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Land Rover Series 3 109 - Ex Ministry RACAL Jammer & DF Control Unit


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7 hours ago, fv1609 said:

Looks like the ignition coil has been fitted incorrectly & it is running off a +ve HT spark rather than a -ve spark  :  (

This can identified by one of the two drain holes being visible from above. A drain hole is for draining moisture & needs to be on the underside of the coil with one hole facing downwards in order to drain!

The 5C10 coil is supplied with a rubber bung in each drain hole. On fitting the coil, one bung should be removed from the most dependant drain hole. With the coil positioned correctly the short screened cable from the ignition filter box can comfortably reach the SW terminal on the coil.

If the coil has been incorrectly fitted with a drain hole visible on the top, it means that the cable from the filter box cannot reach the SW terminal so instead it gets fitted to the CB terminal leaving the screened cable to the distributor getting fitted to the SW terminal.

Thus the HT instead of producing a negative spark at the sparking plugs has a positive spark. A spark jumps more readily from a relatively hot centre electrode in the plug than jump from colder electrode at the side of the plug. This anomaly means poorer engine performance.

When this anomaly is pointed out, some owners find it hard to accept & wish to leave it as it is on the basis they they feel it is running ok & besides they had the vehicle straight out of service so it must be correct.

Other owners have been bugged with poor engine performance shown by a lack of power & a propensity for the engine to conk out at certain times. On changing the coil to the correct orientation there has been improved running & reliability.

Unfortunately most variants of these coils were issued as spares with the clamp 180 degrees out of phase if the coil is to be fitted on top of the engine like this. The temptation is to fit a replacement coil directly in place without any regard for the SW & CB markings stamped on the coil. It shows a poor understanding of the workings of the ignition system if the purpose of markings are not adhered to. This is a problem of in-service mechanics as well as private owners.

Another consequence is that with time, spark erosion will mean that the rotor arm wears down (rather than gain metal) but at a rate four times faster than the erosion that the pillars inside the cap would had it been correctly fitted.

Another very obvious consequence is that the terminals within coil cover will become partially submerged giving rise to electrical breakdown & corrosion.

There is nothing new about the requirements of fitting these screened coils, there was an EMER issued in 1958 highlighting the need for correct fitting.

823339967_83KB31coila.jpg.69c65918d0279617310466d7dfd28899.jpg  

   702780423_DSC04917(Small).JPG.26903f38b4dbf88ed6140f7adef310f3.JPG

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11 minutes ago, fv1609 said:

This can identified by one of the two drain holes being visible from above. A drain hole is for draining moisture & needs to be on the underside of the coil with one hole facing downwards in order to drain!

The 5C10 coil is supplied with a rubber bung in each drain hole. On fitting the coil, one bung should be removed from the most dependant drain hole. With the coil positioned correctly the short screened cable from the ignition filter box can comfortably reach the SW terminal on the coil.

If the coil has been incorrectly fitted with a drain hole visible on the top, it means that the cable from the filter box cannot reach the SW terminal so instead it gets fitted to the CB terminal leaving the screened cable to the distributor getting fitted to the SW terminal.

Thus the HT instead of producing a negative spark at the sparking plugs has a positive spark. A spark jumps more readily from a relatively hot centre electrode in the plug than jump from colder electrode at the side of the plug. This anomaly means poorer engine performance.

When this anomaly is pointed out, some owners find it hard to accept & wish to leave it as it is on the basis they they feel it is running ok & besides they had the vehicle straight out of service so it must be correct.

Other owners have been bugged with poor engine performance shown by a lack of power & a propensity for the engine to conk out at certain times. On changing the coil to the correct orientation there has been improved running & reliability.

Unfortunately most variants of these coils were issued as spares with the clamp 180 degrees out of phase if the coil is to be fitted on top of the engine like this. The temptation is to fit a replacement coil directly in place without any regard for the SW & CB markings stamped on the coil. It shows a poor understanding of the workings of the ignition system if the purpose of markings are not adhered to. This is a problem of in-service mechanics as well as private owners.

Another consequence is that with time, spark erosion will mean that the rotor arm wears down (rather than gain metal) but at a rate four times faster than the erosion that the pillars inside the cap would had it been correctly fitted.

Another very obvious consequence is that the terminals within coil cover will become partially submerged giving rise to electrical breakdown & corrosion.

There is nothing new about the requirements of fitting these screened coils, there was an EMER issued in 1958 highlighting the need for correct fitting.

 

  

Good call Clive,

I experienced a coil incorrectly wired once, when the engine stopped and I subsequently found a flux like build up on the inside of the distributor cap on the brass "terminals" for the plug leads, scrapped it off, reconnected the coil correctly and good as gold after that. I did change the rotor arm as well as these deposits would have been from it.

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Richard yes one owner described what he found inside the distributor cap was a bit like burnt matches. Once cleaned & the coil correctly fitted it all ran very well for the first time since he had it direct from auction.

