Best Access to Condenser Port???

[Artermis]

Morning all,

need some advice on how best to access the upper condenser radiator port on my 190, please.

Stupidly the air-con hose that runs from the compressor to the upper port on the condenser has worn a hole in itself by rubbing on the compressor pulley!

Seems a bit of a design flaw that...

The connection on the compressor is easily accessible enough but what's the best way of getting to the upper port on the condenser. It looks like the port is just next to the headlight behind the bumper fairly high up the top.

I can't see an access panel but wondering if the upper cross member can be unbolted or something like that, rather than having to faff taking the entire bumper off.

What's the advice for you good experienced folk?

Cheers, Ben

[SD1too]

You’ll have to take the bumper off I’m afraid Ben (but that’s easy compared with what I’m doing at the moment).

Note that the MGR diagram erroneously shows the condenser connections transposed so this applies to Rimmer’s diagram as well. The hose assembly you need is JUF 000581 which is rather expensive!

An attractive alternative, which I used many years ago, is to get your local Pirtek depot to crimp a new hose to your existing fittings.

If you buy second-hand, make sure that the part is scrupulously clean before fitting.

You will need two new ‘O’ rings, JUU 000 010.

On completion I recommend the use of a local independent mobile air conditioning practitioner who, if he is any good, will agree 30 minutes’ evacuation (to remove moisture stored in the receiver/dryer) whilst he drinks the cup of tea you’ve made for him. The fast-fit boys will only do 10 minutes because they need to keep busy selling exhausts, tyres and brakes.

My advice is based upon replacing my own condenser last year.

Simon

[Artermis]

Originally Posted by SD1too

You’ll have to take the bumper off I’m afraid Ben (but that’s easy compared with what I’m doing at the moment).

Note that the MGR diagram erroneously shows the condenser connections transposed so this applies to Rimmer’s diagram as well. The hose assembly you need is JUF 000581 which is rather expensive!

An attractive alternative, which I used many years ago, is to get your local Pirtek depot to crimp a new hose to your existing fittings.

If you buy second-hand, make sure that the part is scrupulously clean before fitting.

You will need two new ‘O’ rings, JUU 000 010.

On completion I recommend the use of a local independent mobile air conditioning practitioner who, if he is any good, will agree 30 minutes’ evacuation (to remove moisture stored in the receiver/dryer) whilst he drinks the cup of tea you’ve made for him. The fast-fit boys will only do 10 minutes because they need to keep busy selling exhausts, tyres and brakes.

My advice is based upon replacing my own condenser last year.

Simon

Yeh that's the correct hose alright. Wasn't expecting that price haha.

I'm still hopeful of picking up a second hand good part but Pirtek is a good shout if I can't find one. I think Andy Willi has what I need though, which is good.

Was already planning on replacing the o-rings. I've got one of those multi-compartment boxes in the shed full of loads of different sizes, so hopefully I've got some in there the correct size to replace. They just go brittle on AC lines so yes, definitely replace!

Was really hoping to avoid the bumper off experience in exchange for a simpler solution but looks like it'll have to happen if that's what's needed. Always a risk with AC parts that they're utterly inaccessible.

Thanks for advice, Simon!

Cheers,

Ben

[T-Cut]

If the refrigerant gas has been lost completely for more than a day or two, you're best advised to replace the desiccant pack in the condenser. This contains silica gel, which absorbs traces of water in the system.Once this has saturated it's useless. I guess it might regenerate by baking it a few hours at 120C or so but that may not be feasible.

TC

[SD1too]

Originally Posted by T-Cut

This contains silica gel, which absorbs traces of water in the system.Once this has saturated it's useless.

Over the years I've had air conditioning systems devoid of refrigerant for considerably more than a few days and I've never experienced any adverse effects after recharging. Maybe it takes more than a typical leak to reach the level of saturation you refer to. I'd say that the risk isn't significant from a purely practical point of view.

The text books say that holding "a vacuum" lowers the boiling point of the stored moisture enabling it to be extracted by the specialist equipment. Do you not concur with that TC?

Simon

[T-Cut]

Originally Posted by SD1too

The text books say that holding "a vacuum" lowers the boiling point of the stored moisture enabling it to be extracted by the specialist equipment. Do you not concur with that TC?

