My current sprkinler heads are sitting too high (1/4") so I want to re-seat them (4) lower. They have been like this for about 1 yr now. How do I cut the lawn around the sprinkler and lower it some?
I may also need to install a few sprinklers. How do I cut through my lawn to do work and then put the pieces back w/out making a mess or leaving huge gaps etc?...
Thanks in advance.

Cut the sod using a shovel, a straight hoe, or lawn edger. (Mine is about 12" long with a serrated edge Quite a lawn weapon) Carefully remove the sod and stack it aside. Do the repairs or construction necessary refill the hole and carefully lay the sod back in place.

For new construction there are machines that carefully lift the sod and plow in the pipe.

You can cut a little ring of sod up around the sprinkler and set it to the side to be put back once finished. I don't know what kind of grass you have, so it may or may not repair itself.

Put all the dirt you remove on something so you won't lose any and can put it all back in the hole. You still may have settling. Don't worry. Fix it later.

Heres a question or 2 or 3, though.

1/4" isn't a lot. Did you install the system yourself? Was a hard, threaded sprinkler riser used to connect the heads to the lines? Or was a flexible riser used? (swing pipe, funny hose, etc.)

If the flexible risers were used, you may be able to push them deeper with no digging.

I just don't like the sprinklers heads being so visible.

I did install this myself and it's all hard threaded sprinklers risers.

My second dilema is to dig through the lawn so I can put sprinklers accross from one another (should have done this before) to get even coverage. It's a rectangluar design about 20' x 8'. Can I do this myself or have a lawn service perform this?
It sounds like I can just use a shovel and cut through the lawn so I can perform all this work. Is it this simple?

Thanks again.

You want to make sure the lines are deep enough to be protected from any surprise freezing or other damage.

Not sure how far you are trenching. If you only have a short way to go, a shovel and mattock will do the job. Just takes more time and sweat than a trencher or pipe puller.

There is an installation method where you bring the 'riser' up at a shallow angle using flexible pipe. Then you can adjust the level very easily as grasshole mentioned. The reason for that method is to keep from breaking the hard pipe by hitting it with the mower or kicking it.

To install the new line, look into renting a Ditch Witch motorized trenching tool.

OK here is a pro's advice. You a sharp shooter shovel and excavate the soil about a 6 inch radius, and deep enough to fully expose the horizontal feed pipe, riser, and sprinkler.

Discard the soil, unscrew the head from the riser, and use a shorter length rise so that the top of the sprinkler head is flush to slightly above grade.

Back fill hole with 1/8 inch pea or crushed granite road gravel. It will make repairs real easy down the road, and does not settle much and will take a lot of weight.