Thank you Jeremy for that very useful info, especially as it is so different from what we learned and practiced for decades. Paul Koerner is the best GM Master Corvette Technician, and I follow all of his suggestions.

Very, VERY useful post Jag!

 

Thank you very much Jeremy!

 

Interesting, but there's something here I don't understand. If the fuel level sender is halfway up the tank, how does the system tell the difference between 1/2 tank, 1/4 tank, 1/8 tank, etc.? It would seem once the fuel got below the sender the system would show empty.

Something doesn't make sense? Anyone reading this have a shop manual that shows the sender location?

 

Interesting question Meyer and i would like to see more information about this also. As a guess it could use the sensor from mid-level up as a calibration point/notification of refill/reset and below that the gauge indication is driven by calculated fuel remaining through data generated from the fuel flow transducer.

 

Last winter I upped the PSI by 5 LBS for winter. Is this a good practice as well?

Please note, I will not put my car on any kind of blocks/jacks to take pressure off the tires.

Gus

 

I did not see this thread last year but always good to discuss these things before winter arrives. I usually leave my Corvettes either in the garage or, more recently, up on the top of the lift for roughly four months without driving them. On tire pressure, a friend of mine who runs a restoration/refurbishment shop for classic and specialty cars and stores cars in the winters (he cared for a dozen of Michael Jordon's cars for about a decade) told me he runs tire pressures up to 60 psi for winter storage to prevent flat spotting. That sounded a little high to me but I tried it with my ZR-1s and it did minimize flat spotting. However in the last year I owned one, I developed a slow leak that the techs at Costco (where I had gotten my tires) diagnosed it as a bad valve and replaced it for free. When I mentioned my storage approach the shop manager said that officially tire valves are only warranted up to 40 psi. Since then I have put the pressures up to 50 psi without any issues and minimal flat spotting that goes away with a little driving. On fuel I have always stored with a full tank and never used a fuel stabilizer. Some people swear by stabilizers, some don't like using them. I did this for 20+ years and never had a fuel system issue in my ZR-1s or my Z06. Always use a top tier gasoline.

I will have to do some more research on the question of whether to fill only to 1/4 tank. I noticed this on Wikipedia's page on top tier gasoline: "Certain forms of sulfur that refiners or pipelines may leave in finished gasoline, such as mercaptans and hydrogen sulfide, can contaminate fuel sending units and lead to erratic dashboard fuel gauge readings, which may be expensive to repair. The regular use of a TOP TIER Detergent Gasoline can prevent this from occurring. However, this problem has become less common as manufacturers are now making these units with improved alloys that are less affected by these forms of sulfur." Has GM avoided using the better alloys in their sending units? --Bob

 

I try to drive my car throughout the winter every couple weeks when the roads are dry. Any issues concerning fuel level under these conditions? I usually fill up when my gauge reaches the halfway point.

 

No issues with your tank being anywhere from almost empty to completely full if you drive is at least monthly according to Paul Koerner. [Paul is, IMO, Corvette's best Master Tech; he is the one that presents the C7 (and earlier gen) technical Corvette problem solving seminars at the key NCM annual function s]. Your gasoline, as it is sloshing around when car car is moving, will not allow sediments to build up on the sensors. It is when your car is filled up beyond a 1/4 of a tank and then sits for a month, that the impurities (and perhaps even the basic components of gas), can build up on the sensors.

I am completely changing my winter storage plan as a result of Jag learning this info from Paul.

 

Quick question on the issue of storing. My new garage is smaller than my old garage because the steps are on the side of the garage instead of the back of the garage. So its hard ti get both of my vehicles in the garage. So I was going to use these tire dollies to allow me to just push my vette against the walk when storing it. The question is, can my vette tires rest on these dollies without damaging the tires? Normally my vette sitson matts in the garage

 

These are the pictures

 

Those are 9" wide - not wide enough for our C7s.

I have these from Harbor Freight that I use with my '68 and '91:

​

They work for tires up to 13-9/16 in. (345mm) wide.

 

Those are 9" wide - not wide enough for our C7s.

