How and why overhaul a suspension fork. Technical general info needed :D
 

First off the fork im looking into rebuilding is a Spinner Edge 4. Its a bike that at this point I don't want to put much money into. The fork feels unresponsive, it suspends then doesn't seem to bounce back as fast as some forks I use. I am a very competent mechanic, but typically deal with road and rigid MTN bikes.
So could someone explain to what purpose you overhaul forks. Hubs are obvious why overhauling/rebuilding is necessary, but I cant see why forks need to be overhauled, something about seals and things. Or if that's just the way some forks feel? I understand some use oil and some are air. So what I like to call "technical general" info or "low down" on forks and function internally would be excellent. I know some forks are just disposable but the one I have is hardly used. Any info is greatly appreciated. Please no "get a new fork" or "take it to a shop" suggestions since I have plenty of suspension forks laying around but want to get into this, Im long over due. Thanks all!

Your fork probably falls into the disposable category you mentioned.
If anything went wrong with your fork I doubt that you'd be able to find replacement parts for it.

You ask what's the purpose of overhauling a fork ?

The fork has moving parts that can wear out like seals and bushes.
Worn seals can let contaminants into the fork and won't hold air in a air fork, worn bushes will give unwanted side movement in the fork - the fork should go up and down not side to side.
Forks also have lubrication in them such as oil or grease.
Dirty oil, low oil levels, dirty or dried up grease means the fork won't work as it should and move smoothly.

Oil and air shock have seals to keep the air pressure or oil in the shock. Seals are what keeps the lowers from rubbing on the stanchions or uppers. Forks are overhauled when the seals leak or don't hold air from age or wear. Also to switch out the contaminated oil or oil weight change to change the way the fork performs. Some Rock shocks need to be service every 80 hrs, oil shock. Look online the the tech docks for you forks and then service as needed.

The purpose of a fork overhaul is to return the fork to an as new status, as cobba notes, this fork probably is disposable, as the overhaul can only be done on forks with easily avaliable spares, which is limited to manufactures like Rock Shox, Fox, Marzocchi, Magura, White & Manitou, most others are only bin-able when they have been well used.

If you can swap it out for another, do this, or you are just going to get the suggestions you don't want

Thanks all! I have come to the same consensus basically. I will just ride the fork for a few rides and see how intolerable the performance is and upgrade from there. It looks like the overhaul how to-s are for forks in the $200 range give or take and serious about the ride. Me not so much. :D

Put some oil on the stanchions and compress the fork a bit to get some lube on the seals, it might make it rebound a bit better.

Some bottom-of-the-barrel forks only have a cheap spring or elastomer - and even that only on one side! The piston look is for show. These wear out after a while, especially if it sees regular rough use, and then the fork is junk.

no Google Fu to get you tech bulletins?