V12Godspeed

I installed my rear trunk tank reservoir over the weekend. Car feels way more responsive and its amazing what IAT's will do to these V12's. I also switched pumps to a Meziere pump and jumped it so it's on at all times. I will put up pictures but see the schematic for a summary of what I did. If I did something wrong please feel free to correct me. Thx

Remember the idea is for the IC's to get the first shot at the Iced Water.

shardul

iTrader: (1)

did you get rid of the filler cap between the IC

V12Godspeed

Nope I didn't. Why? Isn't that part of the whole system?

Welwynnick

I think running the pump all the time is a big win, as long as it doesn't cavitate. You don't have to wait for the IC system to START cooling when you give it the gas. It also keeps the temps as low as possible, rather than sufficiently low.

The picture is for the Maybach: do you have your pump betweeen the HE and the trunk tank?

Nick

V12Godspeed

Yes, this is the maybach one. Couldnt find one for the 65. My pump is in stock location. I nipped the hose at the end of the Heat exchanger, same thing as the picture above only opposite.

RaceHorse

Hey, every bit helps when summer is here, glad it hasn't been as hot as the summers of the past. Are you still running stock intercoolers or did you swap them out at the same time? I know you have a few other things going on right now, but did any other mods make it on the car yet? Enjoy!!

V12Godspeed

Hahah, I have an arsenal just sitting in my garage. I made the appointment to swap turbos around middle of Sept. I moved to FL and the heat is brutal. Car was sluggish so I decided to just give it better cooling. I will soon install the IC's and everything else.

leodangelo

OK,

I have a "dumb" (or two)...

1) Do you run ice in these tanks?
2) If so how long does it last?
3) Do you have to remove fluid before adding ice?
4) With all of this going on in your trunk does it make a mess?

Thanks in advance for the information.

-LeoD

V12Godspeed

No dumb question, for 1- yes I put Ice for track use only,
2- it lasts about one run down the 1/4 strip
3- yes, have to dump the hot water after the run and refill to cool off, and then one last time to preserve the Cold temps before another blast.
4- No mess if you know how to do it neatly, its only water.

Now, I do not have the need for Ice anymore since I bought a Kincaid killer chiller. It's like having Ice 24/7 365 days a year. Specially in Florida where you use AC every day, every night. Hope that helps.

Thericker

Way to go brother! That's not an easy install when fishing all the 3/4" hose from trunk to front HE etc

shardul

iTrader: (1)

yes it is. some people get rid of it since the system is filled from the trunk tank and it is self bleeding.

V12Godspeed

What I do for that is remove the rubber ring on the rear tank so air has the chance of escaping. Just not fond of leaving something open in the engine bay even if its water. Thanks!

V12Godspeed

Thanks Sean, just trying to get my hands dirty for a bit.

Welwynnick

Even with a trunk tank, the IC certainly isn't self-bleeding.
The additional plumbing to the tank mustn't take an appreciable down turn anywhere, otherwise it will create a partial air lock.
All the W215/W220 heat exchangers have major built-in air locks that can only be bleed using a vacuum filler
Although you can bleed the intercooler intlets using the fill valves (with difficulty), the outlets still have air locks.
Its a terrible system. I use an engine radiator HE that bleeds from the top, and a swirl pot / header that bleeds from the IC inlets.
I think the only alternative is a proper vacuum filler(and I don't include the MB filler when I say "proper" - I mean real vacuum, like an AC vac pump.)

Nick

shardul

iTrader: (1)

on my 2 x front mount heat exchanger setup I have to take it to a MB tech to vacuum bleed it each time I work on it. I tried all the coke bottle etc etc ways but that never worked for me

Dr Matt

I've been thinking about buying a vacuum bleeder like this so I can do it myself.



Given the quality of work done on my car before I got it I would bet there is air in my system already and when I add the Killer Chiller this winter I'll need to bleed it anyway. I figure it is cheaper to buy the tool than pay the dealership to do it twice.

Welwynnick

That looks equivalent to the MB bleeder. Its a compressed air vacuum filler (quite an upscale one, actually). I'd say that you guys really ought to get one, but I'm not convinced it would do the job. Maybe it does, but those vacuum pumps only generate 80-85% vacuum.

To get all the air out of the secondary cooling system, you really need about 99% vacuum. Positive displacement pumps don't really go that high, so that leaves single stage rotary vane vacuum pumps - the oil filled type, like AC pumps. They go down to a few Pascals, and the popular Chinese ones cost under $100.

Like a lot of established electrical, pneumatic and hydraulic technologies, they're problems that were solved long ago, and are now commodities. No need for expensive solutions. I hope to have a few other easy solutions to our other problems soon.

Anyhow, I'd say give it a go; Mercedes may know something that I don't.

Nick

Dr Matt

Looking at the design of the intercooling system, my biggest concern about air is the front heat exchanger. Since the inlet & outlet are both on the bottom, there is absolutely no way to get all the air out of it without a vacuum fill system. I believe you might get all the air out of the intercoolers by running the system for a while, but the whole system is flawed for self bleeding due to the heat exchanger outlet location.

If I ever have reason to pull the front of my car apart I'll be looking into adding a bleeder valve at the top outlet side or having the outlet relocated to the top of the H/E by a local radiator shop. I might just do it this winter anyway when I add my Killer Chiller since I'll be draining the system anyway. Probably cost less than buying a tool and from then on it could easily be bled by just running the pump.

In also supect the reason people see a big improvement when they add a second H/E is that most aftermarket H/E's are self bleeding (outlet on top of outlet side tank) so that even if they have a useless stock H/E because it is 1/2 or more full of air, the secondary added one is actually working properly.

Welwynnick

There's a lot of issues there.
I learned a lot about pumps and cooling systems in the last year or so (see sig).
Cooling systems have been developed over a hunderd years, its a problem that's been solved.
However, Mercedes seem to have forgotten all about it with the V12TT, and treated it as a special case, which is very unfortunate.

There are some long-established golden rules for installing (centrifugal) pumps, including:

• The pump inlet pressure should be as high as possible.
• Therefore the pump should be located at the lowest point in the system.
• Locate the pump after the radiator, to keep it as cool as possible.
• Mount the pump horizontally, to minimise bearing end loads.
• To avoid air locks, the outlet should be at the top of the pump, and must not point down.
• The pump's pressure/flow characteristics should be matched to the system resistance curve to achieve best performance.
• Don't run a pump into an excessively high or low resistance, or it will fail quickly.
• Keep air and contaminants out of the system.
• Finally - feed the pump from the BOTTOM of the radiator, to minimise air ingestion.

It's the inlet that should be at the top of the HE (but maybe that would interfere with the LHS engine air intake on the V12TT). Either way, there ought to be a bleed facility at the top of the HE, whether its an automatic bleed to a header tank, or a manual bleed port like the end of the return pipe (near the ABC pump).

But yes, people often see an improvement in the performance of their IC system simply because its been bled properly, rather than because of the modifications they've done. I can't think of any other reason for the popularity of marine circulation pumps and engine cooling pumps.

Regards, Nick

shardul

iTrader: (1)

Welwynick is the man when it comes to cooling

V12Godspeed

+1 Sure is!

I datalogged my car a few weeks back in stop and go traffic and temperature did not go any lower than 156, highest was 172 in this 85 Degree weather. Once I install the killer chiller we will see where they end. Anything above 130 and you are toast when it comes to power.

shardul

iTrader: (1)

what about a small shot of H20 post IC to keep thing cool without messing with the octane rating which comes with the use of methanol

Alex L

Would be interested in seeing your results. Found KC to be not as effective when paired with Weistec blower and rear tank.