As nhdoc mentioned, its the guides that'll get you and I think you're on borrowed time. Its heat and age that do it.

If you can't do it real (real) soon, at least listen for unusual/louder engine noise at first start. If it makes a metallic slapping noise at start up, I wouldn't run it for a minute.

Shut mine off because of this noise - had it towed and, sure enough, broken upper rail (at 97K miles). Probably would have lost it had i driven the 4 miles...

Kevin

__________________
"Dangerous with a wrench...and not smart enough to know it"

Stable (in order of acqusition):
'84 500SL, 280SEL (Euros)
'77 280SE. '90 560SEL
'79 450SEL 6.9,
'95 C280 (totalled by daughter 8/07)
'81 280SL (rescued) '88 300CE
'86 560SEC '95 C36
'01 CL55

DD's: '04 S500 4Matic (SWMBO)
'04 F150 Crew