N_Halbert

My 90 S2 is having the belts and seals replaced. My mechanic found the rear half of the timing cover was broken and sourced a replacement. There is one curious difference between them. On the bottom under the crank there is rectangular tube molded into the housing. On the replacement it opens into the timing belt. On the original this opening is closed and was molded that way. I had always puzzled about this when under the car.

I am wondering if this is an older part and later they determined this access point was unnecessary or if mine was never fully processed?

Is the opening to be left uncovered or is there a piece that should cover it? There appears to be molding features for adding captured nut clips.

harrisonrick

Could be a cover from a 944S...there was a rubber tube from it to the airbox on my car...Porsche eliminated that. No worries, just block it off.

PorscheDoc

There are numerous variations of the timing belt covers. Some have the port on top, some don't. Some have the lower rectangular square opening, some do not.