Plastic expansion tank gasket, Gas smell |
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Plastic expansion tank gasket, Gas smell |
Medtner3 |
Jul 24 2020, 07:31 AM
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#1
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Member Group: Members Posts: 180 Joined: 7-July 20 From: Cedar Park Member No.: 24,467 Region Association: None |
Still struggling with gas odor in front trunk around expansion tank
Installed a new gasket between the fuel tank and expansion tank, and there is a metal ring on top—Just trying to verify the gasket placement is there supposed to be another gasket under the metal ring or is mine in the wrong placement. The fuel odor seems to be coming from that area so I also ordered a new gas cap seal and I have already replaced the 4-5mm hoses to the expansion tank . And already replaced gasket under fuel sensing unit all the bolts are tight Today I was going to see if it’s possible to lift the tank and check all the hose connections. All the hoses are new with new clamps. The inlet tubes are not leaking Edit: checked under tank it’s bone dry and zero smell whatsoever so now consider that unless I’ve done something wrong on the expansion tank install that the odor must be the fuel cap gasket even though it’s super tight and nothing visible wrong. Have ordered one |
dangrouche |
Jul 24 2020, 08:57 AM
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#2
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dangrouche Group: Members Posts: 550 Joined: 1-May 04 From: San Francisco Bay Area Member No.: 2,012 Region Association: None |
Still struggling with gas odor in front trunk around expansion tank Installed a new gasket between the fuel tank and expansion tank, and there is a metal ring on top—Just trying to verify the gasket placement is there supposed to be another gasket under the metal ring or is mine in the wrong placement. The fuel odor seems to be coming from that area so I also ordered a new gas cap seal and I have already replaced the 4-5mm hoses to the expansion tank . And already replaced gasket under fuel sensing unit all the bolts are tight Today I was going to see if it’s possible to lift the tank and check all the hose connections. All the hoses are new with new clamps. The inlet tubes are not leaking Edit: checked under tank it’s bone dry and zero smell whatsoever so now consider that unless I’ve done something wrong on the expansion tank install that the odor must be the fuel cap gasket even though it’s super tight and nothing visible wrong. Have ordered one there is supposed to a large circular rubber gasket beneath those 8mm screws. Its like 2 mm thick, you could probably make one out of cork or sheet gasket material Attached thumbnail(s) |
dr914@autoatlanta.com |
Jul 24 2020, 08:59 AM
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#3
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914 Guru Group: Members Posts: 7,866 Joined: 3-January 07 From: atlanta georgia Member No.: 7,418 Region Association: None |
yes maybe the lines on the bottom of the tank are weeping, pull the tank up and look
Still struggling with gas odor in front trunk around expansion tank Installed a new gasket between the fuel tank and expansion tank, and there is a metal ring on top—Just trying to verify the gasket placement is there supposed to be another gasket under the metal ring or is mine in the wrong placement. The fuel odor seems to be coming from that area so I also ordered a new gas cap seal and I have already replaced the 4-5mm hoses to the expansion tank . And already replaced gasket under fuel sensing unit all the bolts are tight Today I was going to see if it’s possible to lift the tank and check all the hose connections. All the hoses are new with new clamps. The inlet tubes are not leaking Edit: checked under tank it’s bone dry and zero smell whatsoever so now consider that unless I’ve done something wrong on the expansion tank install that the odor must be the fuel cap gasket even though it’s super tight and nothing visible wrong. Have ordered one |
914sgofast2 |
Jul 24 2020, 09:04 AM
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#4
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Senior Member Group: Members Posts: 617 Joined: 10-May 13 From: El Dorado Hills, CA Member No.: 15,855 Region Association: None |
Maybe your gas tank has a hole in it. I found that my tank had a hole in it due to rust eating it away from the felt pads glued to the tank where it rests against the body. Several used tanks I looked at also had the same problem. The leak isn’t bad enough to leave a puddle or drip, but it leaks enough for you to always have a gasoline smell in the trunk.
