Largest 124 radiator.

[WDB124066]

Anybody know if there is a big option 124 radiator that will fit an AC Auto 320 car, maybe one of the Diesel radiators for example. I am getting sick and tired of a overheating car [even in winter now] so I wonder if fitting something that holds half the Atlantic will stop me twitching about the constant temp gauge fluctuation.
Alternatively does anybody know if there is a more efficient core that can be fitted to the existing tanks and hardware...

Many, many thanks, W.

 

[carat 3.6]

I use the w124 e300 diesel with a/c rad for v8 and turbo swap's, it is the biggest that is a direct fit.

 

[WDB124066]

God bless ya boy! Would it be too much trouble to ask for a part number...

And would anybody know [due to the Daimler parts rationalisation process or otherwise] if the replacement new Genuine rads are different in ANY way from the factory fit ones.? I have a strong suspicion that they are, just like the thermostats are.

 

[carat 3.6]

God bless ya boy! Would it be too much trouble to ask for a part number...

I'll see what I can do, but bear in mind to use one on a 320 the bottom hose is the other side of the rad so needs a long hose to reach it.

 

[WDB124066]

OK, with an alternative hose it is a straight swap in - no swearing..

Is there a ready made hose that fits or is it a matter of go finding one locally...

Sorry for so many questions carat but this whole overheating thing is just getting on my t1ts now.

 

[grober]

All your cooling fans working correctly? Viscous coupling kicking in at the right time? Remember this v8 cooling fan tweak? K6JRF Auto Page
Does the auxilliary Electric fan/fans kick in at the right temp- ie is their control circuitry calibrated and working correctly?
thermostat OK? Backflushed the existing radiator? examined it for cold spots- indicating a choked core ? dare say you have done all this???

 

[carat 3.6]

OK, with an alternative hose it is a straight swap in - no swearing..

Is there a ready made hose that fits or is it a matter of go finding one locally...

Sorry for so many questions carat but this whole overheating thing is just getting on my t1ts now.

There is no hose that is a direct fit, You need to custom make it.

An alternative to all this would be a custom alloy radiator if you want it to look stock?

 

[WDB124066]

Yes and this is why I asked about a more efficient core that could be fitted to the existing tanks....

A photo of an install of the diesel jobbie would be a big help in getting people's heads around it here carat. I can then get them focused on finding a hose before we go ahead and order what maybe a pricey item.

 

[carat 3.6]

Yes and this is why I asked about a more efficient core that could be fitted to the existing tanks....

A photo of an install of the diesel jobbie would be a big help in getting people's heads around it here carat. I can then get them focused on finding a hose before we go ahead and order what maybe a pricey item.

I'll see if I can get a pic for you. The pipe comes off the existing bottom hose, along underneath the fan cowling, and onto the radiator fitting.

If you don't want to modify the coolant pipes, it might be possible to fit the 320 end tanks onto the diesel core.

 

[WDB124066]

All your cooling fans working correctly? Viscous coupling kicking in at the right time? Remember this v8 cooling fan tweak? K6JRF Auto Page
Does the auxilliary Electric fan/fans kick in at the right temp- ie is their control circuitry calibrated and working correctly?
thermostat OK? Backflushed the existing radiator? examined it for cold spots- indicating a choked core ? dare say you have done all this???

Indeed I have grober. All the switching points are being seen to be correct on the car. Everything is working. Rad has been out, pulled apart and put back together again.

The V8 fan mod was considered but it makes it noisy all the time and it never used to need the VC fan much at all before the HG jobs & certainly not in winter.

I have had two head gasket jobs and we are at the point of thinking the HG may be covering some cooling passages a little bit and/or the debris from removing them [or sealant applied on refitting] may have found it's way into the system. That's why we took the rad apart to see = nothing.

Water pump was replaced, less than 40 000 kms ago

Thermo is new and is a lower temp one at 83 DegC not 87.

VC is new, all Genuine parts.

Bought the back flush kit from MB, backflushed before rad removal. Rad removal resulted in "this is the cleanest old rad we have seen Sir", baffle is in place, hasn't come loose. Fuel mix is correct. We are at a loss [and when I say we, some of the very best old MB techs you could ever wish for are baffled on this] so I am going to make the bold step of telling MB their parts are rationalised too much and fit a HUGE rad!

Problem is the needle is not stable, it is up and down all the time relying on the VC cutting in to bring it down or the over pressure electric fan to do the same. It has gotten to the point where it is spitting out refrigerant because it gets too hot, that drops the refrig pressure which then removes the overpressure triggered fan and we rely on the over temp electric fans - what a noise they make @ 107! They do the job nicely but that needle on the dash just goes up and down up and down all day. It does not want to stabilise and sit steady in traffic at all. Open road fine, traffic it just gives me the sh1ts.

I have even fitted new plugs in case they were the wrong ones. Mechs seem to think MB want the engine to run hotter, this is why they went to 87 thermo instead of 85 factory fit one.

