Ah, got it.

Once of the issues with AC in the 190, is that the aux fan will not flow enough air to keep pressures down, and fan on the motor hardy flows any air at all unless the electric clutch engages it when it reaches the temp to do so.

__________________
1984 500SE
1985 190E 2.3-16
1997 Jeep Wrangler
1998 Dodge Durango SLT 5.9
1951 170S
1996 Ford F350 7.3 ZF5 swap