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Medtner3 |
Jul 24 2020, 09:35 AM
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#5
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Member Group: Members Posts: 180 Joined: 7-July 20 From: Cedar Park Member No.: 24,467 Region Association: None |
Maybe your gas tank has a hole in it. I found that my tank had a hole in it due to rust eating it away from the felt pads glued to the tank where it rests against the body. Several used tanks I looked at also had the same problem. The leak isn’t bad enough to leave a puddle or drip, but it leaks enough for you to always have a gasoline smell in the trunk. Thanks brand new gas tank so not likely |
Medtner3 |
Jul 24 2020, 09:40 AM
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#6
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Member Group: Members Posts: 180 Joined: 7-July 20 From: Cedar Park Member No.: 24,467 Region Association: None |
Still struggling with gas odor in front trunk around expansion tank Installed a new gasket between the fuel tank and expansion tank, and there is a metal ring on top—Just trying to verify the gasket placement is there supposed to be another gasket under the metal ring or is mine in the wrong placement. The fuel odor seems to be coming from that area so I also ordered a new gas cap seal and I have already replaced the 4-5mm hoses to the expansion tank . And already replaced gasket under fuel sensing unit all the bolts are tight Today I was going to see if it’s possible to lift the tank and check all the hose connections. All the hoses are new with new clamps. The inlet tubes are not leaking Edit: checked under tank it’s bone dry and zero smell whatsoever so now consider that unless I’ve done something wrong on the expansion tank install that the odor must be the fuel cap gasket even though it’s super tight and nothing visible wrong. Have ordered one there is supposed to a large circular rubber gasket beneath those 8mm screws. Its like 2 mm thick, you could probably make one out of cork or sheet gasket material I have the plastic tank I have it in this order: fuel tank—>rubber 2mm thick gasket—>plastic expansion tank —> metal ring I did not put a gasket under metal ring |
914werke |
Jul 24 2020, 09:51 AM
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#7
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"I got blisters on me fingers" Group: Members Posts: 10,081 Joined: 22-March 03 From: USofA Member No.: 453 Region Association: Pacific Northwest |
Does the appearance of gas fumes coincide with filling the tank? Hint
No other gasket than the one tween tank & expansion (plastic) tank. I have seen it installed ..off.. allowing gas & fumes to escape. The serrated ring is just to support clamping onto the plastic by the 6mm bolts |
Medtner3 |
Jul 24 2020, 10:01 AM
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#8
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Member Group: Members Posts: 180 Joined: 7-July 20 From: Cedar Park Member No.: 24,467 Region Association: None |
Does the appearance of gas fumes coincide with filling the tank? Hint No other gasket than the one tween tank & expansion (plastic) tank. I have seen it installed ..off.. allowing gas & fumes to escape. The serrated ring is just to support clamping onto the plastic by the 6mm bolts Possibly mine is installed off I will remove and check for leaks and proper install tks |
Medtner3 |
Jul 24 2020, 10:03 AM
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#9
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Member Group: Members Posts: 180 Joined: 7-July 20 From: Cedar Park Member No.: 24,467 Region Association: None |
Does the appearance of gas fumes coincide with filling the tank? Hint No other gasket than the one tween tank & expansion (plastic) tank. I have seen it installed ..off.. allowing gas & fumes to escape. The serrated ring is just to support clamping onto the plastic by the 6mm bolts No correlation to filling tank. Tks for clarifying ring |
Medtner3 |
Jul 24 2020, 10:07 AM
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#10
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Member Group: Members Posts: 180 Joined: 7-July 20 From: Cedar Park Member No.: 24,467 Region Association: None |
yes maybe the lines on the bottom of the tank are weeping, pull the tank up and look Still struggling with gas odor in front trunk around expansion tank Installed a new gasket between the fuel tank and expansion tank, and there is a metal ring on top—Just trying to verify the gasket placement is there supposed to be another gasket under the metal ring or is mine in the wrong placement. The fuel odor seems to be coming from that area so I also ordered a new gas cap seal and I have already replaced the 4-5mm hoses to the expansion tank . And already replaced gasket under fuel sensing unit all the bolts are tight Today I was going to see if it’s possible to lift the tank and check all the hose connections. All the hoses are new with new clamps. The inlet tubes are not leaking Edit: checked under tank it’s bone dry and zero smell whatsoever so now consider that unless I’ve done something wrong on the expansion tank install that the odor must be the fuel cap gasket even though it’s super tight and nothing visible wrong. Have ordered one Yes possibly will check odor is around gas cap. Why did they make those lines so hard to get to danggit they needed a Dr914 on their design team at Porsche |
Mikey914 |
Jul 24 2020, 10:39 AM
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#11
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The rubber man Group: Members Posts: 12,670 Joined: 27-December 04 From: Hillsboro, OR Member No.: 3,348 Region Association: None |
It is possible the seal in the gas cap is torn or missing. You mentioned the tank is new. You may just need one of these -
https://900designs-container.zoeysite.com/s...steel-gas-cap-1 But it could be the seal itself. You mentioned "plastic" is should be a rubber seal so perhaps it hardened not making a good seal? Attached thumbnail(s) |
Medtner3 |
Jul 24 2020, 11:10 AM
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#12
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Member Group: Members Posts: 180 Joined: 7-July 20 From: Cedar Park Member No.: 24,467 Region Association: None |
It is possible the seal in the gas cap is torn or missing. You mentioned the tank is new. You may just need one of these - https://900designs-container.zoeysite.com/s...steel-gas-cap-1 But it could be the seal itself. You mentioned "plastic" is should be a rubber seal so perhaps it hardened not making a good seal? Ordered new one my original is indeed paper and possibly 46 years old? |
rhodyguy |
Jul 24 2020, 06:15 PM
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#13
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,081 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
That line pictured goes to a port on the pass side, right, of the fuel tank expansion chamber. Air from the area around the cap to the chamber. A vacuum line. The draw off port is on the other side of the chamber. What is hooked up to that port? Haynes P 56. Is your charcoal vapor canister hooked up? Eventually, that air gets sucked into the engine.