If you guys don't mind having a head scratch on it for me I'd be ever so grateful, it only happens in heavy traffic. Open road it is perfect, sits at 83 irrespective of speed and ambient conditions.

Doesn't lose coolant, pressure tests perfect.

 

[grober]

Heavy traffic points to a lack of airflow rather than coolant capacity. In terms of hose modification could the same thing be achieved with two short flexibles and a fabricated st/st intermediate section [ a custom exhaust manufacturer /fitter might manufacture something to your design? Only othe rthing I can think of is some way of getting the hot air out of the engine compartment quicker?? vents /louvres undertray mods

 

[WDB124066]

Thank you very much for this grober, I hit some birds one day when out with some motorcycles and they have damaged the panel that sits under the headlights but above the bumper by tilting them inwards adjacent to the bonnet drops. This may have disturbed the airflow to the rad by introducing an air current at 90 degrees to the normal flow into the rad. Let me get that fixed - lens and panel. You wouldn't think it would make much of a difference but aero can be a funny thing. There is a large gap between the head light and the filler panel that will allow air to spill into the rad intake area at 90 degrees to normal flow. This may be having an effect...??

 

[Bellow]

Check also that air that has passed through the rad isn't being recirculated and making multiple passes through the rad.

 

[roadhog]

Allow me to throw in a couple of thoughts.

I'm in the middle of putting a 300d into what used to be a 300ce, looking at the two radiators there is no discernible difference other than the hose connections i.e. the end tanks. The core dimensions are the same on both. Mine are earlier cars than yours so not totally relevant to a 320 maybe but as far as I can see you won't gain much by going for a diesel radiator.

One difference I have noticed, my petrol car has two electric fans up front, the diesel only one. Both cars have factory fitted (Behr) A/C. The shroud around the twin fans covers most of the condenser radiator and therefore the cooling system radiator as well as it sits behind. The only airflow seems to be through the actual fans despite having slots in the bumpers. I have addressed this by adding some extra holes, as far as I'm concerned there can't be enough airflow.

There is also the shroud around the viscous fan to consider, if this is not fitted it pretty much renders the fan useless as it just swirls air around the engine bay rather than drawing it through the radiator.

Finally, on my daily driver, the temp gauge developed a fault whereby it would sit fine at normal operating temperatures but once slightly above it would fluctuate wildly all the way into the red despite the coolant temperature remaining stable. You describe an actual overheating situation so again maybe not too relevant to your issues but the gauges can and do go wrong but are often overlooked.

 

[grober]

WHAT ABOUT A RADIATOR RECORE WITH A HIGHER EFFICIENCY CORE?
Charles got his W114 recored by a radiator specialist for not a lot of money?

discussion of the various types here.
Upgrading classic Car radiators


[YOUTUBE]Itxd7kJuEX0[/YOUTUBE]

 

[carat 3.6]

I'm in the middle of putting a 300d into what used to be a 300ce, looking at the two radiators there is no discernible difference other than the hose connections i.e. the end tanks. The core dimensions are the same on both. Mine are earlier cars than yours so not totally relevant to a 320 maybe but as far as I can see you won't gain much by going for a diesel radiator.

The earlier car's have smaller rad size's than the later cars, a/c also makes a difference. The e300 Diesel is the biggest you can fit in a w124, it takes up the whole area. You even need to change the lower mounts to fit it in an earlier car as it is deeper than the original.

E320 radiator....

E300 Diesel radiator....

I think a custom alloy rad is the best option if you do need to fit a bigger one without modifying anything.

 

[hotrodder]

Carat's post makes this bit redundant but as i'd already typed it before spotting his reply... Mercedes webcatalog will get you MB and various other manufacturers part # for different rads... dunno about the e36 but it's the same two rads (with or without AC, 1245009003 with AC) for the 6 pot petrols regardless of body variant. IIRC rads for models with AC are a bit taller and wider but thinner to make more room for the condensor

There's drawings with core dimensions etc in many of the rad listings of the above link, google images is another way for example, 1245009003

Finally, on my daily driver, the temp gauge developed a fault whereby it would sit fine at normal operating temperatures but once slightly above it would fluctuate wildly all the way into the red despite the coolant temperature remaining stable. You describe an actual overheating situation so again maybe not too relevant to your issues but the gauges can and do go wrong but are often overlooked.

