Radiator Drain Point Markings

[Cheshire Steve]

Probably known to everyone, but I am new to this. I was cleaning up the front cross-member of my 1956 Land Rover (Rover Mk 5), after winch mounting holes had been replaced with welded-in tubes. As I removed a flakey black coating I came across these markings that line up with the radiator drain tap.

 

 

First question is whether the marking is DP and the arrow, as it looks like there is a trace of the second letter, but can't make it out, can only see the D for sure.

 

Next question is whether this is an indication anti-freeze was not in general use in the 1950s, as presumably it was the lack of anti-freeze that required vehicles to be drained when not in use. Or maybe it was just a precaustion in case you couldn't get any.

 

The double marking is I think due to there being a marking on the original black chassis, which was then overpainted with a thin coat of bronze green, and the chassis re-marked. The top one is the later one and came off first with some more rubbing down.

 

Any idea when these drain point markings were dropped?

 

This one was struck off in 1958 to Ministry of Supply.

 

Steve

[Ivor Ramsden]

The letters are usually DT, for drain tap, I guess.

[fv1609]

Any idea when these drain point markings were dropped?

 

August 1964

[fv1609]

Officially drain taps should be marked with an arrow DRAIN TAP in 1-in stencil in yellow. In practice this was not always possible & DT was used or even the picture of a stop-cock.

 

This was on a Pig I had, there was a yellow stop-cock at the top the radiator with a series of arrows leading unsurprisingly to the bottom of the radiator.

 

[Cheshire Steve]

Thanks very much. I will replace the mark, but more importantly it reminds me that the drain tap is seized so will have to have that off and give it the once over.

 

I just checked and the military and civilian Land Rovers both had the same drain tap, and not a simple plug, so I guess that was part of life until use of antifreeze became commonplace, drain the engine and radiator overnight if risk of freezing. What a nuisance !

 

Steve

[fv1609]

Steve anti-freeze was common place.

 

In the 1960s it was to be used in all theatres where anti-frost precautions were ordered.

 

Other theatres just water. The drainage was mainly for certain classes of long term storage. Where a "RADIATOR EMPTY" sign was to be displayed. Cooling systems just temporarily filled with water were marked with a red "W" 2-in high superimposed on a white background

[Cheshire Steve]

Aha ! I have found a 1950 Land Rover owners manual and that indicates that Bluecol was available back then, too. So looks like antifreeze was readily available in the UK by at least the late 1940s. Interestingly it says it is important to drain the anitfreeze mixture when the winter is over and flush several times with 'very hot soda water in order to removal all traces'. If this is not done it says it will result in boiling over problems after a couple of seasons.

 

So the drain tap would have had a lot more use than it does these days.

[fv1609]

In relation to 1964, vehicles in storage, dependant on their type of storage, anti-freeze was changed only 3 or 4 yearly. At the time it was AL3 (Ethylene glycol) this later changed to AL39 which was the same but included inhibitors, sodium sebacate & benzotriazole.

 

August 1964

 

Perhaps I should substantiate this with references. WO Code No.14022 Regulations for Army Ordnance Services, Volume I, Pamphlet 6 - Supplement, Maintenance in RAOC Vehicle Depots etc 1963.

 

In Amendment 1 Jan 1964 Section 44 it quotes markings (a) to (n) that are likely to be obliterated during painting & need to be re-instated. (i) refers to DRAIN TAP.

 

In Amendment 2 Aug 1964 it covers markings (a) to (m) the reference DRAIN TAP is now removed, everything subsequent to that moves up one.

[wally dugan]

l think you will find that anti-freeze came into general use in the 1920s

[Ivor Ramsden]

l think you will find that anti-freeze came into general use in the 1920s

 

That might be correct but judging by the instructions in most early wartime WD drivers' manuals anti-freeze wasn't always in use by the army because drivers were instructed to drain their radiators when their vehicle was out of use in freezing conditions.

 

Vehicles with anti-freeze installed were specially marked to that effect in an attempt to stop drivers draining them but I can't recall seeing any pictures showing such markings before about 1943. (Cue a flurry of pre-1943 photos, hopefully!)

 

Steve, be very careful freeing off your Series 1 tap. The brass can be very brittle and it could break. Also, once it's freed off, you might find that it leaks because the spring that keeps the twisty bit (sorry about the technical jargon) tightly in place in the tap body might have rusted away. It's not a big job to repair it but I've found that it's difficult to find a replacement spring that won't rust away in a short time.

[wally dugan]

IVOR in post 7 steve seems to be saying that he found reference to the use of anti-freeze in 1950 my point was that anti-freeze was about long before then not that military vehicles where all using it l remember in the early 1960s local farmers draining there petrol paraffin tractors radiators on winter nights and not filling them with a anti-freeze mix just straight

tap water

[Cheshire Steve]

Thanks, Ivor, for the advice on freeing-off the tap - and the potential problems.

 

Steve