Charge Cooler coolant overflow

[Ginger pig]

All,

I took the SE for a run down the road and upon my return noticed that the coolant from the CC header tank was flowing quite well from the overflow pipe at the top. I have not topped up the coolant for about 6 months and; in fact thinking back, it leaked a little the last time I drove her a couple of weeks back. The CC itself is not cool but only midly warm and seeing as the car has been a non runner for around 6 years before I owned her; I can only assume that at some point soon I will need to replace the pump; however did not think that this coolant issue would be simptomatic of a corroded pump.

What is the most likely cause of this overflow?

I would appreciate any input.

[dodge1979]

Mark, think we talked about chargecoolers last time I saw you last year? I did mention converting to an electric pump as the way to go...as for the overflow of coolant. I have just the single header on my s4, yours is the twin type? As the outlet from the chargecooler to radiator is next to the bleed hose, which is the one you talk of, they share the same chamber inside the chargecooler unit, under the filler plug. As the coolant flows through the cooler and out, a certain amount will flow down that route to the header tank.i woukdnt worry about that. The main concern is the fact its not cold. As mentioned, change to an electric pump. It cuts out any hassle and is more reliable/ efficient.if you have a radiator issue...youve stilk got. The spare rad? Eventually if you have an air lock in the system, it should bleed out. My money is on changing the pump as we previously talked. Youve got my number, give me a call if you like. Darren

[Vulcan Grey]

The chargecooler reservoir cap is a pressure cap... might not be holding pressure correctly.

Then again, I'd guess that your pump definitely isn't working as well as it should.

[Ginger pig]

Thanks guys,

Quick update: checked the CC header tank and that was completely dry......last time I checked it (around 2 weeks ago when I last ran her) it was completely full!

[Bibs]

The top of your cc should be cold after a run, as cold as a beer from the fridge. If your pump isn't working, the water that's in there is being heated up by the air passing through it and no doubt boiling the water and it's pressurising the system and leaving as vapour under pressure.

Get an electric pump, you're losing out on 40+ bhp right now!

[mr.oogieboogie]

after purchasing the chargecooler rebuild kit (which i still have) i decided to blank it of and put in an electric pump , i used a pump from a jag xjr which is also used on 7 series bmw's. got off ebay i think i paid about £30 for it and also about £5 for new pipe as the inlet / outlet were a bit larger on the pump. the flow rate is good and its wired so it comes on when the ignition is put on, to bleed it i jacked up the back of the car and slowley poured in coolent, then i connected it up and ran the pump for a few seconds then topped it up and it bleed itself quickly., i used the alloy pump end and had it welded up then i refitted it minus the shaft and the impellor, if you go this way remember the rubber washer otherwise you will leak oil , to access the chargecooler pump you will need to remove the oil filter so you may as well schedule it in when its ready for an oil change,

the impellor on mine looked in as good condition as the new one but on inspection the rubber had come away from the brass center so any pressure on it and only the center rotated rendering it usless, mine went dry due to the front pipes being caught by the tyre on full lock, looks like the pipes had been bent forward causing the rubbing.

[Ginger pig]

Will it hurt the car to run it over the next couple of weeks with a dry CC system?

[Bibs]

Yup, you'll blow your car right up*.

*May not be true. You'll be fine - just change to a 'leccy pump when you're ready and expect to be going slower than you should be!

[Ginger pig]

All,

I have now replaced the CC Pump on the SE, flushed through the system but I am still getting a lot of coolant loss from the CC header tank (smaller of the two) through the over flow pipe. Would you expect this as the system balances itself out or is there still an issue here? I will connect a hose to the CC inlet and I would imagine that this would then overflow the header tank if there are no blockages. When I ran the system up after replacing the pump; I did it in accordance with the manual by just filling the header tank initially and then topping up as it went down. Do I need to bleed another way? Your advise and thoughts would be appreciated.

[dodge1979]

If your about at the workshop sunday I could drop by with my chargecooler filling gadget I made for you to borrow? It makes it.bloody easy....no coolant spillages etc..cant do beforehand as im moving tomorrow im afraid.

[Ginger pig]

Thanks Darren,

Only just picked up your post!

With regards to the CC; I have just realised that I had merged the two systems..... there is a very similar hose which leads to the T piece behind the turbo. I had swapped the CC outlet hose with that. Only realised when I purged that hose with a hose pipe and notice it overflowing the main header tank.....Doh!!!!!!!!!!

Still cannot get the CC down to a nice temperature though...... Any thoughts?

[dodge1979]

well, your using a mechanical pump, you I remember you saying you had bought the refurb kit a while back, so I assume its the refurbed one? Also, how good it the rad...and did you flush the system out? then refill with fresh antifreeze coolant mix...I run mine with the same as the engine coolant, 33%ish and mine runs Ice cold...but I am running a super custom rad though....maybe youve still got air trapped in it somewhere....

[Ginger pig]

Hi Darren, Flushed the system through totally until there was fresh water coming out of the system and radiator..... alot of crap came out first (very brown). The pump was pulled from the project as I will go electric for both and thought this would be an interim solution for the maroon SE. Bleeding the system is quite messy. I filled the CC header tank and then started the car. I then raised the back of the car with a jack and then cracked open the CC nut on the top of the cc and let air (and a lot of coolant) out whilst topping up the CC header tank. CC felt very hot to touch which cannot be good!

[dodge1979]

It is messy that way...but I have the solution that will enable you to do it neatly and not waste a load of.coolant! If you want a hand im happy to help, free sat afternoon at the min if your about or one eve this week..i dont mind poppin in on the way home.

[Ginger pig]

Hi Darren,

That would be great if not to much hassle?

I will be at the unit on Saturday early afternoon.

[dodge1979]

Ok, depends wat time I finish work sat, but ill drop you a line when I do to check ur still about..

[Glyn Wise]

Hi all,

Can anyone confirm that the bleed nut on the chargecooler unscrews anti clockwise?

If so I could be doing a bit of swearing tomorrow its stuck solid,ive got the cc off and

left it soaking in Rostoff ice.......could be a bugger.

Cheers Glyn

[sailorbob]

Yes, it is a normal thread on the chargecooler bung.

[Glyn Wise]

Cheers ol pal

[mr.oogieboogie]

I used a big pair of stilsons on mine as it's quite soft and can round. Once off put it back with a bit of grease on the threads

[Bibs]

They are obsolete and a pig to find a replacemnt, take it easy on it!

[dodge1979]

Its a standard thread size, cant remember off the top of my head what, so it shouldnt be hard to have one made or find a plug from a hose or hydraulic specialist in worst case..stripping the thread in the cooler would be worse surely? Mine was bugger tight too, but then it suddenly went free with enough leverage...maybe its a combination of the two different types of materials heating and cooling at different rates causing it, or a previous owner using thread lock..or just its never been undone or for a long time at least..but as mentioned be carefull not to round off.use a flat sided socket instead of a spanner to be safe maybe...

[Glyn Wise]

Well its in tighter then Ken Bruces wallet,so ive driilled and tapped an M10 hole in the bleed nut M10 bolt inserted with a copper washer with a dab of copper slip,its had a good flush out.

May be a bit of a bugger to top up but at least nothing broken.

Edited April 13, 2012 by Glyn Wise