Well after adding the (liquid) BarsLeaks and installing the 7psi cap and an uneventfull test drive to Krispy Kreme the morning after there was a nice large puddle o' coolant under the motor. Weep hole had coolant coming out of it so out came the waterpump. Replaced with a japanese pump that has a stamped steel impeller. I would like to have been choosey but I need the car and the price was right. The whole replacement was easy as waterpumps go except for those little 10mm bolts that hold the fan/clutch on. What son-of-an-unmarried-woman designed that setup? Just a little more room and you'd be able to use the box end of the wrench but no, you get to use the open end and round the little buggers off! Nothing a mini-sledge and cold chisel couldn't fix. Anyhoo, the new pump is in, no leaks so far. Still using the 7psi cap as I see no reason not to. Poured the old coolant back in so the BarsLeaks is still in there. Regarding running pressurized or not. I ran 260 miles with the cap loose and had no problems. Then I made one short 15minute trip and it blew some coolant out the tank. Wierd. The MB/617 uses a standard-size cap so you can get them at any parts store and in many different pressures. 7psi seems very reasonable considering that MB's new superceded cap is a 1.4bar and that is 20psi!!! 7psi is about 0.4bar. SPO, sorry I missed the gtg. See ya at the next one! Thanks for all the input guys! It helps to know someone else is thinking this stuff through with ya! RT

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