The text books are correct for water in a free state. That is, water as you know it, surface wetness, or minutely dispersed within the refrigerant (flurocarbon liquid). When this 'free' moisture is absorbed by the desiccant filter it produces hydrated silica gel, where it's in a completely different state. There's no vapour pressure when bonded in the solid phase. So, you can't dehydrate silica gel by applying vacuum, believe me.

For example, the most common dying systems used in labs are silca gel vacuum desiccators. This is typically a heavy duty, sealable glass container with a load of silca gel in the bottom. This is evacuated with a pump of some kind.



You put the sample you wish to dry inside and evacuate it. The pressure is reduced to effectively zero gauge. Over several hours, the low pressure causes moisture in/on the sample to evaporate and migrate into the silica gel. Once bonded as the hydrate it stays bonded. A colour changing compound is usually combined within the gel to provide a visual indication of saturation level. When hydrated, the gel has to be regenerated thermally. This system also applies to other regenerable desiccants like certain anhydrous salts, zeolites and molecular seives.

Silca Gel and Regeration: https://en.wikipedia.org/wiki/Silica_gel#Regeneration

Hope this helps.

TC

I'd suggest the essential purpose of evacuating an aircon system is to remove all air and any moisture that's physically contaminating the pipework, compressor, evaporator, etc. But the desiccant trap won't be affected.

TC

[grivas]

Originally Posted by T-Cut

The text books are correct for water in a free state. That is, water as you know it, surface wetness, or minutely dispersed within the refrigerant (flurocarbon liquid). When this 'free' moisture is absorbed by the desiccant filter it produces hydrated silica gel, where it's in a completely different state. There's no vapour pressure when bonded in the solid phase. So, you can't dehydrate silica gel by applying vacuum, believe me.

For example, the most common dying systems used in labs are silca gel vacuum desiccators. This is typically a heavy duty, sealable glass container with a load of silca gel in the bottom. This is evacuated with a pump of some kind.



You put the sample you wish to dry inside and evacuate it. The pressure is reduced to effectively zero gauge. Over several hours, the low pressure causes moisture in/on the sample to evaporate and migrate into the silica gel. Once bonded as the hydrate it stays bonded. A colour changing compound is usually combined within the gel to provide a visual indication of saturation level. When hydrated, the gel has to be regenerated thermally. This system also applies to other regenerable desiccants like certain anhydrous salts, zeolites and molecular seives.

Silca Gel and Regeration: https://en.wikipedia.org/wiki/Silica_gel#Regeneration

Hope this helps.

TC

I'd suggest the essential purpose of evacuating an aircon system is to remove all air and any moisture that's physically contaminating the pipework, compressor, evaporator, etc. But the desiccant trap won't be affected.

TC

That is correct no amount of vaccum is going to dry the desiccant in the trap, once 'wet' it will need replacing, in the case of such as those found in a typical organic chemistry lab, it will need heat to remove water before reuse.
So if the desiccant trap is in need of replacement are these available, and how would we know if indeed they need replacing.
Also can anyone please remind me is the condenser in front of the fan , before the radiator or is the radiator in front of the fan, and how can you tell if condenser is good.?

[T-Cut]

Originally Posted by grivas

- - - - can anyone please remind me, is the condenser in front of the fan, before the radiator or is the radiator in front of the fan, and how can you tell if condenser is good.?

The condenser is mounted on the lower front face of the engine radiator and the fan sits in front of both.

The condenser fitted to the 75/ZT range suffers weathering/degeneration of the cooling fins. Visually, it will probably appear OK, but a stroke of your finger across the matrix will remove most of it as crumbly fakes. Without enough fins, the condenser will not run the system properly and it will over-pressurise/shut down.

TC

[grivas]

Originally Posted by T-Cut

The condenser is mounted on the lower front face of the engine radiator and the fan sits in front of both.

The condenser fitted to the 75/ZT range suffers weathering/degeneration of the cooling fins. Visually, it will probably appear OK, but a stroke of your finger across the matrix will remove most of it as crumbly fakes. Without enough fins, the condenser will not run the system properly and it will over-pressurise/shut down.

TC

So looking from the front of the car, through the grill and the fan blades the radiator you see is the coolant radiator, or the air con radiator?

[SD1too]

You see the condenser Mario.

Simon