DS Cooling

DS cooling

Pottsy,
From one who knows nought of Citroens. Would the position of the number plate be detrimental?

Being more familiar with Peugeots [old ones] I know of owners who have played around with caps, thermostats and locked up fan blades when all along it has been a blocked radiator!

"Is the prisoner bound?" "I know nought of his health sir".
 
I don't think the numberplate would affect it. If you look at a picture of the DS there is no grill or air pickup in view. It's actually under the nose. You have to crawl under the car to see it.

seeya,
Shane L.
 
Besides which, I've even augmented the air flow a bit by drilling the access hole for the crank handle through the number plate!

Weally Centuwion! I'm supwised to see you wattled by a wabble of wowdy webels!

About Half Past two Sir!
 
pottsy said:
Brett

Thanks for the input. Yes, to a point I agree with you, I don't think I've got a huge problem any more, and after all of the work I've done I should bloody well hope not!

However my main concern is with the apparent fact that driving on the highway on an averagely warm day (OK, Yesterday was close to 30C, but the point remains) the fan is still being cycled in and out. This says to me that the airflow reaching the radiator at speed is still fairly minimal. I've driven (conventional) cars before that would boil their heads off in traffic, but run at normal temperature on the highway, due primarily to the 100Kmh wind doing the job that the fan wouldn't or couldn't do. It may be as you said that even at 100Kmh the airflow is close to zero in which case, yes, the fan is doing its thing satisfactorarily. It still seems odd, however.

My only concern is that if I encounter hot weather on the Peugeot Re-Run in April/May then things could get sticky. I will be carrying the engine driven fan and may bolt it back on if things get bad.

I may have hit on a partial solution by creating a temporary lip spoiler out of a sheet of flexible rubber and some gaffer tape. (see photo). A run in normal traffic this morning seems to indicate that this is supplying some kind of airflow. The temperature would lower to normal as soon as I was flowing with the traffic. Yet to be tested at 100Kmh, however.

It's possible also that the addition of the under tray (other photo) that I made yesterday will improve the airflow characteristic. There seems to me to be a larger cross sectional area for the hot air to exit past each side of the motor than there is cross sectional area of the intake duct, so perhaps the under tray assists in directing the air along the desired path.

Only time will tell!

Pottsy.
Click to expand...


I had a similar problem with the V6 505 I built up.
Even going down hill on a cold night on an open road the viscous fan cycles on and off.
All manner of shrouds, fans, cleaning of radiator, changing to electric fan, engine change has not fixed the problem. In competiton the car is OK although the fan of course still cycles on and off.
I've got to believe that there is a problem with the air flow. Next thing to try is fitting the plastic shield that goes under the anti roll bar on the late 505s. This car was a GR and didn't have this fitted.
Graham
 
DS cooling.

Potsy,
Are your fans [electric] turning in the right direction, wired up correctly?

Graham,
Have come across "vicious" fans/hubs fitted incorrectly, blowing instead of sucking! Not on any Pugs though.
 
Wildebeest said:
Potsy,
Are your fans [electric] turning in the right direction, wired up correctly?

Graham,
Have come across "vicious" fans/hubs fitted incorrectly, blowing instead of sucking! Not on any Pugs though.
Click to expand...
Not in this case and anyhow, when the fan comes on the engine temp comes right down.
Graham
 
What about a back to front bonnet scoop? I recon that'd look fully sik!
 
overheating....

Hi potts...
I had a similar problem with my first car. The spark plugs were too hot in the heat range department. I'd make sure that the plugs you are using are actually the correct heat range, as the difference that makes is a major player. ( Or was in my case).

There must be something obstructing the air flow. I heard that in England they block off about 1/2 the air duct to restrict the air flow, so they warm up sooner.
My DS 21 hydraulique had standard 1968 air ducts and never ran hot. There was no restriction under the car either for air to escape. Make sure the air can get away beside the motor on both sides.
I just thought of another thing.......
How does it run???
Have a real good look at the distributors position.
One of my cars once had a ridiculous overheating problem. See if your distributor "looks" to be in the proper place, as it's possible that someone has removed and re-fitted the distributor ...as mine was...but out by one tooth!!!
This made the car retarded, even when the distributor body was rotated as far as possible into the advance direction. :mad:
The result was that the car ran REALLY hot, even in winter. :mad:
This caused such trouble that they sold the car....and I bought it!:D
I got it cheap. Even the FORD specialist never solved the problem.
My mechanic did....he realised the distributor was out one tooth.
It took him five minutes to correct it...and then it ran beautifully cool, even in summer...and the power increase was AMAZING. :headbang:
Have a real good look ....you might find a similar fault.
Cheers....George 1/8th. :cheers: :cool:
 
George

Thanks for the input.

