We have had a slow leak in the top blue inflatable ring. This summer we had to put so much air in it so often, that the air plug cracked. Is there anyway to replace the air plug? I hate to throw the whole pool away for just that one crack.? Any help is greatly appreciated. Thank You

GREAT QUESTION.! OK now I see you have many posts and topic?
you need to have 1 post 1 top, (oil burner) do that use comment to the one post so it all stays as one.

YES ENGINES ARE AN AIR PUMP, HUGE.
EACH CYLINDER IS,
why not lead off with a real problem and all evidence first.
yes compression test can show 200PSI easy with 10:1 CR
both tests only prove the top 2 rings are good and cyl walls not scored hugely.( lead down at TDC)
no engine or maker told at all.

those other questions, about cracks
well gee , depends where the cracks are. and how bad they are.
freeze damaged water jackets? (you do know the machine chip pressure tests the block and head to find cracks not seen
and the cracks in heads can go anywhere wants. port, combustion chambers or water jacket to top if head OIL side. lifter side.

most times the leak-down test finds bad rings and is done at TDC.
so only finds cracks a TDC, unless you do tricky tests just after valves closed.

read the 100 point tests of of engine rebuild. it's huge. CHECK IT OUT FIRST.
oil consumption a question here?
oil control rings bad, or not seated or wallS with scoring
valve seals bad, are first to fail most time.
or valve stems guides so loose it beats the seals to *****.?
clogged PCV , and it burns more oil and leaks out seals.

the compression test is done , at 300RPM starter running.
warm/hot engine, not cold, all sparks out, W.O.T AND FULL BATTERY CHARGE ! factory manuals shows PSI to expect.
and is altitude dependent, (need chart ask)
AT THIS TIME THOSE PISTONS MOVE REAL FAST
AND WiLL IGNORE SOME SCORING AND CRACKS.
Due TO SWEPT SPEED ALONE.
and the test repeated with 1/2 teaspoon of oil, down spark hole if PSI jumps high rings are not seating.(for all the reasons)
SEE WHY LEAKDOWN FINDS MORE LEAKS ,IT'S SLOW

Wish I new what was the problem , at the beginning,
not told. what put you here, with no car stated, engine or size.

The air struts have a safety valve in them you would have had to crack the line and let the air slowly leak out

should return it --leak is usually the fill seal / gasket if unable to find a hole or seam

remove the O ring and clean it as well as the top and bottom housing. use an approved lube to treat the O ring (not vaseline). while applying lube, look for checks or cracks in the O ring. it doesnt take much for a leak.
when you are putting unit together, make sure the air release valve is open

They have problems with the air bag shocks leaking. The shocks typically have a large bladder bulit into them that will over time develop leaks causing the problem you describe. could be a damaged line to the shock but most often the shock. Start the car and run until it inflates. Stop the vehicle somewhere quiet then put your head by the top of the wheel that deflates. Listen and you should head an air leak. It usually requires replacement of the shock to fix.

Air leaking from the bottom of the gun (path of driver) indicates that cylinder seal orings are leaking (if without nails in gun the driver is slowly pushed down the cylinder when air is connected then cylinder seal is leaking ). Cylinder seal snaps on the top of the cylinder and should fit snug and have no cracks. Easy fix for cylinder ring. Remove head and pull out cylinder. Then remove the cylinder ring (part #n50015). Examine ring for cracks and replace as needed. Examine body of gun where spacer oring makes contact and sand fine scratches. Replace orings as needed. If air is leaking between body of the gun and nose casting, replace gaskets. Good luck.

Take a 12 X 12 piece of plastic wrap, wet the pool ring, slide the plastic sheet along until you see the air bubble appear, mark leak with marker pen. Use repair patch. I swear this is better than soapy water!

Soapy water never worked for me... Pour kids bubbles into a bowl and use a paint brush to spread the bubbles on the top ring. If there is a hole you'll see it begin to blow a bubble where the hole is.  patch with vinyl repair kit.

JOJO I FIND THAT THE SOAP YOU USE TO BLOW BUBBLES WITH WORKS THE BEST, BLOW THE RING UP REAL GOOD, AND GO SLOW. I HAVE USED CELLOPHANE TAPE TO FIX LEAKS ON MY WATERBED

Getting worse? Are you having to top up oil regularly? (oil over-filled and damaged hydraulic lifters / Piston rings failed / valve-stem seals decayed) Is the oil-cap gungy and yellow/brown froth? (Head gasket failed / head cracked / piston chamber cracked) If thats all ok, then its possible you have an air leak: Does car cut out when you slow down and stop? Does it hesitate when you accellerate from standstill in normal driving? Can you hear any whistling from the engine? Check for air leaks between the air flow meter to the head. I cant remember if this model has a throttle position sensor, but that might be dirty/faulty. Try spraying an electrical contact cleaner (not WD40. You can get contact cleaner from Maplin etc) into the throttle body (DO NOT SPRAY ANYTHING INTO THE AIR FLOW METER!). Finally, check the HT leads and the Coil pack. Good luck