I have these from Harbor Freight that I use with my '68 and '91:

View attachment 73090​

They work for tires up to 13-9/16 in. (345mm) wide.

I just purchased a set of these for Ruby. Thanks for the info. I decided on these so I can lift the car and then carefully move it up against the wall, leaving more room for my wife's soon to be snow and salt covered Jeep Cherokee parking next to it all winter. Thanks everyone else for the info about storing. Even with these dollies, I will still up the psi a bit to avoid flat spots and make sure the car is at 1/4 tank before I say good night for a few months. Now if I could just convince my boss that I need to hibernate over the winter like my car and come back in spring when the driving weather is better. That or just move to a warmer climate so I can drive this for more of the year.

 

I would feel much better about those Mobius pictured, that distribute the load evenly, than those which put all the weight on two very narrow cylinders.

 

I totally agree!

 

I suppose another good reason for storing with only 1/4 tank of fuel is, when you wake the car up in Spring, you stop down at the gas station and fill it up. You now have a tank of fuel that is 75% fresh fuel, instead of driving around burning off a tank of fuel that is maybe 4 or 5 months old.

 

If a bottle of Chevron system cleaner cleans the contacts, why not continue to store with a full tank, just to be doubly sure of avoiding condensation? Why tax the charcoal filter and test the double filler pipe if your storage location/facility creates a lot of weather variations? Then simply add a can of it in the Spring?

 

I have a vague recollection of seeing some drive-on tire dollies once upon a time, but Google turns up nothing. The only hydraulic lift ones I see online are similar to the first ones you posted.

 

If you plan to store your C7 for longer than one month, Paul emphasizes the following points. Review your owner's manual for more storage recommendations (battery tender, ect.).

- Store newer Generation (4 through 7) with 1/4 tank of gas.

- Use fuel stabilizer if storing for longer than one month at a time.

- Change oil before storage

The reason for only storing with 1/4 tank of gas has to do with the location of the fuel sending unit. In the C7, the fuel sending units are half way up inside each of the two tanks. Sulfur in the gasoline can coat the fuel level sensors, causing the fuel gauge to become inoperative. The reason that this does not happen when you are regularly driving the car is that movement of the gas in the tanks keeps the contacts clear. In order to clean the contacts, use a 20 ounce bottle of Chevron Techron Fuel System Cleaner (Auto Zone, etc.).

The old reasons for storing with a full tank of gas no longer apply with the C7. The double sealed fuel filler neck and the charcoal canister on the other side of the tank prevent moisture build up from taking place.

Very interesting. I don't store my car but do have a concern about suffer build-up on the fuel sender because of reports of problems!

Assume the float hangs below the rheostat (or whatever is used to send level signals) like most senders and it is half way up the tanks. Since I do not always use Top Tier have been using the GM recommended product mentioned in the Owner's Manual ( probably Techron as it comes in the same appearance bottle and has a similar SDS) as recommended at every oil change. Thought it may also help the injectors. Sounds like I'd also be better off keeping the tank under half full! :semi-twins:

 

Some FYI here:

Some personal experience with wheel dollies, yes they do work, however, once that 3200 lbs+ are on the dollies, I strongly advise that you do not try to move the car by pushing on any panel on the vehicle, especially a Vette. You have a good chance of breaking something. I tried that once on my '75, and started to hear a little tress noise on the fender....oops...stopped that immediately. Since I didn't have chrome bumpers, I had to push/pull on the tires/wheels.......that way you won't break anything. And if you're by yourself.......I had to put my back into the wheel to get it to move.....what a pain in the butt. Also, if you don't have a completely smooth surfaced floor.....fagettaboutit, it ain't moving.

I'm talking about the little wheeled dollies at the Harbor Freight level now, I'm sure there are better quality ones available.

 

"In order to clean the contacts, use a 20 ounce bottle of Chevron Techron Fuel System Cleaner (Auto Zone, etc.)."

If storing with only 1/4 tank of gas, should we really be using the entire 20oz bottle of fuel system cleaner? Usually one bottle covers up to 20 gallons of gas.