Temp gauge in mine has recently started misbehaving in this way too

You say the

Rad has been out, pulled apart and put back together again

Someone uncrimped the tanks, looked at the core/cleaned it and put them back on? Even if the ends of the tubes looked spotless and there was no signs of any blockages/silting a new rad would make more sense IMO. There's zero chance an old core will be as good at transfering heat as a new one due to years of oxidation and the like messing with heat transfer from the tubes to the fins to the air
What about the AC condenser? When i replaced the rad in mine the amount of general crud i got out of the condensor and from between the two was amazing

Problem is the needle is not stable, it is up and down all the time relying on the VC cutting in to bring it down or the over pressure electric fan to do the same. It has gotten to the point where it is spitting out refrigerant because it gets too hot, that drops the refrig pressure which then removes the overpressure triggered fan and we rely on the over temp electric fans - what a noise they make @ 107! They do the job nicely but that needle on the dash just goes up and down up and down all day. It does not want to stabilise and sit steady in traffic at all. Open road fine, traffic it just gives me the sh1ts.

I have even fitted new plugs in case they were the wrong ones. Mechs seem to think MB want the engine to run hotter, this is why they went to 87 thermo instead of 85 factory fit one.

If you guys don't mind having a head scratch on it for me I'd be ever so grateful, it only happens in heavy traffic. Open road it is perfect, sits at 83 irrespective of speed and ambient conditions.

Doesn't lose coolant, pressure tests perfect.

How hot does it actually get? How old is the rad cap? Their pressure stages commonly get weaker with age and they normally get forgotten about when pressure testing coolant systems as the adaptor to pressurise the system gets fitted in their place

There is a large gap between the head light and the filler panel that will allow air to spill into the rad intake area at 90 degrees to normal flow. This may be having an effect...??

Certainly not gonna help... my thinking is that sticking a bigger rad in it is treating the symptoms rather than the cause. If the problem is (as it sounds) related to air flow or coolant passages in the engine etc a bigger rad may not do much to help. If air can flow around the rad into the engine bay things can get screwed up both from air bypassing the rad and from air struggling to get out of the engine bay... some years back i helped a mate rod a Rover P3. Initially it had a pinto in it for budget reasons and ran hot until a decent rad & fan shroud was knocked up. Later he fitted a Rover V8 and temps went haywire. I suggested adding some lourves to the bonnet sides to let air out of the (now cramped) engine bay. 4 or 5 louvres per side transformed the thing, more stable coolant temps and no more overheating

If you still decide you want a bigger rad then like Carat i'd be more inclined to get one made, or at least look into it first... the standard MB rad is two rows deep IIRC, my 'go to' core when i make a rad is a large single row design (usually from Pace Products). Instead of two small smallish tubes it has one much deeper tube giving more surface area without making the core itself much, if any, deeper. Be aware that a one off custom sized core ain't cheap (well maybe better value compared to MBs insane rad prices)... last rad i quoted for was for an old Maserati Quattroporte, core size was 630mm tube length x 400mm stack height x 45mm thick and the core alone was nearly £300. Fiddly LH tank shape on a 320 and while the RH tank is a simple shape gotta make a transcooler loop to go in it hence i just bought a Nissens rad for mine- 1/3 the price of a custom UK made core and i didn't need to make anything

 

[coupe addict]

I believe that ac fitted models have two plastic fairings at right angles to the rad running alongside the engine, which are not fitted to non-ac models: I've always wondered if these were a contributory factor in making my non-ac 320 coupe run cooler than its ac predecessor.
Removing the panels is a two minute job, so an easy experiment, but if my guess is right it may make the ac less efficient.
Only a palliative, of course, but any port in a storm....
Steve

 

[grober]

Two other possibilities.
Cracked plastic expansion tank [ they go brittle with age] or a dodgy new water pump- impeller is often plastic push fit on shaft and can "spin" slower than it should.
M104 overheating seems to be quite common? 1994 E320 m104 running HOT (yet another) - Mercedes-Benz Forum

 

[WDB124066]

Water pump was new about 40 000 kms ago we have not had it off to see it's condition since.

Radiator was new at the same time and is why it is very clean not even the white powder corrosion is existant that you often get with Al

Car uses no coolant so I don't think it is a problem with cap or expansion tank, - or leaks in general. It doesn't smell of antifreeze at all when in Garage after a good run. It also holds pressure on test very well so tank is almost certainly good to go. Water does leak out of water pump when on test but that is at quite high pressures.

All debris is out of the rads and quite some debris does collect so you are spot on for suggesting it. I have it cleaned once a year and when the rad came out to be pulled apart they did it again but didn't find much. I have made a SS wire screen to keep the bugs out that gets fitted when travelling intercity in the summer, keeps the flys out. Works well. Gets taken off in city traffic and in winter it isn't needed.

Anti freeze conc is correct. Genuine coolant AF in the system.

Yes the M104 does appear to have an inherent overheating problem when they age as this is the third one locally [one being a 280] that has everything sorted but it still overheats. Exactly the same symptoms accross all three. All three have had HG's done recently!??

Things are not helped my MB introducing a hotter thermo for these either I might add.

Let me get that small amount of panel damage sorted and we can have another look at things from there I'd say.

Oh air is removed from the system out the back of the engine bay in the usual way - nothing has changed in that area since it was rock steady at 83 back in the good old days before the first HG job.