Oil Pressure

[drrhein]

http://www.dotphoto.com/go.asp?l=drr...4362631&Pres=Y

My 1985 500SL euro has recently developed an oil pressure problem when hot. The pressure reads zero at idle. However if you look at the oil spraying on the camshaft (looking through oil filler hole) there is no difference between when cold and reading 3 bar and reading zero. Another thread suggested I look at the pressure sender, but I can't find it anywhere. The pressure relief valve, suggested by another, is on the oil pump and the pan has to come off for access. (engine has to be removed to get pan off) Anybody had this problem????

Dennis

[deanyel]

And how does the gauge behave at other than idle?

[drrhein]

above about 800 rpm everything is normal 3 bar.

[deanyel]

Your readings are not that far off - it's often well under 1 at idle. Your owner's manual should say what to expect. In any case I would start with a new sending unit, not that expensive or hard to install. It's located at the base of the oil filter housing, accessed from below.

[blackmercedes]

My old 190E did the same thing. Idle pressure would be zero, and then it was fine right off idle. Replaced the sending unit, and it was fixed.

[drrhein]

Replaced oil sender, Problem fixed!!
Thanks to all that offered help. Especially the sender location, there it was, right next to oil filter.