MBCNSW April 2022 Night Drive – multiple brake problems

Last night was the April 2022 MBCNSW night drive.   Due to the terrible weather we’ve had in Sydney over the last couple of months, it was the first one since January.   The last two were both rained out.   We generally try to go if its raining, but the amount of rain and flooding made it impossible.

The route was one I was looking forward to.   The plan was to do a ‘Bridge to Bridge’ drive – from Windsor Bridge in the north west of Sydney to the Peats Ferry Bridge in the far north.    This route goes through some nice driving roads in the Northern parts of Sydney that are still sparsely populated.  We even cross one of the five active car ferries in the Sydney region.

I had originally planed to get my 250SE out for this drive.   Due to the weather, I hadn’t really used it since February.   Of course, being 2022 Sydney, the weather didn’t’ play nice.   It rained on and off most of the week before the drive, including the day of.    Based on the experiences of the last few months, this really depressed numbers, even though it was supposed to clear in the evening.    From a normal number of 10-20 cars on one of these drives, we had three.

Given it was still quite wet, I decided to take my 560SEL instead.    With a busy work schedule, the weather, and the National Rally, I have not really driven it much this year.   Half way to the start point in Windsor, I started to get a soft brake pedal.   Stopping to check things, my drivers rear wheel was very hot.   The hoses were replaced about a year ago, so I was pretty confident I had a sticky rear caliper.  The 560SEL was to be the backup if something went wrong on the 450SLC just before the rally.   Worked out well the SLC was ready to go!

Instead of proceeding on a drive with twisty roads in somewhat damp conditions, I decided the safest course was to pull out.   However, if I was fast with a car change over, I could re-join the group for the last leg up the old Pacific Highway to the bridge, or worst case at the end point.

After letting the brakes cool for 15 mins or so, I babied the car home, taking a route that wasn’t the fastest, but had the least stopping and starting.   The pedal was pretty good after that, so I think the caliper is probably only a bit sticky.    I have the push the car into the spot it’s currently parked (or I can’t open the doors).  It pushed in freely, again showing the problem probably isn’t too bad.   Still, I’m not going to use the car until this is fixed.

I decided to get the 250SE out after all.  The weather really had fined up at that point and I was keen to get behind the wheel of that car again.   I refueled and got almost to the point where the other two guys would be coming up from the Berowra ferry to the Pacific Highway.   I was about 5 minutes ahead of them, so the timing had worked out well.   Then, it happened again.   Soft brake pedal on the 250SE.   As it happened the last leg of the drive was a loop, so the ending point was about 2km from where I was.   I pulled in there, and again checked the wheels.   Sure enough, both rear caps were hot, but the drivers side was quite hot.   Fronts were fine.

It was pretty clear I had a similar problem causing my soft brake pedal on the 250SE.   In this case, the hoses are not brand new, so could be related to those as well.    I let the brakes cool while I waited for the other guys.  We were stopped at a 7-11, so bought an ice-cream to pass the time.  The car had been running reasonably well.  Unfortunately, I was still experiencing that occasional misfire that I’ve been grappling with for the last 12-18 months.   I’ve been through a few tanks of fuel, so it can’t be that.  Plugs, points, cap, rotor, condenser, coil and injectors are all new.    It happens at all temperatures, at idle and under load.   Changing those things has made it much better, but not fixed it.

After a while, the other two guys arrived, in a 500SL and a 420SEL.   While the 500SL was never sold here in Australia, I think its by far the pick of the bunch and I would prefer it over our local 560SL.  They had a good drive, and the weather had been good enough for the R107 to drive with the top down the entire time.   Luckily neither of then had a soft brake pedal.