After recently changing out an aftermarket SW fuel sending unit, I have not been able to get the new unit to seal. I used Permatex "Gray" gasket maker, which is supposed to be fuel resistant on both sides of the gasket. Was that the correct thing to do? I suspect that when the tank is full that the sealant is not able to resist the constant contact. Is there a better material to use? Or is the gasket supposed to be mounted dry?
Leak around fuel gauge sending unit
- Thread starter Toysx2
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There should be a rubber type gasket there. I've never run across any sealant at the sender. If you have to use sealant, I would try permatex aviation sealant. Let it tack up for a bit on both surfaces.
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That looks like a total mess. Maybe just replace the tank and sender with the right parts and you won't have a problem.
- Thread starter
- #5
Cruisermatt, I agree that the situation may not look the best, but as the original owner of this 1968 FJ40, all of the parts that are in the photo are the original or "right" parts that came in this vehicle. The conversion to a small block Chevy engine 40 years ago, necessitated a change in the gauges. I was replacing one Stewart Warner sending unit for another. Could not get the new one to seal. The screws are loose in the ring and straighten up when they are tightened....
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That sure is a long time. Longer then I have been alive so I can not relate to the wealth of memories I am sure you have. I still have my first LC my first car) and I hope to keep it forever as well.
However, your fuel tank is definitely modified. You can see the ring welded to it, actually a pretty clever repair.
Toyota still manufactures the tanks for these vehicles, here is what the sender looks like installed. I am away from my shop for the weekend or I would upload a good picture of the new tank I have in stock.
(Picture credit to City Racer)
However, your fuel tank is definitely modified. You can see the ring welded to it, actually a pretty clever repair.
Toyota still manufactures the tanks for these vehicles, here is what the sender looks like installed. I am away from my shop for the weekend or I would upload a good picture of the new tank I have in stock.
(Picture credit to City Racer)
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Thinking sentimentality may be an emotion that could get you exploded when it comes to gas tanks. I’d replace it.
Clean the metal surfaces with a wire brush. Apply a thin coat of Permatex® Form-A-Gasket® No.2 Sealant, 3 OZ | Permatex® - https://www.permatex.com/products/gasketing/gasket-coatings-sealants/gasket-sealants/permatex-form-a-gasket-no-2-sealant-3-oz/ to each surface. Assemble.
why the adaptor plate?
the OE one would have used the 5 screws to hold the sender to the tank.
can you not remove it and go straight to the tank as it is supposed to be mounted
- Thread starter
- #13
Thank you for the comment. As I have mentioned earlier, I am the original owner of this vehicle. Everything in the photo is original to the vehicle. Perhaps in other years, the sender was bolted directly to the tank? Would there be a difference between the flat surface of this ring for the rubber gasket to contact and the flat surface of the tank as far as the mounting of the sender?
- Thread starter
- #15
That is the reason for my question. It has been too many decades since I replaced the original sending unit with a Stewart Warner unit to remember whether the rubber gasket was supposed to be assembled with sealant or should seal without that added. If it should seal without, then I need another solution. If sealant is normally used, then I would like to know which one works best....
I beg to differ,
THAT IS NOT TOYOTA ENGINEERING
maybe when the first aftermarket sender was installed, is when this contraption appeared
who did the V8 install years ago?
do the studs twist/rotate?
no sealant should be used/required with a good rubber seal
Yeap this.
No way would toyota put two points of potential failure on top of the tank like that.
That is 100% an adapter to fit the after market sending unit.
- Thread starter
- #18
Thanks again, especially for your comment that no sealant should be used. Because of your definitive statement that the plate is not Toyota Engineering, I did a bit more investigating. It appears that the plate is a commercially available "contraption" to adapt Toyota's JIS standard used in the spacing of their mounting screws on the Toyota gas tank to the SAE standard spacing used by Stewart Warner and most other aftermarket sending unit manufacturers. I have no recollection of where or when I acquired this adapter. It appears that for my application that I should try and use the plate. I have just discovered a discussion of this topic on this forum from back in 2009. One solution for the leakage seemed to be to double up on the thickness of the gasket......
What yr 40 do you have?
OEM Fuel Tank Sending Unit for '66 to '72 Land Cruiser FJ40 FJ45
OEM fuel tank sending unit for '66 to 9/'72 Land Cruiser 40 Series. Compatible with F engine. Gasket and screws are available separately. Technical note: This sender isn't "resistive". It works like an oil pressure sender, with a bimetal points type regulator it it. The float moves the contacts...
www.cityracerllc.com