4th Cracked OEM Gas Tank on my 97 LX450 (1 Viewer)

Joined
May 5, 2021
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1
Location
Houston TX
In 18 months, I'm on my 4th gas tank from Lexus, always cracks in the same spot. The last one lasted 2 weeks before it started to leak. I've looked through several post in here, and I know it has been an issue with others. Has anyone every came up with a resolution? Is it just poor craftmanship on these tanks? Are the OEM tanks bigger and the straps are crushing the tank? Should I go back to a used tank from the 97 era?
Thanks for the help in advance.

Tank 1.jpg


tank 2.jpg
 
Joined
Sep 15, 2016
Messages
745
Location
Chattanooga, TN
One factor can be the tank becoming highly pressurized and then de-pressurized which causes flexing and can lead to cracks. I don't know if that is a factor here but you can add it to your list to look into. One clue would be lots of air/pressure escaping when you remove the gas cap.
 
Joined
Feb 28, 2012
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N. Phx
I did exactly what you're doing about 4-5yrs ago. The issue here is that the tank is expanding and contracting excessively which is causing oil-can deformation and stress cracking in that specific spot. The shape of the fuel tank allows that one section to be flexed back and forth which fatigues the metal until it breaks = fuel leaking off the top when full or sloshing. It's kinda scary if parked in a garage with a pilot light water heater.

After the original tank flexing and breaking and a new OEM being installed and breaking, Toyota took a close look at the pressurization controls and found a $2.50 vent / vacuum solenoid mounted at the upper intake manifold which was faulty, preventing the release of pressure in the fuel tank. The FSM refers to this part as the VCV Valve for Evap (vs. EGR), and theres a one-way valve upstream from intake manifold vacuum. This is most easily located by tracking the hoses from your Charcoal Canister to the valve under the intake manifold.
28773.jpeg
28772.jpeg


Once replaced, the tank pressurization was no longer an issue with big venting in or out when removing the gas cap, and the tank has not failed. Sorry I don't have a part number for you, I went out and looked through my receipts and couldn't find it. Good luck,
 
Joined
Aug 11, 2020
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Baton Rouge, LA
If there is hissing when you unscrew your gas cap, then it's probably your charcoal canister. Autozone sells a VC120 for around $50 that will solve your problems.
 

jfz80

Cruisin’
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Only 4 😆? BTDT so I feel your pain.

The CC did not cure mine. Long ducks suggestion is a good one; when vented to atmosphere but at the CC I still had a failure so the check valve is where I’d start. Finally swapped it and sourced a pre stressed beaten into 23gal submission used tank and I’ve been GTG since.
 
Joined
Aug 22, 2010
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Jersey, 07740
i would try to fine a shop that will do a tank repair for you. my tank cracked along the seam where the top and bottom halves meet, the dealership i was at used a rad repair shop that also did metal tank repairs. for 130 through the shop they brazed in a repair patch and the tank has been going strong for the last few years, you have very little to loose trying to repair the tank before dropping another 500+ on a tank if your going with a new tank
 
Joined
Sep 15, 2016
Messages
745
Location
Chattanooga, TN
@LongDuck which of the following do you think you had replaced:

vacuum control valve:​
90925-03192​
filter gas #1​
90917-10049​
vacuum switching valve​
90910-12043​

Or something else? The filter gas #1 is cheap as you describe but the VCV that's first in the list matches the rest of your description except it looks like it's around $100.

There more be more current part numbers than above and there a few other parts of the system that you may have had replaced. I'll be doing some testing as I have mild tank pressures even after checking out the C. canister and if there's another fix I'd like to employ it before needing to replace the tank.

Here's another diagram that may be useful:


Also, for reference the unrelated EGR VSV is:

90910-12079​
dorman 911-850​
 
Joined
Feb 28, 2012
Messages
1,018
Location
N. Phx
Throughout the diagnostic and the dealer putting in their own tank and having it fail shortly thereafter (within a week), I recall replacing these parts;
Screenshot_20210506-205102.jpg


I also remember the Tech telling me it ended up being the cheapest part of them all that actually fixed the pressure problem, so it may be the one-way valve that was to blame. Regardless, with fuel tanks in short supply - as I was told at the time - I felt it was cost effective to pay for everything to be refreshed, and be able to sleep at night because my LandCruiser sits in the garage. Next to the gas water heater...

Unfortunately, this is a case where going with the cheapest part and hoping it's good is problematic.

Adding; I also replaced the Charcoal Canister about a year prior with the AutoZone part, as OEM was NLA, and I dont believe it contributed to the problem at hand.
 
Joined
Nov 13, 2010
Messages
974
The vacuum control valve 90925-03192 may be it but I doubt that part was ever $2.50 though so it may have been some other valve @LongDuck was referring to. I would guess the FSM has a test to see if the VCV for evapl is working.

The part downstream or upstream just next the you listed costs 3.95 on partsouq called valve check no.1 9091710049 (labled check valve for evap in the FSM) that looks like a one way valve that only costs 3.95 on partsouq sounds more like it. On partsouq once you click on it is labled a fuel filter but it looks a lot more like a check valve though that you listed above and may be the actual part. For that price it might be reasonable to replace it.
 

Tedward

95 LC
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Cleveland OH
23285A in the partsouq pic
It's a small plastic, possibly possibly oragne in color, check valve in the vacumm tubing.
 
Joined
Sep 15, 2016
Messages
745
Location
Chattanooga, TN
Thanks for the replies,

I didn't test those out when I went in to replace lines/etc. but will go back in if/when I notice relevant fuel tank pressures. I often like to have the parts on the shelf to be ready when time allows the work so I appreciate the extra info.
 

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