Fuel level when Winterizing
Race Director
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From: SE WI
Thread Starter
Team Owner
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From: Chirper Island
Try and tell that to the C6 crowd. I did yesterday, and was told I was confused. 
None of them are having it, because it contradicts everything they ever thought was true.
The senders are not dissimilar, and the C6 has plenty of history with the sender fouling and the same issue with having to drop the rear end to replace to the tune of big $.
None of them are having it, because it contradicts everything they ever thought was true.The senders are not dissimilar, and the C6 has plenty of history with the sender fouling and the same issue with having to drop the rear end to replace to the tune of big $.
E-Ray, 3LZ, ZER, LIFT
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From: NE South Carolina
^^^
Then also no concern about corrosion! So the old "keep it filled to eliminate moisture" is an "old rule for old tanks!" Frankly with sealed tank systems and no vents wonder if the "old approach is all based on old situations?"
Then also no concern about corrosion! So the old "keep it filled to eliminate moisture" is an "old rule for old tanks!" Frankly with sealed tank systems and no vents wonder if the "old approach is all based on old situations?"
Last edited by JerryU; Nov 7, 2018 at 09:59 PM.
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From: Guelph, Ontario
The C5 and C6 can also benefit from having it at a 1/4 tank or less, as they have basically the same design for the tank and sensor.
Last edited by Patman; Nov 8, 2018 at 07:40 AM.
Melting Slicks
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Does not matter how much fuel you leave in the tank. Make sure to use some type of fuel stabilizer and if you are worried about the sending unit throw a bottle of techron in it. Some guys like to store their cars with none ethanol fuel and that's fine but they need to add some isopropyl fuel treatment to combat moisture in the fuel. Storing with fuel with ethanol there is no problem with moisture but I like to add seafoam or other fuel additive to treat and stabilize the fuel.
I have high performance snowmobiles and all I do is add stabilizer and run my sleds till it's throughout the fuel system and into the injectors before storage. In the Fall they start up like they were never stored and run perfect. High reving turbo 4 stroke snowmobile engines are more sensitive than any automobile engine and I have never had an issue storing them this way.
I have high performance snowmobiles and all I do is add stabilizer and run my sleds till it's throughout the fuel system and into the injectors before storage. In the Fall they start up like they were never stored and run perfect. High reving turbo 4 stroke snowmobile engines are more sensitive than any automobile engine and I have never had an issue storing them this way.
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Correct, Paul services my C7 and always states in his seminars that GM recommends 1/4 or less fuel in the car when storing. The cost of dropping the drive train and replacing the sensor is very expensive, also with the tanks being made of plastic there is less of a chance for condensation. On my last tank of gas I treat with Stabil and Techron and run it down. I have done it this way now for three years with no problem.
I personally heard Paul state this at a seminar in Bowling Green. That is what I've done with my Vettes since.
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.ALL my Mercedes Benz diesels for decades use steel fuel tanks. As is my diesel RV's 55-gallon steel fuel tank. These are to be stored with FULL TANKS of diesel fuel, WITH Power Service an moisture dissipating additive added. Yes, steel fuel tank insides are known to accumulate rust!
Last edited by Skid Row Joe; Nov 8, 2018 at 05:41 PM.
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From: Milwaukee WI
All of this discussion speaks of fuel tanks and senders in singular terms. C7's and earlier Corvettes have two fuel tanks and two fuel level senders. I lean toward Bill Dearborn's statements in that 1/4 full on the fuel gauge does not mean 1/4 in each tank.
We need a better description of the twin fuel tank operation detail for an informed opinion on this topic.
We need a better description of the twin fuel tank operation detail for an informed opinion on this topic.
Thread Starter
Team Owner
Joined: Apr 2013
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From: Chirper Island
All of this discussion speaks of fuel tanks and senders in singular terms. C7's and earlier Corvettes have two fuel tanks and two fuel level senders. I lean toward Bill Dearborn's statements in that 1/4 full on the fuel gauge does not mean 1/4 in each tank.
We need a better description of the twin fuel tank operation detail for an informed opinion on this topic.
We need a better description of the twin fuel tank operation detail for an informed opinion on this topic.
From what I understand, our C7 tanks have a "jet-siphon" which equalizes the fuel in each tank (when running) so they drain equally, unlike the C6, which has only the Venturi siphon to fill the right side, which then empties first.
Understanding the differences (and similarities) between the C6 an C7 tanks is the reason I started the thread. I know It may not seem that way, but... I do post in both forums, and I need clarification sometimes.
Sometimes, I am a doofus.
All info is welcome.