I don't reckon the distributor is out at all as when I line up the the timing reference point with a 6mm rod in the correct orifice it all lines up with TDC. I've marked this on the camshaft pulley and also marked the advance scale at the correct distances.

The strobe shows her running at a consistent 6 degrees before TDC when idling. This may be a tad retarded but I don't want any pinging happening if I can avoid it. I'm running 98 Octane with Moreys upper cylinder lubricant, and the spark plugs are Bosch Super 4 of the correct listing for the DS.

When I took the Whale on the 50th birthday tour to Canberra, I was disappointed with my mileage figures and the lack of power. It was at Beechworth that Guru Ian Steele in conjunction with Guru David Gries set me right with the timing position.

I was working on the understanding that the timing point determined by the rod in the hole was the firing point, but apparently this is for earlier engines, and on my 1974 beast the rod in the hole is the TDC point. Lacking a strobe at the time I took a punt on a few degrees of advance and Moby fairly leapt up the mountain to Jindabyne, giving me 27 MPG on the way! It was like a whole new car! (Curiously she wasn't everheating at all while running this retarded, so maybe the Cessna Propeller was doing its thing well).

Air flow seems to be unrestricted both sides of the engine. There's nothing there that shouldn't be as far as I can tell. The only change I've made is to add a slightly larger alternator.

Interestingly, I think all of the experimenting was all too much for one item. The temperature gauge is now resolutely sitting on zero so I think it may have stressed out once too often. Then again, maybe she's running so cool now the gauge won't even register? (I think not!) Just what I needed at this stage, as running the ether tube along behind the dash and down to the water pump was something I didn't anticipate having to repeat yet.

Thanks for the thoughts anyway. I just wish it was something that simple!

Cheers, Pottsy.
 
Pottsy

I am beginning to think you have, as you implied, done too much at once. Our D Special never goes over 90C - measured at a point in the block just below the water pump IIRC.

It must be below the thermostat anyway as in winter especially you can tell from the temp gauge when the thermostat opens first time in the day - it's like 85C then plummets to about 40ish then a few minutes later it's back up to a normal 80C. In winter this is also the time when the heater just gets warm, then cold then warm again. :rolleyes:

Then it's toasty warm for the rest of the trip.

On the trip last year to Perth for Cit In, on the run from Esperance to Albany we stuck with two Ds and Mark M's Traction for quite a way. We were the mobile thermometer in the XM and the two ways came into play A LOT. That day ranged from 30 to about 37 according to the XM thermometer. As the temp lowered to about 32 the Ds and the Traction could both lift their speed to around 100km/h. Over 35 and they had to drop back to about 90km/h. Both Ds were running air con. One was a Special same as yours and the other was a 23ie Auto towing a very small campervan.

Our D on runs to Qld and SA has to be driven more by the temp guage (non standard one) than by the speedo if the temp is over about 32. Across the Hay Plain once we varied between 80 and 95C according to the speed. 95km/h would give us about 85C while pushing to 110 would give closer to 95C and you could feel the car starting to labour/drag a bit.

Our D has none of the undertray rubbish on it cause it gives me the shites every time I need to do anything to it, and it is so busted up it is a pain to put back on. I like the look of your chequerplate tray though - looks good and solid, although.... It does look like it sits too close to the engine if you take into account that the brakes have cooling ducts that bolt into the tray and must clear the brakes of course - just my guess from your photo.

I run Nulon coolant in the engine at about 40%. The car does not have an overflow tank although I think it is a three core (?) rad and is non genuine.

The air duct is in pretty reasonable nick too - no holes etc.

Anyway, my :2cents:
 
Hey Potts, have you tried running the car without the checkerplate, as a control test. That's what I'd try....would do no harm.....
Cheers....George.:cheers: :cool:
 
I had a Rover P4 that always boiled over until I put Redline Water Wetter in it (no glycol coolant), which solved the problem until I got the radiator cleaned.
The radiator guy that cleaned it remarked that whatever I was using in the coolant (which was just water and Redline, being at Perth at the time), to keep using it.

