1991 BMW 735i Q&A
1991 BMW 735i Question: temp/cooling sys. please read need help!
this car was well taken care of and i drove to work the other day and smoked a cig.w/ac on, as always, and bofore i was done it was dinging saying coolant temp. so i shut off car and waited 2hrs. Then tried to add water but was full. So drove to the store and back and the upper hose on radiator was still squeezable after warmed up .... should it be or is the thermostat sticking. today it went above half but back below half once i started moving and never did before. owned car for 10 months thanks - bemin735i
Have your radiator cap, viscous and thermo electric fan and water pump checked. - Chow
There is a burping valve on the thermostat( a 8mill bolt that sticks out of the top of themostat). When topping off always open the burping valve untill h2o or coolent flows out. Tighten up bolt, but keep resivor cap off and start car. Once 735I is at running temp open burp valve if only fluid runs out, without presureized air spray. Close it up and top off resivor and tighten up lid. If there is still air in system keep filling and burping untill air is gone. Don't fill resivor to top while motor is cold. This can potentailly split resivor if overflow is cloogged or nonopp. Good luck - Visitor