Tension problems!- tune up? Any self tune-up advice?

I am having to tighten my tension to get a nice stitch, much tighter than recommended.  I'm worried if I sew like this too long I will cause more problems.  I've called a couple sew-vac shop places to get ideas, but we are very rural and I'm finding nobody seems qualified to answer my question.  They all just recommend a tune-up.  I'm fine with that, and will give it a try, but is there anything I can try on my own first?

Has anyone had good luck tuning up sewing machines themselves?  I wouldn't know the first thing about opening up a sewing machine, so be honest, do I just need to take it in somewhere or are there some fairly simple things I can do first?

It can't hurt to do a basic cleaning and oiling of any parts you can reach.  Your manual should give you some instructions, but if not, here's a site which goes over some basic cleaning:
http://craftnectar.com/2009/03/09/spring-cleaning-for-your-sewing-machine/
and oiling:
http://craftnectar.com/2009/03/12/oiling-your-sewing-machine/.

It's amazing how much this can help.  A friend of mine is a crazy seamstress who sews hours a day.  She has had her sewing machine for over 5 years and has never taken it in for a "tune-up".  She cleans and oils it herself, but other than that she doesn't do anything else. 
With my machine, I had it for less than a year and had to take it in for a $100 tune-up because nothing I did to it would alleviate the tension issue.  The tune-up fixed the tension issue. 
I would start with general cleaning and oiling, replacing needles and re-threading, and checking for burrs (needle nicks) on the bobbin hook and shuttle.  If everything looks good and there's still problems, I suggest taking it in. 

Irene...thank you so much for posting these links. it is so helpful to know all of this stuff.

Thanks for the links!  I am going to try working on it this weekend.  I hope it works!  I'd rather not have to spend the $100... imagine, not wanting to spend money right now.

I, too, am having tension problems. So glad to have found your post. I did have the maching cleaned at the Singer store and was told it was sewing fine -- including the tension, which I asked about. The machine is over 25 years old, but it seems that I've never been completely convinced that the stitches looked correct.

Maybe it's time to start shopping. I don't sew that much and it's mostly just for crafts, etc. Guess I'll check out the other forum with recommendations on machines.

Thanks, GT

My bobbin thread keeps breaking. Any ideas what to look for that I can fix myself?

This video (for me) was the BEST in explaining tension and helping trouble shoot! 

http://my.allpeoplequilt.com/bettertv/?cid=507869917&lid=715980676&tid=1733163088

If you are good with drawings and explanations, then try this: 
http://www.sewusa.com/Sewing_Machine_Repair/Thread_Tension_Settings.htm

*HUGS*
Jackie Sue
(would love to win #4 in the 3/27/09 giveaway!)

For the bobbin thread issue, have you checked that your needle is in the machine in the correct position, do you need a new needle-  it could be a defective needle, or the wrong type for the machine.  (is the smooth side facing the right way?  is it pushed in far enough?)  If that's okay, can you remove the metal plate over the feed dogs and check for lint build up.  (last time I had that issue with my featherweight, that was the case.)  The final things to check for are tension in the bobbin case (you can do a search on how to adjust this) or a burr someplace on the lower part of the machine that is catching the bobbin thread and breaking it.

Try this page:
Resources for DIY Sewing Machine Repair & Maintenance

This is all such great information!  Everyone has been so helpful!  Also, you must have seen the spring cleaning segment on the blog, yes?  Also helpful for basic tune-up info.