Radiator expansion tank: Alert!

[Wasa57]

2000 td5 sls auto ace

While fitting a new coolant expansion tank cap a few days ago, noticed
a stream of coolant out of the overflow pipe as the engine warmed. Hmmm...hadn't noticed that before...
Later, as the engine cooled, could hear a popping sound. Next days after short drive, a check revealed coolant level had dropped by about 1cm. Not good.

The culprit was a pin hole in the neck of the filling chamber, directly where the radiator output pipe enters the inlet chamber, on the inside.
This area happens to coincide with the overflow hole / ring in the filler cap, so the result was instead of flowing into the expansion chamber, the coolant was directed out through the cap and the overflow pipe.

Obviously the usual syphoning effect of cooling fluid in the radiator which draws coolant back from the reservoir was negated by the pinhole (hence the popping sound!)
So, a pinhole in the filler neck left undiscovered may have led to an overheated head, a breakdown (potentially out the back of beyond) and many $$$ in repairs. Have just ordered a new expansion chamber, and thinking seriously about an "engine saver."

[gavinwibrow]

2000 td5 sls auto ace

While fitting a new coolant expansion tank cap a few days ago, noticed
a stream of coolant out of the overflow pipe as the engine warmed. Hmmm...hadn't noticed that before...
Later, as the engine cooled, could hear a popping sound. Next days after short drive, a check revealed coolant level had dropped by about 1cm. Not good.

The culprit was a pin hole in the neck of the filling chamber, directly where the radiator output pipe enters the inlet chamber, on the inside.
This area happens to coincide with the overflow hole / ring in the filler cap, so the result was instead of flowing into the expansion chamber, the coolant was directed out through the cap and the overflow pipe.

Obviously the usual syphoning effect of cooling fluid in the radiator which draws coolant back from the reservoir was negated by the pinhole (hence the popping sound!)
So, a pinhole in the filler neck left undiscovered may have led to an overheated head, a breakdown (potentially out the back of beyond) and many $$$ in repairs. Have just ordered a new expansion chamber, and thinking seriously about an "engine saver."
Thanks for info. If nothing else - don't "think seriously" - just do it. It's cheap insurance and you have a number of options/prices.

[infrno]

Scuse my ignorance in this one... Having just forked out enough cash to get my disco lifted, new rims n tyres on it and some other stuff getting a changeover motor put in after the old one overheating I'm very interested in what you guys are talking about with the engine saver....

[gavinwibrow]

There are a number of threads in this forum.

Dave sells one which regularly appears at the top of the page,- go to the "shop" above or see
Dave's Interesting Things (http://www.davesitshop.com/davesitshop/index.php?_a=viewCat&catId=30)

There is also the South African Madman EMS which incorprates a temp gauge and a low coolant alarm - I saw this morning that TheEntertainer an AULRO member on this forum is a seller.

Se also ENGINE WATCHDOG TM2, Engine Temperature Sensor and Low Coolant Alarm (http://enginewatchdog.com/tm4.html)

There are others which I'm sure members can add to

Happy hunting

[infrno]

Thanks - I was looking into getting an Ultragauge which does a whole lot of things, but I don't think has the low water alarm specifically like Dave's unit.. more to think about!!

[p38arover]

The culprit was a pin hole in the neck of the filling chamber, directly where the radiator output pipe enters the inlet chamber, on the inside.
This area happens to coincide with the overflow hole / ring in the filler cap,

That's not a fault. I'm pretty sure that's part of the reservoir design if it is the same tank as use on the P38A (I think it is). My previous tank had it and so does my present tank. I have another spare in the garage, I'll check it.

Hmm, can't find it.

P.S. I used to live in Carnarvon in 1971-72. I worked as a tech officer at the OTC Satellite Earth Station and my wife worked down the road at the NASA Tracking Station doing solar photography.

[Wasa57]

That's not a fault. I'm pretty sure that's part of the reservoir design if it is the same tank as use on the P38A (I think it is). My previous tank had it and so does my present tank. I have another spare in the garage, I'll check it.

Hmm, can't find it.

P.S. I used to live in Carnarvon in 1971-72. I worked as a tech officer at the OTC Satellite Earth Station and my wife worked down the road at the NASA Tracking Station doing solar photography.


Thanks, it's back to the drawing board for me if the hole is normal. The level has only been dropping since I fitted a new cap a few days ago...the
new cap is identical, and I only bought it because the O-rings on the old one were flattened.

The Big Dish, Sugar Scoop, and a few other bits are preserved up on Brown's Range, with restorative work ongoing towards a museum etc.

[gregausit]

FWIW I just travelled 4500 km towing 2 tonne, on the last 100 ks just near home, I stopped and was idling for about 15 mins, anyways, I noticed a small amount of fluid under the car, had no AC on so I know it was from the overflow most likely.

Anyway, whilst waiting on someone, I openened th e hood & decided to look at and top up the resivoir, no drama, did not take much fluid at all.

Got back in and drove about 500m, stopped for a min, then went to continue, I noticed the guage went above its usual half way to about 3/4, pulled off the road and shut down straight away as is a TD5.

On looking again underneath, heaps of water....uh oh I am thinking, but at least I saw it before overheating.

Got out the water, topped up again once idling then proceded to a station as needed fuel as well, I looked ack when at the station and water everywhere trailing behind, but could not see where it was coming from when idle.

let cool down, topped up again, moved 20m and again water.

Still no sign of where it was coming from, but could see most was around resivoir side, when topping up this time, as doing up the cap, I saw it start pouring out the overflow tube...mmm

I was a bit stuck, needed to get home, no evidence of major breakage or where this water was really coming from, decided to fill as much as possible & this time I tightened cap as much as possible, and headed out watching the temp indicators.

was straight onto a very steep hill that climbs a mountain, anyways, if it was going to loose all the water again, it would happen there, to my surprise, climbed hill and made it all teh way home and a week later still no real hard evidence of what went on.

All I can surmise is that the overflow tank and cap were hot from towing then idling, once I opened the cap I must never have secured it properly due to both materials being hot and that causing me to think I had tightened enough.

Maybe this is what people are experiencing ? or maybe the cap has a problem ?

Came here to look to see if it was common on D2 TD5's