Starter motor on last legs?

My starter has started to give me problems, some days it won't start, does'nt even turn over and starter does'nt engage, this has begun to get anoyingly more frequant, so last night at work I decided to take the starter off and have a look at it, (what a mamoth job!) I could'nt get the starter out without taking all of the exaust manifold and down pipe off, so i just cleaned the spigot shaft and drive gear and then lubed it with spray on coppa-slip, when I put it back together I tried it and nothing! so I tapped the solenoid and it started after switching it off and repeating the process a couple of times it seems to have sorted the problem. I am thinking that the soleniod is the problem and not the starter, can you buy the soleniod on it's own? it's a bosch starter and does'nt look very old. I may have caused the problem after a couple off pay-n-play days wading? anyone else had starter probs???
I have heard a couple of horror stories about them not lasting long, one guy saying that he's had 4 sarters in as many years!

Just took the starter motor off again, after removing the exhaust manifold and down pipe, I got it on the bench and stripped it down and was amazed at how much dirt and crap was in there, no wonder it would'nt start! I have cleaned it all out and the solenoid as well, then greased it up and built it back together using silicon in all of the joints, so hopefully it should keep all the ****e out now. The landy now starts first flick of the key happy days.

Ha! Good work! I love the self-answering fred!!!

Starters on landys are notorious for sticking. There's a gear inside commonly referred to by mechanics as a 'dog gear.' Occasionally a little tap with a lump hammer can rectify this sticking so that the starter engages on ignition. I had mine recon'ed for 40 quid - looks like your bench work has saved you that cabbage which you can now spend on another problem!