I recently purchased a 1994 855. It has very loud lifter noise for the first 10 minutes then quiets down. I went to the dealer for suggestions and was told it was common for the oil pick up tube o-ring to let air in and produce the ticking i'm experiencing. Has anyone else had experiences with this? How difficult would it be to repair on my own. I'm afraid that I'll have to do something soon as it is beginning to do it on and off when warm now. I just can't afford the 6 hours to install a new o-ring. Thanks for any advice.