 

I was under the impression that the idea was, for those who put their cars into winter storage, to fill the tank up in the spring, and, at that time, add the Chevron Techron Fuel System Cleaner. Then just drive normally until you use that whole tank of fuel+Chevron Techron Fuel System Cleaner.

 

For many fuel additives, the manufactured date is given by a 5 digit code - the first two digits reflect the year and the remaining three digits reflect the day of the year.

In the example below, this fuel stabilizer was produced in 2012, on the 272nd day of the year. Sta-bil (as one example) has a 2 year shelf-life, after the bottle has been opened. After that, toss it out.

​

 

Quick question. If I'm starting and moving the car in and out of the garage all winter, does the 1/4 tank fill apply? I don't drive it typically because of the North East brine they put on the roads, but I do move it in and out of the garage, rev it slightly and let it idle then pull it back in the warm garage. I appreciate the input!

 

Please read the linked thread, for running one's car by idling and reving can do other kinds of harm to it. The generally recommended way to keep your car stored for winter in terms of running the motor is to take is for at least 30 minute drive monthly to get all fluids up to temp, or to not start it at all.

http://www.stingrayforums.com/forum/stingray-corvette-discussions/1762-c7-cold-winter-storage.html

 

If you're doing that because you think it's better to run the car for a few minutes than let it sit, just don't!

Unless you run it long enough to get the engine, coolant and oil to normal operating temps, all you're doing is letting condensation build up in the engine. That condensation ends up as water in the oil. Bad for the engine, bad for the oil. It's far better to not start the car at all if you're not actually going to drive it long enough to get everything thoroughly warmed up.

If you're moving it because you have to get a snowblower out, or something like that, my suggestion would be to rearrange the garage so you don't need to do that.

To answer your question, though, I think the answer is it depends on how often you're moving the car. It's reported that the problem with the fuel senders doesn't occur in normal use because of the regular movement of fuel around the sender. If you're only moving the car infrequently, I don't think that would be enough to prevent issues.

 

My old car gets very little use these days. It hadn't been driven in quite some time. When I finally drove it again, the fuel gauge was went crazy.

The gauge showed a little more than 1/2 of a tank at the start of the drive (which was probably about right), but shortly into the drive, the gauge went to almost empty. Then it started slowly going up and down as I would accelerate and/or go around curves.

I put a little gas in it, drove it hard around curves (to get it to slosh the gas around in the tank), put a little bit more gas in, drove and sloshed it some more, et cetera. After a few days, it seemed to work properly again.

It had been sitting around for maybe two and a half months or so before it acted up that way.

What is the point of my post? The sloshing of the gas in the tank is the key to preventing this from happening, and also, at least in my case, it seems as if the sloshing of the gas in the tank was the cure as well.

 

What is the point of my post? The sloshing of the gas in the tank is the key to preventing this from happening, and also, at least in my case, it seems as if the sloshing of the gas in the tank was the cure as well.

Excellent justification for some spirited driving on my twisty two lane roads!! I'm keeping my gas gauge from acting up!!

 

[slightly off topic]
Has anyone regretted putting dryer sheets inside the car? Does the smell linger even if you put it on a plate? I dont particularly like the smell.

 

I use plenty of dryer sheets both in Florida and in Wisconsin…with no issues or oder that lingers.:smile-new:

 

ok cool. what about moth balls?!

 

Never use them…can't stand the smell.

 

With winter approaching (yuck!), I'd thought it might be a good idea to revive this thread, especially for our newer northern members. The biggest change (and surprise) for the C7 is to fill your gas tank only to the 1/4 mark when you put it into storage. Also a lot of good info here on oil changes, tire pressure and battery maintenance.

 

Yes. You don't want to contaminate the sending unit. The gas settles against it in storage. No effect though with full tanks when driving the car because the fuel is constantly sloshing around the sending unit, thus cannot stick long enough to contaminate it. Now someone may post that it never hurt their car, but odds of contamination are significantly more likely for contamination.

 

I thought if you left the tank below full you allowed space for condensation, but I live in California and drive my ride weekly.