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Sprint Headlight Flasher Relay Serial Number?

PostPosted: Wed Aug 15, 2012 11:42 pm
by l10tus
Can anyone tell me the O.E. Sprint Headlight Lucas Flasher Relay, serial number please?

Is an alternative available that still does the job ?

Also, oes this circuit use a 'standard' flasher can ?

Thanks,

Phil.

Sometimes my Lotus makes me cry.
'72 DHC UK Sprint

Re: Sprint Headlight Flasher Relay Serial Number?

PostPosted: Fri Aug 17, 2012 9:19 pm
by l10tus
Can anyone tell me if there should be load via the headlights operating the flasher unit, or is it just flashed by the 12volts from the light switch ?

I've tried for hours and hours to get the lights to flash to no avail !

Some 'experts' sy I need a special 6 RA relay - some say I don't

Some say I need a special flasher can, some say not !

Still can't get them to flash !

I've recently bought a new 6RA relay and 'special' flasher can unit, but the dam things still won't flash.

I'm pretty sure the wiring is correct, because, when I manually lift the L/H pod the H/lights come on.

And coversly, when I disconnect the flasher connections, they don't come on - (so the earth path is good).

Can anyone confirm that the H/lights continue to flash, without the engine running ? - or is this needed to be running in order to provide enough power to operate the flasher unit.

Is any of the H/light power needed to operate the flasher, not just the 12vflasher / microswitch/ earth, circuit alone?

Need some answers please from someone who has come thru the 'pain barrier' and sorted the operation of the system out??

UK Sprint wiring.

Anyone willing to help me sort this once and for all?

I'm loosing the will to live with this!

Thanks,

Phil.

Sometimes my Lotus makes me cry.

'72 DHC Sprint.

Re: Sprint Headlight Flasher Relay Serial Number?

PostPosted: Sat Aug 18, 2012 4:50 am
by YellowS4DHC
Phil

don't have any answers for you but I share your pain. I haven't been able to get mine to work either.

When I connect up a 6 RA relay without the flasher in the system, it will make the lights go on when the light pods are raised (light sw still in off position). Good enough, but when I add the two-prong flasher unit (new from Paul Matty), the lights don't flash.

I got frustrated and started putting in time on my wife's car. :cry:

Rick

'69 Elan S4 DHC
'57 T1 Speedster
'67 S800 Coupe

Re: Sprint Headlight Flasher Relay Serial Number?

PostPosted: Sat Aug 18, 2012 5:38 am
by oldelanman
Hi Phil,
Well I could be very wrong here but my understanding is that the only thing "special" about the original relay is that it has only three external connections, W1 and C1 being connnected together internally. I don't think this type is available now but a 6RA type make/break with four connections will do just as well - simply connect W1 and C1 externally. As for the original flasher unit I suspect it would have been "special" in that it was designed to give the required flash rate in a circuit where the only load is the relay winding, not two 21W indicator bulbs as with a standard unit. My system works fine with a Lucas 9FL hazard flasher unit which I happened to have lying around and flashes around once/sec, I don't know what the flash rate was with the original flasher unit - perhaps someone will be able to tell us ??
This is how mine is wired........
Headlamp flasher circuit 002.jpg and

Re: Sprint Headlight Flasher Relay Serial Number?

PostPosted: Sat Aug 18, 2012 8:12 am
by 45bvtc
I believe its a: Lucas FL5 with the part number: 35020A

I have one in front of me that you can have (plus several other original type Lucas headlamp relays remaining from 40-years of Elan ownership) if you want to collect. I'll PM you with my details.

Re: Sprint Headlight Flasher Relay Serial Number?

PostPosted: Sat Aug 18, 2012 1:19 pm
by l10tus
Roger, John, rick, thanks for the replies, all valuable!

Seems the wiring diagram is correct and exactly the same as yours Rick, but I've since been informed that although I've purchased a 'special' flasher can from SM, I still require the original style and specification of 6RA flasher relay, to enable it to operate from the relay's coil resistance (only).

Unfortunately, This original relay is no longer available.

However, Dave has suggested he may be able to source or remanufacture a suitable replacement in the near future, as he has done in the past, with the flasher units.

I tHink you will see his post on this topic later.

Well I for one will eagerly buy some of these from Dave, as soon as!

God speed Dave!

I did read the discussion in the Headlamp thread, where Brian and Alex Black seemed to be experimenting with an alternative wiring connection layout, in connecting the flasher into the Yellow/ Blue supply feed cable from the Headlamp switch, Infront of the 6RA relay, thus ensuring the shared /piggyback feed to the Headlamps was also drawing on the flasher unit, and ensuring the flasher operated with this load on it as well as the single, relay coil option.

Alex / Brian can you confirm if this was successful ?

Regards,

Philip.

Sometimes my Lotus makes me cry.

Re: Sprint Headlight Flasher Relay Serial Number?

