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Looking for some ideas.....trying to replace my fuel gauge sender and all the screws are spinning. I tried the old pry underneath trick and no go, they are all still in place. I don't want to cut the heads off (sparks and gas fumes don't mix!) as I think if there is a nut on the bottom it and the shaft will drop into the gas tank. Been looking thru the TM's and they don't seem to be any help with this.
I also tried to remove the larger access hatch next to it, but I have several screws that have buggered heads courtesy of a previous (before me) attempt.

WarrenD wrote:Looking for some ideas.....trying to replace my fuel gauge sender and all the screws are spinning. I tried the old pry underneath trick and no go, they are all still in place. I don't want to cut the heads off (sparks and gas fumes don't mix!) as I think if there is a nut on the bottom it and the shaft will drop into the gas tank. Been looking thru the TM's and they don't seem to be any help with this.
I also tried to remove the larger access hatch next to it, but I have several screws that have buggered heads courtesy of a previous (before me) attempt.

Would you be able to get a claw hammer underneath the screw head and lift while unscrewing?

Sawing the heads off is the answer. If you are concerned about the fuel, drain the tank and purge it first.

Stu, already tried that, seems like there is a nut inside the tank that is just spinning.
Thanks, Cuz, I was afraid of that. I may look into a "new" tank, I'll have to see. Not sure what shape this one is in, I do smell gas quite often and I know the E10 fuel wreaks havoc on the metal tanks. I may end up dropping this one, have it cleaned and sealed.

GOOD MORNING, Why would you think that E10 damages metal tanks?? Are not most auto fuel tanks metal?? I do know that it destroys fiberglass tanks in boats. The alcohol eats at the resin and they start to leak.. I have had my M for three years now, with the original metal tank. NO PROBLEMS. the alcohol did eat an original rubber hose.
BOB

Bob, My understanding is that the ethanol in the gas absorbs water (like dry gas used to in the old days, allowing the water to be "burned" with the gas during combustion). With many of us, our trucks sit for periods of time between uses which can result in the water reacting with the metal of the tank. Not sure what they use for gas tanks these days, I think they are mostly aluminum.
Thanks for the heads up on the rubber, I'll have to check my filler as according to a diagram there is a section of rubber connecting it to the tank.

The alcohol components do absorb moisture and keep it suspended so it will not settle on the tank surfaces and corrode it. Your concerns are not necessary. It is the rubber parts in your fuel system you should be concerned for.

The same error in beliefs exist with brake fluids. The DOT 3 and 4 will absorb moisture thus preventing corrosion caused by moisture settling to the lower parts of the system. DOT 5 (silicone) does not absorb moisture and it does settle to the lower parts of the system and it does cause corrosion.

Both Ethanol fuels and DOT 3/4 brake fluids have a finite limit on how much moisture they can absorb and when that point is reached either will allow additional moisture to settle. That is why they must be flushed and replaced at least every two years.

dry gas used to in the old days

Actually up through the 80's gas did not have a tendency to absorb moisture. It settled to the bottom of the system. In the winter we added fuel ant-ice fluids and treatments (gas line anti-freeze etc.) which were nothing more than alcohol products and that alcohol absorbed the moisture.

Most fuel tanks today are plastic.

Gonna be a tall order w/o sparks of some kind. I had to tack one of my pick-up cover "studs" in place after the radiator shop told me they used studs when actually they ran some small stove bolts up from underneath and I stripped it trying to remove it.

Good luck with it-let us know how it turns out.
Gary

cuz wrote:The alcohol components do absorb moisture and keep it suspended so it will not settle on the tank surfaces and corrode it. Your concerns are not necessary. It is the rubber parts in your fuel system you should be concerned for.

The same error in beliefs exist with brake fluids. The DOT 3 and 4 will absorb moisture thus preventing corrosion caused by moisture settling to the lower parts of the system. DOT 5 (silicone) does not absorb moisture and it does settle to the lower parts of the system and it does cause corrosion.

Interesting.

From everything that I've read previously, because DOT5 is not hygroscopic, it does not pull moisture through the rubber brake hoses into the brake system. Compared to DOT3 or DOT4, DOT5 significantly reduces water in brake fluid. Water will indeed settle to the low parts of a DOT5 system, but the DOT5 means that very little water will be in the system to begin with versus a DOT3 or DOT4 system.

Similarly, I understood that the hygroscopic properties of DOT3 and DOT4 did not prevent the moisture from attacking steel brake lines and cylinders. Holding the water in suspension in the brake fluid supposedly did not prevent contact with the steel components.

Interesting.

From everything that I've read previously, because DOT5 is not hygroscopic, it does not pull moisture through the rubber brake hoses into the brake system. Compared to DOT3 or DOT4, DOT5 significantly reduces water in brake fluid. Water will indeed settle to the low parts of a DOT5 system, but the DOT5 means that very little water will be in the system to begin with versus a DOT3 or DOT4 system.

Similarly, I understood that the hygroscopic properties of DOT3 and DOT4 did not prevent the moisture from attacking steel brake lines and cylinders. Holding the water in suspension in the brake fluid supposedly did not prevent contact with the steel components.

Trying to keep this basic .

DOT 3/4 suspends the water and yes it can come in contact with the steel parts but it is a dynamic contact not static puddling of water. Let's not delve into hose linings and the minute amounts of moisture that can find it's way thru there. Many modern hose linings are available that will stop this. Let's just consider the fact that the master cylinder is vented to the atmosphere and the greatest amount of water enters there with all fluids used. Next greatest source of water is introducing fluids from previously opened containers. Giving DOT5 credit for curtailing moisture entry through hose linings is really not that measurable. The 2 year flush and fill standard prevents any long term issues developing from the use of either fluid.

The bottom line in choosing brake fluids for the hobbyist are:

1-Paint damage + for 5
2-Moisture issues Both have issues but over the long term the dot fluid left in there longest will have the most problems.
3-Heat + for 4 (Dot 5 has never done well around heat. Weather from disc brakes or exhaust manifolds close to the fluid)
4-Good Hard pedal after bleeding + for 3/4 (5 will always feel softer due to the entrapped air )

cuz wrote: The bottom line in choosing brake fluids for the hobbyist are:

1-Paint damage + for 5
2-Moisture issues Both have issues but over the long term the dot fluid left in there longest will have the most problems.
3-Heat + for 4 (Dot 5 has never done well around heat. Weather from disc brakes or exhaust manifolds close to the fluid)
4-Good Hard pedal after bleeding + for 3/4 (5 will always feel softer due to the entrapped air )

Perhaps we should move this discussion of brake fluids to a new topic?

My understanding of the DOT grading system is that the number indicates relative boiling points. DOT4 has a higher boiling point than DOT3, DOT5 is higher than DOT4, and DOT5.1 has the highest boiling point, which is probably why it's specified for ABS systems.

We used DOT5 (and now DOT5.1) on Harley-Davidson motorcycles for years, and the rear calipers were very close to the exhaust system on some models; those mufflers were way too hot to touch, and hot enough to melt boot soles. We never had a problem getting a hard lever or pedal (provided that the brake system was in good condition) with the DOT5.

Harleys aren't jeeps!

Why do you suppose Corvette only experiment one year with DOT5 in the early 80's?

By the way it is not DOT5's boiling point at the crux of the problem. It is the heating of the encapsulated air in the silicon fluid that expands and creates a softer and softer pedal.

There's plenty written on this topic by the pro's and I've read most of it and dealt with DOT5 in most of the different vehicle types and MY TAKE on it is as posted above. Your take on it is as posted above.

So the best deal here all around is to agree that we don't agree and neither mind is going to change!