I know I am prone to over-watering, so whenever I see yellowing, I suspect I am watering too much too frequently. Cut back on water and give the plant a dose of chelated iron and see if it perks up. It does look like it's in a hot spot so it could be heat. Have you mulched around the plant? That could help; just make sure you don't heap the mulch up around the trunk.

I have a question
What kind of watering stake are you referring too?
If it is, what I think it is 36" down in the ground is pretty deep and if the trees have not grown much the root system is not that deep. Try using a piece of old rebar to check if you are actually watering the roots or below them also use this method to see if they need watering(soft ground- ok, hardground- water)( for them 2ft down should do it for now)
If the water is ok then get a shovel or spade and dig down and see what is going on down there try not to disturb the roots. They kind of sound stunted. Could be they are in basically a cement hole. I would do this right away before the tree gets worse. Until you look at the watering and soil situation and are satisfied, I would not fertilize with anything. Our last house we had over 15 different citrus trees and Meyers were our favorite. Good luck will check back later
PS @ 3 years old the tree s/b 4ft high or better

Here's a bit about using chelated iron that you might use. Citrus likes acidic soil, but most of us here have alkaline soil. Here's a question or two for you? How old is your subdivision? Was it built on former bare desert or agricultural land? Is it hard-packed soil or loose and loamy? I really doubt that it's soft soil, but you never know. I agree with campv that soil tests are really useful, but I've never gotten around to that. You can buy inexpensive home test kits, though, and that could give you some useful info.

Here is a link that might be useful: chelated iron

The soil is very hard and I have to usually use a pick and a shovel to break through the layers when digging. When i was surface watering it would not seep through very well. The core of the root ball was about 1 foot below the surface when planted 3 years ago and I'm watering from 2-3 feet down until the water level rises back to the top because I was recommended the deep root stakes as it encourages root growth downwards where the water tends to remain longer during summer months and because the hard clay soil tends to spread water outwards rather than down like loose or sandy soil. I was told these trees need a lot of water but infrequently so I'm putting about 40 gallon worth per tree every month but I don't know how much is actually reaching the roots. I'll buy the chelated iron asap and dig to see soil mosture content 1-2ft deep.
If it turns out to be over-watering can the trees survive and what can I do other than just wait before the next watering cycle?

Mulch heavily, but leave a ring around the trunk un-mulched. Not much else you can do, imho, but you might rig up some shade cloth to give a little protection from the sun. I have a small Meyer in a pot and had to move it to a location where it got some shade because it was burning.

Do you have a moat under the tree? Do you have sandy soil? If so, I suggest you stop deep watering with hose - and top water it - fill the moat -the moatshould be out to outer tree leaf line and 4 inches deep - and then let water go down... also we use advice from a desert gardening book that we have. I have sandy soil here so water goes down quickly I water (flood the moat) probably twice a week and I fertilize about every 3 wks (prob 1/2 pound of amonium sulphate ) inside the moat..... many would (read desert gardening tree books advice) say that I over water and over fertilize but it works for me. It's 5 year old Lisbon lemon with 6 inch dia trunk and had a bumper crop last year - tree about 15 ft tall. I keep trimming out the top as it's under power lines. If you have clay soil you can't water so often as I do..... you'll have to figure that out. happy to send pic of tree if you are interested

Where, oh where, are you that you have "sandy soil"? Such a novelty in most places around here.

i am in yuma az on the mesa 60ft above the valley. very sandy soil.
to get benefical bacteria in your soil ,you should use
steer manure .
i get mine at yuma nursary it is better quality than lowes or
home depot
go to www.dirtdoctor.com
he has a lot of good info

Jakego- So what happened did you figure it out?
You know clay soil is about the worst along with caliche. It can stunt the feeder roots and the roots will just grow around in a circle, like being in a pot.
If it was over watering which I doubt the trees will survive. Just cut back a little. The yellow leaves will fall off and new ones will grow. Next year try some fertilizer stakes out by the trees drip line. I agree with uman get a moat out beyond the drip line. All my fruit trees have a moats. With clay soil you can also ck to see how long the water in the moat takes to drain down. Might help. Campv

i lost my lemon tree this year and nothing would help. I asked the HD man who seemed to know his stuff and he said it was grubs which were eating the roots. The leaves all came in curled, then yellow, then whole branches were bare. Tried the oil bug killer ..nothing. Tried the grub killer..nothing. Gave up. He said it would probably die, and it did. Healthy for many years. good producer. i think grubs are also eating my grass too. SAD