet it will work great.
The reason I went with a Urathane body panel caulking is because it is gas proof. The cover plate will seal gas fumes from the interior in case something goes wrong with the tank fittings .
Please let us know if the $33 ebay tool fits properly.. I bet it will work great.
The reason I went with a Urathane body panel caulking is because it is gas proof. The cover plate will seal gas fumes from the interior in case something goes wrong with the tank fittings .
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NGL450 w/EORP, S550
Gas fumes are a great indicator that your lock rings are either subpar or have failed so I just need something flexible that is gas resistant to hold the lids in place until I can come back and fix it… Not that it is necessary
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NGL450 w/EORP, S550
So no it’s…. or what
So, it happened again. Brand new MB pump and filter.
i had another soft power loss with 1/4 tankful showing, but I’m not sure I had 1/4 tank and we will get to that later.
I opened up the pump lid and tapped on the tank from below. All while on the side of the road. No change.
i called a rescue and put in 2 gallons and it fired right up. Drove to the nearest gas station and filled it until it clicked off - 21 gal it took. So let’s do some math here:
at 1/4 tank should have 26.3/4 = 6.6 gal remaining. Plus the two added in, 8.6 total it should have have only took 17.7.
21 gal filled minus 17.7 it should have taken if the gauge weee accurate that leaves a delta of 3.3 gal which incidentally is the capacity of the emergency reserve part of tank.
so I think that I installed the filter so that it is unable to access the last 3.3 gal in the tank, and that the float on it is hung up on one of the tubes/wires and lying to me by saying I have more gas than I really do.
and I really don’t wanna open up the driver side again to check this…
I ran a short test and there were no codes for implausible mismatch between the two floats, and I’m not even sure it measures that, also ran a fuel tank pressure test, which passed, but again it’s so darn hard to troubleshoot fuel pump in this car. The only thing you can do is turn it off and on to make sure that it turns off. Which is marginally useful.
throwing this one to you guys to throw peanuts at my math in public, and see if there’s any particular way, the filter needed to be rotated, and the tube ran towards the front of the tank…
but until that day, I’m just gonna keep it over half full and curse myself a little bit.
i had another soft power loss with 1/4 tankful showing, but I’m not sure I had 1/4 tank and we will get to that later.
I opened up the pump lid and tapped on the tank from below. All while on the side of the road. No change.
i called a rescue and put in 2 gallons and it fired right up. Drove to the nearest gas station and filled it until it clicked off - 21 gal it took. So let’s do some math here:
at 1/4 tank should have 26.3/4 = 6.6 gal remaining. Plus the two added in, 8.6 total it should have have only took 17.7.
21 gal filled minus 17.7 it should have taken if the gauge weee accurate that leaves a delta of 3.3 gal which incidentally is the capacity of the emergency reserve part of tank.
so I think that I installed the filter so that it is unable to access the last 3.3 gal in the tank, and that the float on it is hung up on one of the tubes/wires and lying to me by saying I have more gas than I really do.
and I really don’t wanna open up the driver side again to check this…
I ran a short test and there were no codes for implausible mismatch between the two floats, and I’m not even sure it measures that, also ran a fuel tank pressure test, which passed, but again it’s so darn hard to troubleshoot fuel pump in this car. The only thing you can do is turn it off and on to make sure that it turns off. Which is marginally useful.
throwing this one to you guys to throw peanuts at my math in public, and see if there’s any particular way, the filter needed to be rotated, and the tube ran towards the front of the tank…
but until that day, I’m just gonna keep it over half full and curse myself a little bit.
Last edited by Max Blast; Apr 28, 2024 at 11:41 PM.
Super Member
Joined: Jul 2016
Posts: 705
Likes: 129
From: NE OHIO
1998 SL500,2011 GL550,2009 ML350,past 1995 E320 Cabrio ,2005 ML500,2006 ML500,1996 SL500,1972 280SEL
tank floats
So, it happened again. Brand new MB pump and filter.
i had another soft power loss with 1/4 tankful showing, but I’m not sure I had 1/4 tank and we will get to that later.
I opened up the pump lid and tapped on the tank from below. All while on the side of the road. No change.
i called a rescue and put in 2 gallons and it fired right up. Drove to the nearest gas station and filled it until it clicked off - 21 gal it took. So let’s do some math here:
at 1/4 tank should have 26.3/4 = 6.6 gal remaining. Plus the two added in, 8.6 total it should have have only took 17.7.
21 gal filled minus 17.7 it should have taken if the gauge weee accurate that leaves a delta of 3.3 gal which incidentally is the capacity of the emergency reserve part of tank.
so I think that I installed the filter so that it is unable to access the last 3.3 gal in the tank, and that the float on it is hung up on one of the tubes/wires and lying to me by saying I have more gas than I really do.
and I really don’t wanna open up the driver side again to check this…
I ran a short test and there were no codes for implausible mismatch between the two floats, and I’m not even sure it measures that, also ran a fuel tank pressure test, which passed, but again it’s so darn hard to troubleshoot fuel pump in this car. The only thing you can do is turn it off and on to make sure that it turns off. Which is marginally useful.
throwing this one to you guys to throw peanuts at my math in public, and see if there’s any particular way, the filter needed to be rotated, and the tube ran towards the front of the tank…
but until that day, I’m just gonna keep it over half full and curse myself a little bit.
i had another soft power loss with 1/4 tankful showing, but I’m not sure I had 1/4 tank and we will get to that later.