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Medtner3 |
Jul 24 2020, 06:20 PM
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#14
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Member Group: Members Posts: 180 Joined: 7-July 20 From: Cedar Park Member No.: 24,467 Region Association: None |
That line pictured goes to a port on the pass side, right, of the fuel tank expansion chamber. Air from the area around the cap to the chamber. A vacuum line. The draw off port is on the other side of the chamber. What is hooked up to that port? Haynes P 56. Is your charcoal vapor canister hooked up? Eventually, that air gets sucked into the engine. All the lines to the expansion tank are plugged. I am trying to find a canister. The small line on the right goes under the car through the tunnel and it’s plugged in the engine bay |
rhodyguy |
Jul 24 2020, 07:10 PM
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#15
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,081 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
The small line in the picture is plugged? With what? The other small port capped? That pass side port/pipe goes directly to the fuel tank. Thru the fill neck. Under the cap. Direct line to the atmosphere. This is part of the reason your car smells like fuel. Gaskets won't fix what's wrong.
Edit. The center tunnel? The interior? That small line connects to the expansion chamber. Not to something in the engine compartment. What does the line connect to once in the engine compartment? Does your car have fuel injection or carbs? |
BillC |
Jul 24 2020, 07:13 PM
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#16
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Senior Member Group: Members Posts: 539 Joined: 24-April 15 From: Silver Spring, MD Member No.: 18,667 Region Association: MidAtlantic Region |
Check to make sure all 8 screws are in place. All 8 holes go through into the tank, so any screw missing will allow vapors out of the tank.
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Medtner3 |
Jul 24 2020, 09:18 PM
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#17
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Member Group: Members Posts: 180 Joined: 7-July 20 From: Cedar Park Member No.: 24,467 Region Association: None |
Check to make sure all 8 screws are in place. All 8 holes go through into the tank, so any screw missing will allow vapors out of the tank. Seems to be a slight bend upwards by one screw but I would think the gasket would take care of any slight irregularities in the tank |
Medtner3 |
Jul 24 2020, 09:22 PM
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#18
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Member Group: Members Posts: 180 Joined: 7-July 20 From: Cedar Park Member No.: 24,467 Region Association: None |
The small line in the picture is plugged? With what? The other small port capped? That pass side port/pipe goes directly to the fuel tank. Thru the fill neck. Under the cap. Direct line to the atmosphere. This is part of the reason your car smells like fuel. Gaskets won't fix what's wrong. Edit. The center tunnel? The interior? That small line connects to the expansion chamber. Not to something in the engine compartment. What does the line connect to once in the engine compartment? Does your car have fuel injection or carbs? Not my picture btw. I have FI My small line on the pass side goes from the expansion tank to the fuel tank. The small line on drivers side goes to a black plastic line that runs through the center tunnel to the engine bay where I have it plugged. I am working on getting a charcoal canister to connect it |
Medtner3 |
Jul 25 2020, 09:16 AM
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#19
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Member Group: Members Posts: 180 Joined: 7-July 20 From: Cedar Park Member No.: 24,467 Region Association: None |
Picture of where I smell fuel. Yesterday lifted expansion tank off and put a new gasket. Not sure what the torque spec is for the eight bolts around the metal ring but I have them tight and the previous gasket seemed a little overly compressed form my tightening it th try and stop the odor.
I lifted the tank and checked all connections. All right and zero smell of gas at any connections or visible weeping at my all new fuel lines. The gas tank is new. The only thing I don’t have is a charcoal canister but the lines from the canister as J described one goes from expansion tank to filler neck and the drivers side line runs through tunnel to the engine bay. I traced this line and Cambodians any breaks in it. Ideas? Could the lack of canister or fuel cap gasket be the problem? I guess I will have to wait until I replace those parts Attached thumbnail(s) |
davesprinkle |
Jul 25 2020, 09:19 AM
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#20
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Senior Member Group: Members Posts: 720 Joined: 13-October 04 From: Berkeley, CA Member No.: 2,943 Region Association: None |
The small line in the picture is plugged? With what? The other small port capped? That pass side port/pipe goes directly to the fuel tank. Thru the fill neck. Under the cap. Direct line to the atmosphere. This is part of the reason your car smells like fuel. Gaskets won't fix what's wrong. Edit. The center tunnel? The interior? That small line connects to the expansion chamber. Not to something in the engine compartment. What does the line connect to once in the engine compartment? Does your car have fuel injection or carbs? Not my picture btw. I have FI My small line on the pass side goes from the expansion tank to the fuel tank. The small line on drivers side goes to a black plastic line that runs through the center tunnel to the engine bay where I have it plugged. I am working on getting a charcoal canister to connect it You shouldn't plug this line. It is the vent for the entire fuel tank. If the vent is plugged, the system will find some other vent path, in your case likely past an imperfect gasket somewhere. Might explain your fuel smell. You should prioritize the charcoal canister. When it's installed correctly, there is no fuel smell. Works really well. |
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