The Effects of Cold Temperatures

Greetings!  Welcome back to the blog for some more bimmer and auto enthusiast goodness!  It’s been another busy week, so let’s take a look at a few of the latest happenings in the shop.  The weather lately has been cold, bitterly cold.  And, unfortunately, the cold can do a number on cars, as we’ll see in a minute.
We were excited to have this nice 1985 BMW 535i come in to the shop.  It’s an e28 Euro spec bimmer, made for the European market, which has different crash standards than we do here in the US.  Don’t you just love those Euro bumpers?  We certainly do! This poor car just wouldn’t start.  Upon inspection, Reggie found it had a loose battery cable, which meant no juice was getting to the engine computer.  This car is just plain cool.

We also had a 2001 BMW 330xi in for quite a bit of work and some routine maintenance.  Let’s dive right in!   The owner had noticed oil coming out of the exhaust when starting the car on a rather frigid day.  The system over-pressurized, due to frozen condensation in the PCV valve.  This caused oil to blow into the cylinders and out of the valve cover gasket.  Unfortunately, this is a common problem.  Needless to say, the PCV valve, hoses and valve cover gasket will be replaced.

Reggie also found that the intake hose was quite torn.  Add it to the list to replace!

Removing the PCV valve (oil separator valve) was not an easy task.  It’s buried down deep in the engine bay, and it’s a part which is both horizontal and vertical in shape.  There are two ways to remove it: (1) Remove the intake manifold; or (2) Uncover the intake manifold…which is what Reggie was hoping would do the trick.  And…thankfully, it did!

It’s hard to see the PCV valve to get a good photo of it, let alone trying to remove it!

And here is the new PCV valve.  This part now comes covered in insulation, which makes it a bit larger in size than the original!   The good part about the insulation is that it keeps it from freezing in colder temperatures.

Oil had seeped out around the valve cover gasket:

New parts and new tires for this bimmer!

Removing one of the hoses that will be replaced:

Oil and condensation had frozen and expanded in this section of the breather hose:

The original PCV valve…also filled with the same crud as above:

Reggie removed the dip stick tube to clean it and replace the o-ring, thus ending the dis-assembly process.  Below, Reggie is seen reinstalling the dip stick tube.

All of the hoses need to maintain a certain level of pressure in order to release pressure from the bottom end of the engine, while doing so efficiently and in an environmentally sound manner. When the freezing occurred, the pressure had nowhere to go and took the path of least resistance to escape.

Reggie removed the valve cover gasket, which had become quite brittle!

Cleaning the valve cover:

The new valve cover gasket awaits installation:

The spark plugs were also in need of replacement:

The oil had gotten to them too!

New spark plugs: check!

Draining the coolant and refilling with BMW coolant:

All four tires will be replaced:

This sensor was carefully removed and set aside for a moment…

…while Reggie saw how best to remove the fan and fan shroud to make room to replace the water pump, thermostat, and expansion tank:

These parts were replaced as preventative maintenance, so they won’t fail out of the blue, as they are known to do.  More on this in a moment.

Reggie used the thermostat bolts to remove the water pump.  As the bolts were driven against the engine, the water pump was pushed outward for easy removal.

This water pump was not pretty.  You can see where coolant had seeped out of the weep hole.

The old water pump (right) had a composite impeller versus the metal impeller of the new water pump.  Metal impellers are preferred.

Old and new expansion tanks, which hold extra coolant in the pressurized coolant system:

Reggie tightens the bolts on the thermostat and snaps the upper radiator hose into place before installing a new serpentine belt:

That wraps up this week’s edition of the blog.  We’ll be back next time with updates on the S50 project and some other cool stuff.  Have a great weekend!