I opened up the pump lid and tapped on the tank from below. All while on the side of the road. No change.
i called a rescue and put in 2 gallons and it fired right up. Drove to the nearest gas station and filled it until it clicked off - 21 gal it took. So let’s do some math here:
at 1/4 tank should have 26.3/4 = 6.6 gal remaining. Plus the two added in, 8.6 total it should have have only took 17.7.
21 gal filled minus 17.7 it should have taken if the gauge weee accurate that leaves a delta of 3.3 gal which incidentally is the capacity of the emergency reserve part of tank.
so I think that I installed the filter so that it is unable to access the last 3.3 gal in the tank, and that the float on it is hung up on one of the tubes/wires and lying to me by saying I have more gas than I really do.
and I really don’t wanna open up the driver side again to check this…
I ran a short test and there were no codes for implausible mismatch between the two floats, and I’m not even sure it measures that, also ran a fuel tank pressure test, which passed, but again it’s so darn hard to troubleshoot fuel pump in this car. The only thing you can do is turn it off and on to make sure that it turns off. Which is marginally useful.
throwing this one to you guys to throw peanuts at my math in public, and see if there’s any particular way, the filter needed to be rotated, and the tube ran towards the front of the tank…
but until that day, I’m just gonna keep it over half full and curse myself a little bit.
a few weeks ago I thought about how flimsy the wire and floats were. When you stuff the pump, wires and float system into the openings… it sure won’t take much to bend anything and screw up the gas gauge floats…
Super Member
Joined: Jul 2016
Posts: 705
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From: NE OHIO
1998 SL500,2011 GL550,2009 ML350,past 1995 E320 Cabrio ,2005 ML500,2006 ML500,1996 SL500,1972 280SEL
MBWorld Fanatic!
Joined: Jun 2010
Posts: 2,762
Likes: 630
From: Emmett, ID, USA
2007 GL450
What does WIS say about the installation procedure?
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Thread Starter
MBWorld Fanatic!
Joined: Jan 2010
Posts: 3,119
Likes: 784
NGL450 w/EORP, S550
Super Member
Joined: Jul 2016
Posts: 705
Likes: 129
From: NE OHIO
1998 SL500,2011 GL550,2009 ML350,past 1995 E320 Cabrio ,2005 ML500,2006 ML500,1996 SL500,1972 280SEL
floats
If you do decide to take it apart .. one suggestion would be to align the bad pump/float next to the new one and make sure the floats are relatively set the same. I still have my old pump and can take pictures of the float angles if you need them .
The MB pump I bought was packed in foam protecting the float wires decently .
The MB pump I bought was packed in foam protecting the float wires decently .
Last edited by vesiadog; Apr 29, 2024 at 10:19 PM. Reason: wording
Thread Starter
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NGL450 w/EORP, S550
If you do decide to take it apart .. one suggestion would be to align the bad pump/float next to the new one and make sure the floats are relatively set the same. I still have my old pump and can take pictures of the float angles if you need them .
The MB pump I bought was packed in foam protecting the float wires decently .
The MB pump I bought was packed in foam protecting the float wires decently .
yeah, the old units are part of the earth now on some landfill… I should also have turned it on with the gas tank known empty to catch this issue
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NGL450 w/EORP, S550
but according to the math, I put in only enough fuel to fill up from the emergency reserve to full. So I wonder if the pipes/hoses coming from the filter to the pump need to be pushed out to the front of the driver side saddle to act as pick up for the last remaining 3 gallons.
does anyone here know where the emergency reserve capacity actually resides?
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From: Emmett, ID, USA
2007 GL450
no, it is pretty stiff wire but I think in rotating it in and out, I may have hooked the blue wire that goes over to the pump side around the filter float and that’s keeping it from going all the way down and showing empty. What I think. I will see if I open it up or put a camera in there with no gas in it whatsoever float down, and the filter side float hung up on a wire about halfway. The ECU then averages those inputs out to a quarter tank showing..
but according to the math, I put in only enough fuel to fill up from the emergency reserve to full. So I wonder if the pipes/hoses coming from the filter to the pump need to be pushed out to the front of the driver side saddle to act as pick up for the last remaining 3 gallons.
does anyone here know where the emergency reserve capacity actually resides?
but according to the math, I put in only enough fuel to fill up from the emergency reserve to full. So I wonder if the pipes/hoses coming from the filter to the pump need to be pushed out to the front of the driver side saddle to act as pick up for the last remaining 3 gallons.
does anyone here know where the emergency reserve capacity actually resides?
As you said, there were no codes for implausible level sensor, and it is not clear the system reports such things. Given that the system does not even report (or measure?) fuel pressure, I would not be surprised if the system just shrugs when it sees one side persistently reporting higher fill level than the other. So the filter side's float probably got hung up at the halfway point, and so the pump was sucking gas from the filter side, trying to equalize the two.
