Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Trad Air Condtioning

Richard,
The drains are there, at the rear against the bulkhead. Here are some pics of my 68 reg +4. I had the same trouble as you, water getting into the car in heavy rain. I found a tide mark in the heater air box and the drains that are above the bottom of the box. I lined the bottom with closed cell foam to raise the floor level.
Cheers
John

Many thanks John07. Your pic suggests there are a further pair of spigots/drains? on right hand side of box.

TBH it's only on rare occasions I've suffered from spits of water coming through vents but your post invites further investigation.

Yes that's correct, on my car there are drains on both sides.

Richard, thought this underside image might be worth tossing in. From a pranged 2016 Roadster.

Thanks John. Just come from checking in the garage. There are in fact six drain/vents. One each side at the front half way up as drains seemingly for the rotary fan housing and two lower at back and each side. The lowest of these seems an adequate drain for the air inlet chamber so will leave as is.

I then checked with my head in each footwell. No further drains seen although I can feel significant holes in the back of warm air outlet box which makes a farce of shutting the air vents A powerful lamp shining through front vents allowed me to see the heat control flap was shutting fully though.

ETA: just seen your very helpful picture Rog. May check again but those drain tubes appear to be hidden on the 3.7 Roadster given the width of transmission tunnel. Might be visible from underneath with a torch. Will check later.

Yes there are drain spigots on both sides of mine too but you will see that the form of the airbox is different on mine to accommodate the aircon evaporator. The principal of blocking hot engine bay air (and potential fumes) remains the same for aircon and non aircon systems.


Foam cut to shape to fit the top of the airbox.


I made the blocking piece from a sheet of PVC cut and bent into shape. Where the material was bent a crack opened but it is only in the upper surface and I will use a little black silicon to fill it. If ever I replace it I will probably use a piece of aluminium instead now that I have the shape needed.


Blocking piece in place.


How it looks after a few years of use. Note the impression left by the edge of the louvres. It only just covers the edge. Probably the louvres should have been placed a centimetre closer to the hinge.


Tube fitted to lower left-hand drain spigot. I only worried about the left-hand side because condensed water from the aircon evaporator was getting under the ECU cover and dripping into the footwell past the main cable grommet (the one where all the cables pass through to the back of the dash). The dried leaf is an optional extra


Showing the neoprene gasket that I place under ECU cover flanges. The idea is to stop possible ingress of water that could then drip into the footwell. After taking the photo I noticed that the cable grommet was a little out of place. I have fixed it


This shows the drain tubes at the bottom of the in-cabin part of the air system. If they do not exist it would be possible to fit them but it would not be easy with the gearbox cover in place. Even in cars without aircon I believe these drains would be desirable due to the possible ingress of rain water.
.

This last photo shows an example of poor design that creates long runs of tube but, worst of all, the tube from the compressor to the evaporator has a section which runs behind the hot radiator. This could be resolved by swapping the position of the compressor and the alternator.. The tubes which run to the condenser (aircon radiator) that is positioned in front of the radiator are also excessively long and whilst this is not a problem for the system it is untidy and unnecessary. It is indicative of a "near enough is good enough" attitude to fitting the aircon system.

Thanks Rog. Your photo makes it very clear. You posted yours while I was preparing my post

Just checked again and whilst I cannot see pipes due width of transmission tunnel, I can feel them and definitely not trapped. Quite large diameter around 10mm id, both running forward through bulkhead. Pic of passenger side end of drain pipe resting on clutch slave plumbing above bell housing.



Given the diameter I'm surprised it doesn't let water in never mind drain!

Richard, if you take out the plastic foam filter I think you can peer down into the heater fan / airbox and see the drain holes at the low points

From a dull memory in years past the sponge like material was perhaps thought to hold dampness and eventually cause corrosion.. ?