Headlamp Issues

I’m converting my open headlamp 67 to a closed headlamp '67. I ordered the buckets with the flat back. Problem is that the plug that goes on the back of the 7" headlamp bulb hits the flattened back of the bucket and prevents the bulb from fitting into the retainer.

How did the open headlamp cars deal with this? Is there a different kind of plug?

You’ll also find the open headlamp seating rim of the sealed beam orients with the flat backed buckets 180 degrees out. Even if you could use the sealed beams they’d be upside down. You will need to source the S1 galvanised seating rims, chromed headlamp inner rims as well as lamps that will fit them. I happen to be in the midst of doing the conversion on my Series 1½ and have ordered the requisite parts from SNG Barratt. Haven’t picked them up yet so can’t vouch for the fit, but do know the parts from the later open arrangement aren’t compatible.

Is it supposed to be flat backs for 67 (closed obviously)? My 64 has slant backs.

How deep are your headlamps? Not all 7" glass fits in using the standard 3 pin Molex socket. You might need to source angled sockets (if that exists) or thinner lamps.

Slant backs would describe them better but we’re talking about the same thing - there’s a portion of the bucket that’s flattened to clear the tire. In any event, the round backed bucket of the open headlamp arrangement mates with its seating rim such that the aim adjusters are at 9 o’clock and 12 o’clock while the flat (slant) backed bucket of the closed headlamp arrangement mates with its (different) sealing rim with the adjusters at 3 o’clock and 6 o’clock (or something like that, 180 degrees out). The three slots in the open headlight seating rim mate with three corresponding tabs on the sealed beam so will mount to the closed headlight bucket only one way, ie upside down. I suppose you could modify the flat backed bucket to take the later seating rim but as you say you still need to find lamps that fit. The halogens I installed in my Series 1½ are too deep, their three prong connections foul the flattened back of the bucket.

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I put Cibie Z-beams in mine and they fit fine with my buckets and the standard plug. Hellas work also, as did PL700s when I had those installed.

Nick, Sorry, I’m not following. I do not see how turning the headlamp assembly 180 will make a difference. Are you saying that the seating rim is different in some way that makes it deeper?

Erica, Are you saying that Cibie Z-beams are not as deep as the standard Lucas sealed beam? I’ve looked at them online and do not recognize a substantial difference.


I can only say for certain that mine fit fine in slant back buckets. I think it is the case that the aluminum basket that the lamp sits inside can feasibly be varying distances from the rear of the bucket because the basket floats on adjustable srews. So the screws may be screwed in a little bit or a lot of bit, as long as the ratio of horizontal to vertical attitude is correct. So that’s another variable to consider.

Turning the assembly 180 degrees will make no difference, You need diffterent parts to make it work,

Here’s a pic of my closed head lite may help the discussion

Correct, the pigtail must face up when assembled. The slanted angle is so the tire won’t hit it on a deep suspension compression.

The measurement from the reflector edge to the tips of the bulb connectors must be no more than 3" to fit in the S1 slant buckets. The only ones I can get to fit are the Wipac
Here is a comparison of the 3" high Wipac with the 3.75" Cibie:

A workaround is to dump the OE connector and solder or crimp spade connectors to the wires and bend the connectors over to gain clearance.

Herb, the pic posted by Jim shows where the screws for adjusting headlamp aim are located, viewed from the front they’re at six o’clock and 3 o’clock.

This is a pic showing where the adjustment screws are located for the open headlamp arrangement, at twelve o’clock and nine o’clock.

The sealed beam is keyed to its seating rim in three places - it mounts only one way in order to position high/low beams correctly

So, to mount the open headlamp with its seating rim to the flat backed bucket you’d have to rotate it 180 degrees to align the adjustment screws.

Alternatively, you could try to modify the flat backed bucket to relocate the two adjusters, but better to source the correct parts.


I did not realize there was such a difference in bulb depth. The Lucas sealed beams I have are about 3.5 inches from the tips of the spades to the front of where the reflector meets the glass. Are you saying that all cars with slant back buckets have this issue?

What year is your car?



The slant back buckets I have give the option of putting the adjusters at 3, 6, 9 or 12. But I do not see how that makes a difference. Please explain.


Hi Herb

I have a '62 FHC and a '63 OTS. All S1 cars have this problem as you only have a tad over 3" distance from reflector edge to the bucket slant. The Factory fitted bulb Lucas reflectors except for the US where sealed beam were mandated so GE units were installed by the Distributor.

Only reflectors I can find that will fit are certain Wipac and Lucas ones. If you want Cibie or Lucas sealed beam you need to jerry rig the connectors with right angle spades without the plug body and also bend the tabs upwards to maintain clearance. Obviously insulation is a must.

  1. Remove connectors from block
  2. Heat shrink insulation
  3. Bend the connector ends 90 degrees
  4. Trim H4 bulb terminal length by about 1mm
  5. Bend the headlamp seating ring tabs x3 down so that the chrome trim ring sits snugly without moving

You could try/add this connector set or just use the 90 degree spades before assembly.

Cibie Z beams fit fine in my 64 using standard 3 terminal ceramic sockets. I have some spare ones somewhere and will try and measure them.

Where does one find the 90 degree connector? Could use a pair for my Morgan 3W.

That’s interesting. The buckets I have feature only the 3 and 6 o’clock adjusters, which correspond to the holes in the headlamp diaphragm.

If you have the option, then you can reuse the open headlamp hardware. The reason you can’t mount the sealed beams upside down is it would mess up the high/low beams - think about it.

Cibie Z beams are no longer available I believe. The Z refers to the beam pattern incidentally. There are repros available but not sure if they will fit, look a bit too deep to me.