However, you refilled from a gas-out condition with just 23 gallons. That is the real puzzle.
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From: Emmett, ID, USA
2007 GL450
Or the fuel pump float is stuck up, and so the pump pushed fuel over to the driver side, to the point the pump began drawing air, with 3.4 gallons (or 6.8?!?) remaining on the driver side.
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NGL450 w/EORP, S550
I read out the individual float levels by interrogating the rear SAM with gas at known close to empty (gauge still showing 1/4).
not shown, but Wis states That each float level ranges from 10 to 214 ohms, 10 full and 214 empty. The reading above was taken with the tank completely empty after having pumped all of it out the fuel rail using the fuel pump..
The second reading is after adding 5 gallons… As you can see the b4/2 passenger side reading moves up accordingly, but b4/1 (drivers side) one does not so it is just hanging there in mid air stuck.
I so don’t want to do this again, but I seem to have no choice other than to dig in under the 60 portion of the backseat and get the lid off that I so tightly cemented in with permatex.
ugh.
But from what I gather, the emergency reserve capacity is basically the bottom 3 gallons of the entire tank… There’s no way that the crossfeed from the filter unit hose can reach into the deep pockets on either side. So that is actually picked up by the b4/1 filter side through the strainer sock that is pressed against the bottom bottom of the tank.
It gets to the fuel delivery side by motive flow that is created by the b4/2 pump on the other side… Crafty.
Last edited by Max Blast; May 10, 2024 at 12:30 AM.
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Joined: Jun 2010
Posts: 2,762
Likes: 630
From: Emmett, ID, USA
2007 GL450
yep, the driver side float is stuck.
I read out the individual float levels by interrogating the rear SAM with gas at known close to empty (gauge still showing 1/4).
not shown, but Wis states That each float level ranges from 10 to 214 ohms, 10 full and 214 empty. The reading above was taken with the tank completely empty after having pumped all of it out the fuel rail using the fuel pump..
The second reading is after adding 5 gallons… As you can see the b4/2 passenger side reading moves up accordingly, but b4/1 (drivers side) one does not so it is just hanging there in mid air stuck.
I so don’t want to do this again, but I seem to have no choice other than to dig in under the 60 portion of the backseat and get the lid off that I so tightly cemented in with permatex.
ugh.
But from what I gather, the emergency reserve capacity is basically the bottom 3 gallons of the entire tank… There’s no way that the crossfeed from the filter unit hose can reach into the deep pockets on either side. So that is actually picked up by the b4/1 filter side through the strainer sock that is pressed against the bottom bottom of the tank.
It gets to the fuel delivery side by motive flow that is created by the b4/2 pump on the other side… Crafty.
I read out the individual float levels by interrogating the rear SAM with gas at known close to empty (gauge still showing 1/4).
not shown, but Wis states That each float level ranges from 10 to 214 ohms, 10 full and 214 empty. The reading above was taken with the tank completely empty after having pumped all of it out the fuel rail using the fuel pump..
The second reading is after adding 5 gallons… As you can see the b4/2 passenger side reading moves up accordingly, but b4/1 (drivers side) one does not so it is just hanging there in mid air stuck.
I so don’t want to do this again, but I seem to have no choice other than to dig in under the 60 portion of the backseat and get the lid off that I so tightly cemented in with permatex.
ugh.
But from what I gather, the emergency reserve capacity is basically the bottom 3 gallons of the entire tank… There’s no way that the crossfeed from the filter unit hose can reach into the deep pockets on either side. So that is actually picked up by the b4/1 filter side through the strainer sock that is pressed against the bottom bottom of the tank.
It gets to the fuel delivery side by motive flow that is created by the b4/2 pump on the other side… Crafty.
My replacement fuel filter is sitting on my kitchen table. I played with the float a little and I can't see what the float would be getting hung up on. Did you open the tubing and wiring harness bundle at all?
If it would help, I can take pictures. But if you still have the old filter, that would probably be preferable.
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NGL450 w/EORP, S550
Thanks, Erik. I actually do have the old filter. I thought I threw it away, but did not.. the armature itself snaps onto the body of the filter and I’m wondering if it has come off and the float is just stuck in one position and floating freely in the tank.
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Joined: Jun 2010
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From: Emmett, ID, USA
2007 GL450
Based on what you saw when filling, it seems very much like the float is hung up on something.
I noticed the arm swings up and down in a slot in the plastic. If the arm got bent, it might be rubbing on the plastic and got stuck.
If the gauge mechanism is damaged, you could probably transfer the old one onto the new filter.
Side note: Hot melt glue might be good for sealing the top lid. Easy to remove with a heat gun.
I noticed the arm swings up and down in a slot in the plastic. If the arm got bent, it might be rubbing on the plastic and got stuck.
If the gauge mechanism is damaged, you could probably transfer the old one onto the new filter.
Side note: Hot melt glue might be good for sealing the top lid. Easy to remove with a heat gun.