The Redline really shunted the heat, but I doubt the Citroen engineers designed the system with that in mind.
 
Pottsy,
I would set your timing a bit higher than 6 degrees with your strobe while running 2000 rpm. Remember measuring at the cam pully is 1/2 the crankshaft measure. If you set a mark with the flywheel pin onto your camshaft pulley, figure a proper 20 to 22 degree advance mark would be about 3/4" to 7/8" measured on the cam pulley, as viewed with a strobe at 2000rpm.
Your engine most likely will like 20 degrees at the crank. I believe a third nose D motor scales to No. 9 in the books.
Is your motor a DV2? a DX2? Check the book for your proper curve.
Yes, you want no pinging upon hard acceleration, but your DS will run best set just below that point when on acceleration.
I make my final settings by ear during road use.

A D motor needs a thermostat in the upper hose. If you like, in summertime, when you don't need cabin heat, you can remove the innard parts of a thermostat, so the coolant flows rather unrestricted. But always leave the brass outer ring part of the thermostat within the upper hose as it prevents boiling coolant, or cavitation of coolant at the water pump.
I use 50 % glycol, 50% distilled water, and a quart/liter bottle of Redline Water Wetter. This works well! (yes peterbro)

You never mentioned if you have a aluminum shroud aft of your radiator, it should be just in advance of the nylon propeller fan? If you don't have an aft shroud here, this is your problem.
Citroen mounted an electric fan here in most of the third nose D's, in front of the nylon fan, the motor is stuck into the propeller nose/hole, and yes the standard thermo switch for the electro fan is mounted a few inches above the bottom of the radiator (right side), just above the drain valve.

Happy Motorin'
Rhodislan
 
Glycol free coolant available at Big W or Woolworths, one of many things that only Woolworths stock.
 
The 12" fan has a surface area of 113 square inches. Two 9" fans have a surface area of 127 cubic inches. The drive motor is a dead zone approx 4" in diameter or 12.6 square inches. So two 9" fans have a usable surface area of 101.8 square inches and the single 12" 100.4 square inches.
Unless the 9" fans have higher rpm capability or a more efficient blade design than your current 12" fan you will gain virtually nothing.

A smaller engine driven fan will generate vortices at the tips as they will not be near enough to the shroud to be disrupted by said shroud. Dependent on the smaller fan's blade design and/or rpm these vortices could render 1" (or more) of the blade tips nonconducive to airflow. Stock fans run close to the shroud for a reason.

As to body mods, vents etc, are they needed? There seems to be few contributors (in hot climates) on this thread that have no cooling issues without said mods? Although the path down past the engine looks tortuous at best, remember any air escaping via this route is also carrying away radiant heat off the exhaust etc along the way.
 
Nope the thread just popped up in the latest posts section.
I wonder if it's still getting hot.🤔
 
Well as the original poster I feel I should make comment here. Moby has had two occasions when he's got hot under the collar since all of the earlier discussions.

The first was on a gentle re-enactment of the 1968 London to Sydney marathon. It was hot, dusty and we went up the back side of Mt Buffalo with the temperature gauge looking to return to zero the hard way. Nothing I could do seemed to alleviate the situation other than stopping a while,. having a relaxing chat and cuppa then continuing. The situation was relatively unresolved all the way back home to Melbourne from Nowra. Problem was solved when I started investigating and found the thermostat had done some gymnastics and turned sideways in the hose. See, that extra clamp IS needed!

Second time was on the first day of the 50th Anniversary Southern Cross Rally. After a couple of autocrosses and a spirited drive up the Whitfield road, once again the temperature was "of concern". Just after starting out from Melbourne I'd picked up my Navigator and we'd noticed some coolant weeping from the driver's side of he engine. In went a container of Leak Stopper, I forget the brand, working on the premise that it should at least slow down any egress of coolant for the duration of the event. At Mansfield after that first day of overheating I drained the coolant intending to check the thermostat. It was then I found the inline filter I'd installed way back when, and cleaned before this event, was clogged! The leak stopper stuff had faithfully stopped the coolant from going through all the holes in the filter! Left the filter element out, replaced the coolant and Moby performed flawlessly from then on.

I've since re-instated the filter and check it regularly. At this date the old bugger is still soldiering on doing the odd drive in the dirty stuff and being immensely enjoyed.

I reckon there must be other threads revived after longer periods, but happy to take the record if not! Curious how it popped up though!

Cheers for now, Pottsy.
 
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