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

Well done Richard!

I have more information for you.
1. I have found the why of this system
2. I have a generic diagram of how it supposed to work that will make things simpler. It will also please Luddite as it does me.

1. Some years ago, the USA's EPA got involved in gases released to the environment. Though the specific sad targets of "degassing" was not automobiles per se the manufacturers were forced to radically change their automobiling cooling systems. The investigators concluded that automobiles, when venting the coolant system, also released undesirable gases. They wanted none of that. (I do not know as yet whether this is reflected in any other automobile legislation elsewhere.) This is curious because a degassing system will vent every time you fill it with coolant. There also special coolants required. Can you check in your Roadster what coolant the MMC requires? The degassing systems, however, hope to remove gases from the very rare automobile cooling venting.

(I do not know as yet whether this is reflected in automobile legislation in other nations or to what extent.)

The oil cooler, on most cars, is a separate, smaller radiator to the engine's main radiator, which maintains an oil supply at a consistent, optimal temperature. Its purpose is to cool the oil passing through the coils, thus improving the engine and the transmission's lifetime. They are normally situated in front of an engine's cooling system. Sadly, that creates the Ford engines most frequent defect, though I have never hear of this one from the Roadster group. That being said I do NOT normally mechanically track Roadsters, though I like the 3.0s very much. https://tuningpro.co/ford-3-7-cyclone-engine-problems/

Gets more interesting. There are alleged engine benefits, (throttle response, cleaner engine, better mileage, more virile libidos, in eliminating the cooling system's downsides (that is pushing exhaust fumes back into the engine). It migt explain the varying bhp one sees in these engines from regulatory regime to regime. Any Roadster person hear of a "delete kit".

Cars are sure changing!

gmg

I believe the Mustang S550 (sixth generation) built 2014 on had an oil cooler. Earlier versions including the 3.7 V6 2011-14 Cyclone engine which the 3.7 Roadster used have neither oil cooler for engine or transmission. No EGR either thankfully.

I think this applies to all trads ex factory excepting the 3 litre Roadsters undocumented oil filter heater/cooler which can't have made much difference.

I suspect this won't be the case with current CX series though. Certainly our 2016 F54 Mini with B47 diesel is part of a massive recall to replace EGR cooler due to faulty batch. Current situation is they are building up stocks to service the recall.

gmg, thanks for posting the cooling diagram, it is one of the best I have seen, however in truth I have little interest in the complexities involved in trying to make the simple combustion process that might be required to keep an ICE engine compliant with ever evolving regulations and in the process of doing so excluding all but the very determined owners from repairing and maintaining their own vehicles...?

Takes me back to a time when California led the world in strangling the I.C.E requiring ever more cc to match previous models power outputs... early seventies or thereabouts..?

Were I a younger man I suspect I might have tooled-up to tackle maintenance of more modern machinery. I kinda gave up around the time Mrs L bought her (BMW) Mini Cooper many years back and let the dealership take over looking after her subsequent cars. I had more than enough of technological advance while trying to earn a coin at work, to get further involved as a hobby, was just not on my radar..

On the other hand I do still try to keep up to some degree relative to understanding aspects of my 991`s foibles, repair and maintenance, so hopefully I may not be completely ignorant of modern ICE cooling systems..

I note as yet no one has come back as to the designed operation of an "open" pressure release cap as might be fitted to a recovery system.... But then if none such was ever fitted to a Morgan.....?

Thank you once again Richard.I think we can begin to come to some preliminary conclusions on the AC and cooling..


1. AIRCON If it were me, there is no question that I would put in a shutoff/bypass valve to sort the AC anomaly, unless someone can figure out this would cause a MOT-detectable increase in emissions.
The routings posted indicate that is unlikely. (famous last words)

2. T'were me, I would remove the EGR valve with a blanking plugs the US market sells for that purpose for these engines. Degassing laws primarily targeted other industries where it was, admittedly needed. Degassing automobile cooling system venting is a tad extreme. Blanket legislation can often upset reason. No one's fault, laws are hard to draft. Technology has taken us far beyond the simplicity of the Ten Commandments

3. If I had an earlier Morgan Roadster with the system, I would increase the size of the degas bottle to the later size, preferably in metal.

4. T'were me, I would quickly buy a proper radiator made for Roadsters. They will extend below the short radiators the MMC use, but after a preliminary discomfort when I began using them, I realized their extra length cannot be seen and/or be hidden at the owners open. But we should discuss rads.

You have got me deep into Roadsters! That is a first The CX series is many steps too far! Beyond saying that I like the spec of the Plus Four the CXs are too much for me. It always takes many years (decades) to sort a design with MMC production numbers.

Lorne

P.S. Discussions like this make me feel I am fortunate, enough so to feel guilty on occasion. The 2002/2003 MMC/me recreation of my destroyed 1984 was blessed by the Cdn Federal/Provincial governments as a 1984. So it was officially a reg-free classic the day it arrived at Montreal harbor 21 years ago tomorrow. Ergo, it was not subject to any rules save thosenes I set for myself. That being said, I learned to respect the trad template and make it my arena. No game is fun without boundaries.

