With winter well & truly setting in here in the Northern Hemisphere and sunny days becoming few & far between, here are some winter storage tips to consider for your R172 Roadster:
> Before parking your R172 up for the winter, take your SLK/SLC for a good 30 minutes plus run out on a dry day before parking it up. This final drive will help reduce the condensation in the Engine that a cold start produces, but this run out also reduces the amount of moisture in the body panels.
Also make sure the brake pads are dry, especially if you washed the car just before putting it away or parking it up:
> Also run the Air Con for ~15 minutes during the first part of the 30 minutes of a run out, then turn the Air-con off during the second half of this final run, to dry the ventilation system out. The lubricants in the refrigerant keep the seals gas-tight, which is the reason for using the Air-Con on a regular bases, regardless of the roof being up or down!
This is especially important for newer R172’s that have “R1234yf” Refrigerant that is slightly more environmentally friendly, but on the down side more prone to leaking….. (Older R172’s have the original cheaper, less flammable “R123” Refrigerant)
> If safe to do so & the wheels are chocked, leave the hand brake off – Not so easy on the SLC, which is applied automatically as soon as the drivers door is opened…
> Pump the tyres up to ~38 to 40psi to help stop the tyres getting a flat spot – As the cold weather sets in they may well be well below the recommended pressure anyway… (Just remember to adjust the pressure to the correct value, when going for the first run out in the spring..!!) Additionally if the Handbrake if off, you have a manual R172 and space permitting, rolling the car back ever so often, then forth every so often will help with the weight of the car sitting on a different part of the tyre.
> Though the petrol SLK/SLC fuel tank is sealed, better to leave it fairly full of decent quality 98+ Octane fuel during any period of non-use, to help reduce condensation in the tank and also leaving the walls of your fuel tank exposed during storage can invite corrosion in the presence of moisture, especially if the fuel contains Ethanol. Here in the UK, all petrol fuel now has to have at least 5% Ethanol, but at least the pumps now have to be labelled – So don’t fill with “E10”, un-less you have no choice. The Ethanol content of the petrol does not store well for long periods in a cars fuel tank, so fuel stabiliser could be considered if the car if likely to sit for periods in excess of 3 to 6 months?
> Consider changing the Engine oil, before laying the car up for winter, not after being laid up. Better to have fresh oil, than heavily contaminated oil sitting in the engine over the winter..
> Allowing a car battery to go flat can damage the battery & will shorten it’s life. If the battery is well charged, the battery will last 4 to 6 weeks, but after this & especially if the battery was not fully charged before being laid up, starting your R172 could be a problem. On any modern car including the R172, trying to start the car with a near flat battery will throw error codes and course electrical gremlins..
Running a car while stationary to purely charge the battery is not good for the engine. So if mains power is available, connect the car to a Battery Trickle Charger like the “CTEK MXS 5.0” model that is used by many SLK/SLC owners – Accessing the battery under it’s cover is not so easy, so using the “Jump Starter Point” can be a better option:
> A Car Cover is another option especially if the car is parked under trees, but only fit them on a clean car as the grit under the car cover could scratch the car – Also make sure the cover is a good fit, to minimize rubbing of the paint work..!!
> If a car cover is not used, a Fabric Wheel covers or a shaped piece of ply board might be another option for outside storage, to stop the rain making the brake disks rusty..??
> For R172’s lucky enough to be stored in a UK garage with mains power, whether in regular use or stored for the winter, my final recommendation is a “Desiccant Dehumidifier” to help control how damp the car gets in the garage. The “Desiccant” part is important, as it allows the Dehumidifier to continue working down to ~3’c. Reducing the Humidity helps to stop the brake disks going rusty and also reduces corrosion on the electrical connectors. A model that I’ve used successfully for a number of years is the “EcoAir DD122FW MK5 CLASSIC Desiccant Dehumidifier” and can be found on-line for around £158 (November 2020)
So those are My winter storage tips, feel free to comment below, or add your own tips.