Welwynnick

I think there's no doubt the Davies Craig would be a good pump, but there's a few things that point me towards the Meziere WP136S or Johnson CM90.

Because this is a modification, I think its best to tread in someone else's steps - in other words, use a proven route to achieving what you want. Let other people find out the pitfalls for different potential solutions where you can. Meziere and Johnson aren't totally without their issues, but they're widely used and fairly well understood.

My impression is that the Davies Craig 80 and 115 pumps are intended as replacements for engine pumps. They have high-flow characteristics: shallow pressure/flow curves and large ports. I think the charge cooler circuit isn't like that - its higher resistance and lower flow. There are two, small heat exchangers, and the pipes are small. The EWP80/115 aren't auxilliary pumps, whereas Bosch, Meziere and Johnson are intended as aux pumps. They make other models for engine cooling.

Davies Craig do make a couple of specific auxilliary pumps, the EBP and EBP25 (which looks suspiciously familiar) but they doen't flow very much. However, they do have 3/4" connections

The EWP80 & 115 have large inlets and outlets, which are suited to engine cooling. All the auxilliary pumps have 3/4" connections, which makes life easier for us.

What's really interesting for me about Davies Craig is the pump controller, which gives a us a better option than the Mercedes ECU. I think that might be really worthwhile, and not necessarily with Davies Craig pumps. It could be considered as an independent option to the pump itself - something to add after upgrading the pump, or even to be used with the stock pump, as an effective alternative to changing the pump.

Davies Craig pumps seem to be well-distributed around the World, but I think I would go for a WP136S or CM90, there's no great problem with importing from the US. I've done that with lots of electronics and car parts with no issues.

Nick

BenzBoy12

Great thread, lots of good info here. Everyone looking at cooling mods for a V12TT car should read this.

Crissus

https://mbworld.org/forums/w211-amg/...-vs-wp136.html

Highly Interesting!!!

So the weakest one, reduces the best?

Welwynnick

Rather than side-track this thread, I started a new one in the generic (and lesser-read) M275 Forum, and developed it a bit further:

https://mbworld.org/forums/m275-v12-...ion-pumps.html

Cooling systems are quite complicated and difficult to analyse and predict; not pretending that I'm there yet, but I am scratching my head as to why the Meziere should give higher IATs.

Nick

Mackhack

There are many resellers of Johnson CM90, EWP-80 or EWP-115 (which requires a new cooling hose/pipe system because it moves so much water your inside resistance becomes so large you won't be able to use the additional water throughput possible).

If you need websites let me know and I'll look it up if I have some time. I'm either going for the EWP-80 or Mezzire WP 136 after I install my new Eurocharged pulley so my additional power can efficiently be used.

Mackhack

Yes you can use the EWP-80! I'm about to buy it, too.

Welwynnick

In general, I wouldn't recommend ANY of the Johnson, DaviesCraig or Meziere pumps for IC duties. They are all optimised for engine cooling rather than IC cooling.

Engine radiators are large, and the cooling circuits are high flow and low resistance.

Intercooler systems have two small, high-resistance, heat exchanger in series, and they're characterised by high resistance and low flow. In fact, if you really want more flow, you're pushing the boundaries of what centrifugal pumps normally deliver, and you have to move to positive displacement pumps. The EMP pump is about as good as it gets there.

To get performance, reliability and value for money from a centrifugal circulation pump, you need to match the system curve (pressure vs flow curve) to the pump. A pump will have a nominal operating condition, a "sweet spot", where the pump is most efficient. That's the operating condition that the pump is designed around. Operate it too far from this condition and you won't make the most of it. Output won't meet its postential, and you increase the failure rate due to various fault conditions. These will typically damage the bearings, seals or motor, maybe even the impeller.

If you use one of the engine cooling pumps I mentioned, the pump will be working against too much resistance and will be turning too slowly. The pressure in the annular chamber around the impeller will not be equally distributed. This means there will be an excessive radial thrust on the bearing, and a once-per-blade-pass load on the motor. There will also be an increased axial load (end thrust) on the impeller. The output flow will be low, the pump will be noisy, and the bearings and seals will fail quickly.

Much better to use a pump that's designed for IC systems.

Regards, Nick

vee12

Is a pump like the EMP WP29 just overkill? Seems to be able to handle high pressure (resistance) AND has high flow characteristics. Thoughts/opinions from the experts?

Mackhack

Get the EWP-80 with your stock hoses and pipes, get the EWP-115 if you're planning of replacing your heat exchanger for system that has a bigger diameter system.

Welwynnick

Here's how all the popular IC pumps compare.

The key parameter is where the pump curves (coloured) cross the system curves. The steep system curve represents a typical IC installation like MB, Caddy or GM, and the other represents a notional low resistance IC system. The WP29 is by far the best pump, as long as you have it programmed to run at full speed. The Johnson, DaviesCraig and Meziere pumps are relatively poor performers when installed in an IC system.

grane

Can one install a CL65 radiator in a CL55 of the 215 body style? Would hoses and fittings need to be changed? I reckon the mounting hardware would anyway.

How much would this help the cooling of the entire system? Would this obviate a larger intercooler? BTW the intercooler on my CL is larger than the E55 stock intercooler based on visual examination.

Has anyone tried this radiator swap?

vee12

Concerning the EMP WP29, are there issues with the MB electrical system/wiring handling the current draw? Could you wire it to just run full time when the ignition is on? I understand this is not a "plug and play" installation, but it seems to be worth the effort. BTW, I already have a larger Eurocharged HE installed, and presently running the wimpy CM30.

Welwynnick

Do you mean the CL65 engine radiator? That's the same 40mm radiator used in the other large-engined cars (though it doesn't use a radiator with the small air inlets). The small engined cars use 22 or 26mm radiators.

The CL65 uses a 40% larger IC heat exchanger, and I guess you could use that. However, the CL65 has a different air con HE, so you might need to use that, too.

Nick

Welwynnick

The WP29 has a much higher current draw than stock, so you'd need thicker wiring. The pump is powered through a relay, so check the rating of the one that's installed. Its the middle of the three relays in the aux fuse/relay unit behind the partition, next to the RHS relay box.

Nick

Darin Schnoor

8.5.2Bumping an old thread here, hoping for some advice/experience. During my E63 bumper swap I found that 1) the fuse for the IC pump was blown (and was incorrect at 7.5A), and 2) the PO had installed a Meziele WP136 and wired it to be ON with IGN, and 3) the WP136 appears to be seized/inop. I bench tested it with 12V and there's a slight thunk from it when power is applied, but it does not spin.

I already have a Bosch 010 pump ready to go, but in order to install the WP136 the PO shortened the inlet hose, replaced the wiring plug, and removed the factory pump hanger/clamp. So going to the 010 will take a bit of work (especially the plug part).

I'm running a VRP H/E and considering making it a split system. I've read conflicting info on whether the WP136 is "too much" for systems w/o a large reservoir tank, and the debate seems inconclusive from what I can read. I'm running a 76mm pulley and RaceIQ tune but otherwise power is effectively stock.

What would you choose in this situation? WP136 or Bosch 010?

Mackhack

I would go with a CWA100 and an adapter cable from me.

FYI: the M113ML comes already “split cooled” by the factory.

Mezier and Johnson pumps are junk, sold for a long time for 500-1000% markup by tuners.

Bosch old and new one are junk. They are rated for about 30k km max then die.