I have thought quite a bit about whether or not to make a contribution to this topic.

The very first thing I would say is that I completely disagree with Lorne as to the reason why hot air continues to circulate when the heater knob is turned completely anti-clockwise.

The heater knob can be very stiff to turn and this does not help. One of the first maintenance tasks to perform is to remove the dash and make sure that the heater knob quadrant is clean of dried grease and dirt amd adjust it so that it is free to turn. The quadrant acts on a semi-rigid wire cable (a bit like the old choke cables) and operates a flap in the heater box which controls the passage of air. It is important that the cable outer is adjusted so that the flap can be fully closed. When fully closed no air should be passing over the heater radiator and all the air entering the cabin should be cool (?) outside air. The flap proportionally controls the path of hot or cool air. The heater radiator and the aircon radiator (technically called the evaporator) are not in the same internal compartment of the airbox. 

In reality there is a design error which allows hot engine bay air to enter the airbox. The foam rubber sealing strip which surrounds the top of the airbox and seals the airbox to the underside of the bonnets is left open for an inch or so on either side of the hinge. This leaves a large opening for the ingress of hot engine bay air. My solution may be seen at here and here

Regarding a cut-off valve for the heater I do have some disagreement on this. The idea per se is not bad however if you have airconditioning you may want to have a combination of hot air and air dehumidified by the action of the airconditioner. This is nice to have on a wet cold day when you get into the car with damp clothing and the whole of the inside of the car starts to fog up.

In order to have both a cutoff valve and heat when required a system could be set up with an electric solenoid valve and a microswitch setup to function together with the heater knob quadrant. This is probably not really necessary if the heater control flap is closing correctly.

OK. Now I will move on to the airconditioning system. To my mind, at least with the Plus 4, there are several design issues, some of which are easilly addressed and others not.

Firstly the aircon compressor is fitted to the wrong side of the engine. In order to reduce the run of the pipes the alternator should have been swapped to the right hand side of the engine (kits are available) and the aircon compressor fitted to the left hand side. This would shorten the run of the tubes but above all whould have removed the need to run a tube through the hot air zone behind the radiator. On my car some of the tubes running to the separate aircon radiater, mounted forward of the engine radiator, are excessivly long. Also the factory fitted very little insulation to the tubes, something which I have rectified where possible.

Now, inside the cabin, the design of the Morgan almost dictates that the air outlets are in the footwells. I have considered several solutions to pipe air to, or just under, the dash but I have not really found a solution.

Regarding condensate from the aircon entering the cabin there are two issues. There are drain tubes from the bottom of the in-cabin part of the airbox. If these are squeezed (or blocked) at some point condensed water will accumulate in the bottom of the box and leak or spray out into the footwells. Note that this can only happen when the aircon is running: the heater radiator can not condense water out of the air, the laws of physics will not allow it. If you are getting water entering the footwells when you do not have aircon running you must look for another source.

The second point of ingress of water is from above. There are two spiggots from the right hand side of the airbox, in the engine bay and above the righthand footwell. These may be partly hidden by the aluminium cover over the ECU. The lower one, in particular, drains condensate, and perhaps any other water that enters the airbox, but it is not fitted with a drain tube. Water and condensate can flow across the top of the footwell and throgh cable grommets.  My solution was to cut a 45° piece off the end of the spiggot and fit a drain tube. (I will try to post a photo tomorrow) The other thing that I did was to fit a thin self-adhesive neoprene gasket to the flanges of the ECU cover.

I hope this helps to clarify how the ventilation box, with or without air conditioning, functions.

Thanks for heads up Peter. I don't have the air-con option and I don't have any issues with heating other than there could be a little more in reserve during winter. I do note that during heavy rain in summer with shorts on, you can feel spits of water through the cabin vents when on the move, presumably entering heater box from bonnet louvres.

That aside I have no reason to suspect the heater box drains aren't working as intended.

Richard, I would check that the drain tubes are not kinked or squeezed at some point.

Will do

Look forward to seeing the pic of your mod. The only spigots I recall on my Roadster are the redundant air-con evaporator feed points high up on left side of box.

There are spigots on the heater box in the engine bay and also under the dash but no tubes from memory. Some earlier mogs had tubes on the lower cabin spigots to vent via the bulkhead.

I assumed the spigots in the engine bay are drains, I guess they could be for the ac.
Here are mine on the passenger side . The airbox was removed in this photo.

Peter and John, a picture of my car whilst in build showing the spigot in John's pic (above heater hoses) plus two more low on left hand side of box towards rear - zoom to see. Apologies but now realise these have nothing to do with air-con fittings.



Parts book is no help in finding the heater box drain pipes. Do I need to look in cabin footwells Peter?