W215 Drain hole location under bonnet- where?

[Sycamore]

I have only had my CL for a month, and have been thinking on and off about checking this fabled drain hole for blockages as I don't fancy £££ worth of ECU destruction and a wet footwell thrown in.

I have searched on here but haven't found the info, so I thought I'd ask about where this drainage hole is. Several hours of rain the other day made me think that it is time to get this particular task done!

Any answers welcome.

Rohan

 

[John Laidlaw]

Does this help?
https://mbworld.org/forums/cl-class-w215/666025-cleaning-leaves-dirt-under-hood.html

 

[Craiglxviii]

Do you mean the heater air box?

There are any number of locations under the hood of a 215 where leaves get trapped. Get a carrier bag, strap on some latex or silicone gloves and poke your hand into:

The recess underneath the windscreen, RHS. Behind the A/C refrigerant tank, there’s a curtain of rubbery material with a fringed/ fingered edge. Get in there and pull out handfuls of leaves (I found s dpare headlamp washer jet in there too). Get a damp rag and clean it all out then spray Dinitrol wax all around after drying.

Same LHS behind SAM.

Then go and hunt out all the books and crannies. I use a long pair of modelling tweezers and a vacuum cleaner with a v narrow snout thingy.

 

[brianbrian]

The heater box drain is the main one for problems, also one each side, end of front wings near bulk head.

 

[peterws1957]

Don't know if it's the same but on the 216 the worst culprit is the drain behind the passenger side bonnet hinge.It bends at 45 degrees near the opening - a really bad design. Always gets clogged.

 

[Sycamore]

Some really good info here, thanks to one and all.

 

[Sycamore]

First (easy) job completed- and not too soon it seems.

This drain hole was not completely blocked but it was quite full of tree debris.
Drainage can hardly have been optimal.

All sorted out now.

 

[Naraic]

Well done.

 

[peterws1957]

First (easy) job completed- and not too soon it seems.

This drain hole was not completely blocked but it was quite full of tree debris.
Drainage can hardly have been optimal.

All sorted out now.
View attachment 44897

Well worth regularly checking the drains under the bonnet. Get blocked and watch the passenger footwell fill with water and the electronics throw a very expensive wobbler.