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From: SE WI
Try and tell that to the C6 crowd. I did yesterday, and was told I was confused. None of them are having it, because it contradicts everything they ever thought was true.
The senders are not dissimilar, and the C6 has plenty of history with the sender fouling and the same issue with having to drop the rear end to replace to the tune of big $.
None of them are having it, because it contradicts everything they ever thought was true.The senders are not dissimilar, and the C6 has plenty of history with the sender fouling and the same issue with having to drop the rear end to replace to the tune of big $.
Team Owner
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St. Jude Donor '13
The problem with deciding how much fuel to keep in the tank is that we don't have any good data collection system to see if one method causes more problems than the other.
We now have been driving modern (C5-6-6-7) Corvettes for 17 years/230,000 miles. We often store the car for 2-3 months during the winter.
The tank is normally refilled whenever the level gets below 1/2 in normal driving, and filled up before storage. So our sender is immersed in fuel 99% of the time. We always use Top Tier gas, and once per year I add a half-bottle of the GM Fuel Treatment (Techron).
So far, we have not had any problems at all with the fuel gauge. But four cars are not a definitive sample, and other people using similar technique do have problems.
We now have been driving modern (C5-6-6-7) Corvettes for 17 years/230,000 miles. We often store the car for 2-3 months during the winter.
The tank is normally refilled whenever the level gets below 1/2 in normal driving, and filled up before storage. So our sender is immersed in fuel 99% of the time. We always use Top Tier gas, and once per year I add a half-bottle of the GM Fuel Treatment (Techron).
So far, we have not had any problems at all with the fuel gauge. But four cars are not a definitive sample, and other people using similar technique do have problems.
Race Director
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From: SE WI
The problem with deciding how much fuel to keep in the tank is that we don't have any good data collection system to see if one method causes more problems than the other.
We now have been driving modern (C5-6-6-7) Corvettes for 17 years/230,000 miles. We often store the car for 2-3 months during the winter.
The tank is normally refilled whenever the level gets below 1/2 in normal driving, and filled up before storage. So our sender is immersed in fuel 99% of the time. We always use Top Tier gas, and once per year I add a half-bottle of the GM Fuel Treatment (Techron).
So far, we have not had any problems at all with the fuel gauge. But four cars are not a definitive sample, and other people using similar technique do have problems.
We now have been driving modern (C5-6-6-7) Corvettes for 17 years/230,000 miles. We often store the car for 2-3 months during the winter.
The tank is normally refilled whenever the level gets below 1/2 in normal driving, and filled up before storage. So our sender is immersed in fuel 99% of the time. We always use Top Tier gas, and once per year I add a half-bottle of the GM Fuel Treatment (Techron).
So far, we have not had any problems at all with the fuel gauge. But four cars are not a definitive sample, and other people using similar technique do have problems.
Last edited by Zjoe6; Nov 10, 2018 at 12:20 PM.
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From: Lake Havasu City Arizona
The problem with deciding how much fuel to keep in the tank is that we don't have any good data collection system to see if one method causes more problems than the other.
We now have been driving modern (C5-6-6-7) Corvettes for 17 years/230,000 miles. We often store the car for 2-3 months during the winter.
The tank is normally refilled whenever the level gets below 1/2 in normal driving, and filled up before storage. So our sender is immersed in fuel 99% of the time. We always use Top Tier gas, and once per year I add a half-bottle of the GM Fuel Treatment (Techron).
So far, we have not had any problems at all with the fuel gauge. But four cars are not a definitive sample, and other people using similar technique do have problems.
We now have been driving modern (C5-6-6-7) Corvettes for 17 years/230,000 miles. We often store the car for 2-3 months during the winter.
The tank is normally refilled whenever the level gets below 1/2 in normal driving, and filled up before storage. So our sender is immersed in fuel 99% of the time. We always use Top Tier gas, and once per year I add a half-bottle of the GM Fuel Treatment (Techron).
So far, we have not had any problems at all with the fuel gauge. But four cars are not a definitive sample, and other people using similar technique do have problems.
Race Director
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From: SE WI
Yes, but when you are driving it the fuel is constantly sloshing around the sending unit. That keeps the sulfur from building up. As far as storing the Corvette with a full tank, etc., that doesn't guarantee the sending unit will become corroded, but it does increase the chances of that happening.
Team Owner
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St. Jude Donor '13
However, I used our C5 as my DD through five Chicago winters, installed the big knobby Goodyear winter (not A/S) runflats and did pretty well. When traded at 5 yrs/66k miles, it looked just like any other summer-only Corvette. So maybe I'm being too careful with our C7.
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