MW 500 water heater electric glass lined in leaking 1+ cup of water daily and getting worse what if anything can I do to fix problem

if not the inlet or outlet connections-the heating elements or relief valve then most likely have a damaged tank and most likely need a replacement

Replacing a water heater is no very difficult if you follow the steps.
1. If it is electric turn of the breaker and check to be sure it is the right breaker. If it is gas turn off the valve close to the water heater.
2. Turn off both the hot water and cold water valves
3. Drain all water out of the heater.
4. Disconnect the electric wiring if electric and if gas disconnect the gas line.
5. Disconnect both water lines which may have to be cut depending on how they are connected.
6. Now you can remove the water heater and discard.
7. Place new heater where old one was removed and reconnect both water lines and be sure you have a new pressure valve installed on the water heater.
8. At this point you can turn on water and check for leaks. you should also open a hot water faucet to purge the air out.
9. If no leaks go ahead and hook up the electric or gas lines and if gas is used turn it on and check for leaks using a leak detector or a spray bottle of soapy water and look for bubbles. If no leaks you can go ahead and light the heater according to its instructions.
10. If electric is used turn it on.
11. Take a long hot shower.

Tank is rusted out:
Replace tank
http://waterheatertimer.org/Leaking-water-heater.html

Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

There is no way to fix a leaking water heater to date it is glass lined

Do not spend 500 on plumber to determine that condensate drain was not installed properly on vent line, and that acidic water from combustion by-product has been dripping down into tankless and burning hole through the special-alloy heat exchanger instead of going down into floor drain and corroding your plumbing pipes.
Do not spend hours fulfilling the required monthly and yearly maintenance, or spend money on service call each year to get the burner cleaned and gas pressure checked on your tankless computer that heats water...
Instead, fix any tankless problem, any brand tankless, same day do-it-yourself for $385, by replacing 1 part: the whole thing:http://waterheatertimer.org/How-to-install-gas-water-heater.html
Do not install tankless.
Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

You have 2 problems with several possible causes:
You have 10-year-old electric water heater that was reinstalled after falling down, and doesn't heat the water.
And you have no hot or cold water pressure, and no pipes are leaking.

1) First problem is lack of water pressure throughout house.
Turn on outdoor spigot nearest to water meter.
This spigot will tell you if problem is inside the house or between the house and meter.
If spigot runs full force, then you probably have clogged pipe where water heater connects to main cold line, or the main shut off valve got clogged with sediment that broke off inside the pipe when you were working on water heater.
Open and close shut off valve to see if that helps. Then disassemble pipes and track back the problem. Put pressure gauge on water heater drain valve to watch pressure drop when turning on indoor faucet.
Read following information:
http://waterheatertimer.org/Low-hot-water-pressure.html

Water heater doesn't work:
Test across wires at top of heater to see if you are getting correct voltage:
If tank is receiving correct voltage, then no hot water puts suspicion on upper element or upper thermostat, or both.
Open following link for electric water heater troubleshoot steps:
http://waterheatertimer.org/How-to-troubleshoot-electric-water-heater.html

You have 240volt electric water heater
Check both elements for leaking.
Check top of tank for leaking pipes.

If water heater is leaking from side of tank, then tank is rusted out and could rupture.
This tank must be replaced.
http://waterheatertimer.org/Water-at-bottom-of-water-heater.html
My friend welded his tank to get more life out of tank, but he assumed the risk.

Hot water heaters are under pressure from heated water which expands.
If tank ruptures, water will flood out of tank and water will run until shut-off is turned OFF.
This causes major damage inside home.

Protect yourself first, and then let's talk more.
1) Turn off water at shut off located on cold water line above tank.
2) Turn off power to water heater:
Gas heater, rotate valve to 'pilot' so pilot is lit but burner does not turn ON.
Electric heater, turn off circuit breaker.
3) Open tub spout on hot side and let run a bit to relieve pressure.
4) Now your property is safe.

You can limp along with failed heater if leak is slow.
Turn heater ON when you need hot water.
Typical Gas heater makes 41 gallons hot water per hour.
Typical Electric heater makes 21 gallons hot water.
Shower uses 5-9 gallons hot water, bath uses 12-14 gallons hot water.
http://waterheatertimer.org/images/Water-heater-reference-guide-2.jpg

If you are going to install heater yourself:
Look at label on side of old tank to identify size and particulars.
I buy ordinary heaters from Lowes and Home Depot and always buy scratch-n-dent models when possible, because superficial damage to outer tank does not lower lifespan of heaters I have installed.
Buy same size heater if it worked fine before.
Buy new flexible water connectors.
Set water heater in drip pan.
Offer 10% less than price shown. Make them deal with you. Shop Ace hardware, Lowes, Home Depot. Kick the tires since you have a bit of time.

I know you have electric heater, but many folks read these answers, so I include info on gas too.
#1 rule) tankless heaters are a rich-man's toy, because tankless will never pay you back, and will become major money pit if you encounter 1 repair. Electric tankless heaters require larger electric service box. Gas tankless require larger gas line (larger gas line, more gas consumption, bigger bill unless you cut consumption)
2) How to install gas heater:
http://waterheatertimer.org/How-to-replace-gas-water-heater.html
3) How to install electric heater:
Read link above because many of same steps apply to electric.
The difference with electric, is turn off power, disconnect wires, and reconnect wires exactly like before. Set electric heater directly on insulated surface like dense blue styrafoam. Cut styrafoam in circle so it fits inside dip pan. Wrap entire electric heater with insulation blanket, except don't cover TP valve.
4) Connect bare copper jumper wire between hot and cold pipes to prevent stray current corrosion which will shorten life of tank. Make sure cold water line is grounded.

Also read:
http://waterheatertimer.org/9-ways-to-save-with-water-heater.html

Add a comment for more free assistance.
Also take advantage of fixya phone service.
For a price, fixya expert speaks to you via phone about any do-it-yourself problem.

Check the relief valve,drain and element's,water lines to make sure that they are not the source of the leak. If the tank is leaking you may be able to fix it for now.

The tank depending on condition of the tank if it is pretty sound. Clean up the area of the hole with sand paper. Go to any hardware store and get a JB Weld two part kit. JB Weld will fix almost anything . You can go to www.jbweldit.com for more information about this product. I wish you well and hope this will fix it for you.

mfr date 10/87

Maybe you want to think about getting a tankless heater.The gad unit works real good.But the electric water heater i want to think you should check the thermostate.Maybe it is struck and not cutting off every time.