It is not unknown for owners of a vehicle on display to fly off the handle if anyone questions anything about the vehicle, which is a great shame as it does nothing to enhance the hobby. But sadly I have found a reluctance to accept the prima facie evidence that the connections are wrong and that drain holes can't drain if they point upwards!

Sometimes there is an acceptance, but it runs ok so why should they change it just because I say it's wrong?  :  (

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Winterization complete ,  however note the  three  qty.  Lift-the-Dot above the plastic radiator grille , this indicates it had the later design radiator blind for cold-climate - easily restored.  The headlamps may have had small canvas flap covers.    Hardtop  connection/panel -  240v  ?   side one is probably for "Slave-Start"  /  heli-start  ?  ,   SS is normally in passenger footwell.   

I once had a perimeter walk around one of these approx.  1995  at Land Rover franchise dealership  North Eastern Motors  , Lemington (original premises) .   A mechanic told me that under regular servicing by franchise dealers ,  few of them and stored at TA depot garages around UK.  He also told me the side  & back door were always kept locked ,  ISTR the back door had a extra hasp and padlock.

Must have been lots more electronic equipment in the back originally.

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Richard, I am after Landie, but to use for carrying stuff, really and it would be a waste to strip out what is left of the gear.....and I don't fancy having yet more stuff to store!  Hope someone buys it to put back as was, though.

On drain holes in electronic components, I was always under the impression that the little hole in my magneto points cover on my Matchless WD3L (and on most WW2 WD bikes) was a drain hole and should face downward.  Not so; it is to allow corrosive gases from the arcing to dissipate, and it should face UP!  (I am NOT at all suggesting Clive is wrong, rather its easy to make erroneous assumptions!).

Edited by matchlesswdg3
correction
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If only he'd move his foot!  But... it's close.  640SignalTroop_norway21.jpg

 

These vehicles were very uncommon - a handful at most which, as can be seen from the spiel, were specially equipped by Racal and used by 640 Signal Troop for the out-of-area and NATO flanks role carried out in BAOR by 14 Signal Regiment (EW) - so had a similar role to some of their larger 1 tonne Land Rovers.  This photo - credit to the owner via the internet - shows the same or similar vehicle with 640 on exercise in Norway - hence the winterisation.  As I said, they were very rare and wouldn't have been held in TA centres.  I suspect what Tony is referring to are the MOULD insertion vehicles which were used by TA R Signals units to support the MOULD VHF emergency network which entered service in the early 80s, or, if that is too late, to their predecessors.  The MERLIN record shows that this vehicle in fact went on to serve with 14, probably after that regiment returned  from BAOR to new barracks in UK.  Quite what the connection with the Dutch Embassy is, though, I have no idea, unless it was involved in some demonstration for them!

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Just pondering , this is not important - the  B Card , normally the vehicle hardware nomenclature plate is left alone but the Asset Code gets a line through and a winterized code.

Also,   has the seller correctly identified it as a RACAL correctly ?     Some of the MOULD 'insertion'   would probably be winterized for very good reason(s).     I think the year was 1979  ,  I just got clear during a heavy snow-storm -  the last in a Que to drive out (1250cc Chevette),  a couple behind were not so lucky - their bodies were found under snow 6 weeks later - this was exactly at a MOULD camping site in regular use for practice.

Visually they were almost the same - roof rack etc.,  photograph of MOULD in civvy livery - seems to show Jerry can holders on front bumper - a clue , they were campers.    Scroll down for pic ,,    http://www.ringbell.co.uk/ukwmo/Page251.htm

You will see  PYE equipment installed inside a MOULD.      This  109" for sale , I accept the B Card has the clue  Racal-SES  (whatever SES means)  , but Racal could have been contracted to install PYE radio MOULD   ?       PYE tended to be more commercial communications,  Racal were much involved with military radio Land Rovers.

 

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That was certainly an interesting link Tony offered to the MOULD site, but, as Richard says, the vehicle above has no connection.  The MOULD vehicles were, according to Fletcher/Taylor 109" CLs in the ERM batch 03HJ71 to 04HJ03.  22 were insertion vehicles and 11 repair vehicles.  They were also supported by CL GS stores vehicles.  He is correct in that they were fitted with jerrican holders on the front and, in the photo he shows of them in civilian garb, the holders are all visible.  As are the civilian style chrome aerials on the front wings and the diagnostic roofrack which was of very substantial construction.  I doubt they would have been winterised - they had no overseas deployable role (hence their being CLs) and vehicles were only converted where there was a likelihood of their being deployed to the NATO flanks - 3 Cdo Bde, the RAF Harrier force, AMF(L) and so on.

 

No, I think the vendor is on the right lines - he has an FFR with the correct details - even the lifting rings on the front bumper appear in the "in-service" photograph and the roof rack is of a regular pattern.  The ERM is right, the fact that it's an FFR etc etc.

 

As for what was inside, well it would have been equipment sourced from a number of different places and they were very heavily laden.  Here are a couple more photos of the troop on exercise in Norway - again credit to the copyright owner on the internet.640SignalTroop_norway1.jpg640norway3.jpg

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