PostPosted: Sat Aug 18, 2012 4:00 pm
by types26/36
l10tus wrote:Some 'experts' sy I need a special 6 RA relay - some say I don't
Some say I need a special flasher can, some say not !
Can anyone confirm that the H/lights continue to flash, without the engine running ? - or is this needed to be running in order to provide enough power to operate the flasher unit.


I don't think the relays are anything special, even the flasher unit is just a two pin unit.
The picture is of my Sprint but from memory I fitted a universal flasher unit to my S2 although both cars flash at a different rate.
The headlights flash even if the engine is not running.....don't even need the ignition on but the headlight switch must be in the ?OFF? or ?Side Light? position.
It will not flash if the headlight switch is in the ?Headlight? position.

Re: Sprint Headlight Flasher Relay Serial Number?

PostPosted: Sat Aug 18, 2012 4:06 pm
by types26/36
Just found this thread where I give a name/number of the flasher unit I used on my S2.
elan-f14/move-over-flashing-headlights-t12263.html

Re: Sprint Headlight Flasher Relay Serial Number?

PostPosted: Sun Aug 19, 2012 3:34 am
by prloz
Hi Guys,
It's simple really. You must use a 6RA relay or similar with a 4 ohm (approx.) coil resistance.
Most modern relays have a coil resistance of a few hundred ohms, (far too high for this application....... not enough current flow through the flasher)
Regards,
Peter.

Re: Sprint Headlight Flasher Relay Serial Number?

PostPosted: Sun Aug 19, 2012 11:40 am
by l10tus
Prioz,
thanks for the reply.

I agree, the really simple bit is working out the relay should have approx. 4 ohms resistance, but the really, really, hard bit - is finding someone who can supply one!

Do you have any idea's ?

Regards,

Philip.

'72 ?lan DHC

Sometimes my Lotus makes me cry.

Re: Sprint Headlight Flasher Relay Serial Number?

PostPosted: Sun Aug 19, 2012 1:23 pm
by prloz
Hi Philip,
Try a 4 ohm wire-wound resistor (say 25 - 50 watt) across the coil of your relay.
Regards,
Peter.

Re: Sprint Headlight Flasher Relay Serial Number?

PostPosted: Mon Aug 20, 2012 12:18 pm
by DaveAlmey
Hi All,

As promised my response.

The flasher units I had made are identical to the origional two pole units as supplied by Lotus. They will work ok, provided they are use in conjunction with the origional style headlamp flasher relay which, when we checked one earlier today from my S4 project has a resistance of around 8 ohms. It would appear these flasher relays are no nonger available, I have been trying to fins an OEM part number without success.

Most 12vdc relays have a resistance of above 260 ohms and therefore do not pull enough current throught the flasher relay to enable the mehanical relay to work.

One solution is to fit a 10 ohm 20w resistor in parralell with the 6RA relay coil.

Re: Sprint Headlight Flasher Relay Serial Number?

PostPosted: Tue Aug 21, 2012 4:51 pm
by l10tus
Dave,

Thanks for the info.

Also, thought I had better let you know that I've managed to fix the flashing headlights without the special relay!

Alex Black said to try wiring your special flasher (obtained from Sue Miller) in the wire circuit from the Standard 6RA flasher relay to the headlights - in the Blue / White wire, not in the earth path circuit after the relay, before the pod microswitch and eart, etc.

I know this is not as per the wiring diagram, but it works perfectly.

Just can't believe that the 'special relay ' is not required.

This will make lots of owners very happy, I'm sure ?

Must be a very lucky coincedence that your flasher can works with the standard 55Watt headlamps - spot -on.

How's that for teamplay?

Best regards,

Philip.

Sometimes my Lotus makes me cry.

Re: Sprint Headlight Flasher Relay Serial Number?

PostPosted: Fri Aug 24, 2012 8:00 pm
by YellowS4DHC
Phillip,

Thanks very much for passing on Alex Black's suggestion regarding wiring the flasher unit in the WU line. I tried it this morning and it, as you said, works perfectly. Woo-Hoo!

Alex Black - a tip of the hat to you sir.

A year and a half ago I figured out I needed to short the 6RA relay (as shown in Roger's diagram), but my Lucas FL5 flasher would not work in the original position in the line going to grd via the pod microswitch; I suppose it would have worked if I had a 9FL unit like Roger. Moving my FL5 flasher into the WU line was all that it took.

My wiring is represented in the attached diagram. Dashed lines represent wires that need to be added.

regards
Rick

'69 Elan S4 DHC
'57 T1 Speedster
'67 S800 Coupe

Re: Sprint Headlight Flasher Relay Serial Number?

PostPosted: Sat Aug 25, 2012 9:27 am
by l10tus
Rick,

Thanks for posting the drawing, that's spot - on!

Works well dosen't it ?

What I can't work out, is why nobody actually tried this before !!

Seems so obvious now - (as is often the case!).

As the indicator flasher is wired in exactly the same way.

Just find it incredibly lucky that Daves' (supplied by Sue Miller) flasher can is so suitable ?

For me, I suppose the line is drawn under this one now.

Best regards,

Phil.

Sometimes my Lotus makes me cry.

'72 Sprint DHC.