Adjusting Spot Lamps

Something sketchy going on

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Mongrel505558
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Adjusting Spot Lamps

#1

Post by Mongrel505558 »

The other day my right spot lamp and turn signal lamp flopped loose on the mounting bracket. l I removed the turn signal housing to access the 9/16 nut on the spot lamp housing stem. I will fabricate a slotted 9/16" deep socket to go around the spot lamp wire, but for now I cut the wire at the ring terminal and pulled it down through the stem. Took apart to verify the parts, but I'm not sure I installed the lamps correctly previously. Page 106 of the '58 to '68 Parts Catalog shows the 3/8-16 lock nut (item #6), a clamp block (item #31) and a swivel washer (item #27). I have it assembled with the washer bearing on the top inside surface of the turn signal mounting bracket (item #8) followed by the clamp block with the domed side facing up, and then the locknut. On the top side of the mounting bracket that attaches to the nacelle I have a larger domed swivel block (item #32) that the bottom of the spotlight housing should swivel on. Basically it looks like the order in the book.

Problem is when I tighten the locknut the whole assembly tilts forward/downward no matter what angle I start with and how tightly I try to hold it. It seems that as I tighten the nut the stem wants to self-correct it's alignment so it's square with the top inside surface of the turn signal bracket.

What is the function of the clamp block (#31) and what should it's position and orientation be in relation to the other components? The washer that was in there for what the book calls the swivel washer (#27) is just a 3/8" flat washer in my case. Is this correct or should it have a concave surface on the face that the convex clamp block bears against? I'm just not seeing how these two parts work together to allow "swiveling". Also, I googled the part number for the clamp block and the pictures I see of it it's domed for its full length, where the one I have has a domed "shoulder" and then a flat top. I suspect that's part of the problem.

I'm not having this problem with the left assembly. I suppose I could take that side apart and confirm how it's assembled, but I feel like the answer is staring me in the face and I'm just not seeing it.
RooDog
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Re: Adjusting Spot Lamps

#2

Post by RooDog »

Jim....
Check your email...
nifty
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Re: Adjusting Spot Lamps

#3

Post by nifty »

spotlamp hardware.JPG
From a real Guide spotlamp, off a 65 Pan
Edited to synch with Jim's cad drawing
From right,
68720-62 CLAMP BLOCK (2) 62-84; .391" ID x .687" OD x .165" high (flat underneath) . Small conical/radiused spacer/doohickey has plain 3/8" clearance bore for stud of spotlamp. Appears to go on underside of bracket/bar clamp with cone upwards into hole of brkt. Allows nut to lock 68720-62 CLAMP BLOCK into bracket at a slight angle. i.e. cone bites hole in bracket.

68721-62 SWIVEL BLOCK (2) 62-84; .614" small ID x .775" big ID x 1.375" OD x .338" high (flat underneath). Big conical/radiused spacer/doohickey has tapered bore, which allows stud to tilt; the large conical/radiused face of swivel block seats and swivels against depression in spotlamp body. i.e. this swivel block appears to go on lamp stud first, with its flat side visible. The stud can then pass through bracket at an angle and clamp block locks it at chosen lamp aimed angle. Only a few degrees tilt possible.

68693-38 SWIVEL WASHER (2) 41-84 Normal 3/8" flat washer .404" ID x .869 OD x .110" thick, goes inside pedestal of signal lamp.

7778 LOCKNUT, (2) 3/8·16 x 7/16 high x 9/16hex, (2) normal 3/8" UNC Nyloc nut, goes inside pedestal of signal lamp.

Well that's how I currently think it should work, someone else might know for sure, Identification in parts books is poor, service manuals say zip.

Nifty
spot mount.jpg
68720-62 clamp block.jpg
swivel block assy.jpg
68721-62 Swivel Block.jpg
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Last edited by nifty on Thu Sep 15, 2022 11:09 pm, edited 2 times in total.
Mongrel505558
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Re: Adjusting Spot Lamps

#4

Post by Mongrel505558 »

nifty wrote: Thu Sep 15, 2022 6:37 am spotlamp hardware.JPGFrom a real -62 Guide spotlamp, off a 65 Pan

From right,
68720-62 CLAMP BLOCK (2) 62-84; .391" ID x .687" OD x .165" high (flat underneath) . Small conical/radiused spacer/doohickey has plain 3/8" clearance bore for stud of spotlamp. Appears to go on underside of bracket/bar clamp with cone upwards into hole of brkt. Allows washer & nut to lock 68720-62 CLAMP BLOCK into bracket at a slight angle. i.e. cone bites bracket, washer never touches bracket (except one edge at max tilt).

68721-62 SWIVEL BLOCK (2) 62-84; .614" small ID x .775" big ID x 1.375" OD x .338" high (flat underneath). Big conical/radiused spacer/doohickey has tapered bore, which allows stud to tilt; the large conical/radiused face of swivel block seats and swivels against depression in spotlamp body. i.e. this swivel block appears to go on lamp stud first, with its flat side visible. The stud can then pass through bracket at an angle and clamp block locks it at chosen lamp aimed angle. Only a few degrees tilt possible.

68693-38 SWIVEL WASHER (2) 41-84 Normal 3/8" flat washer .869 OD x .110" thick.

7778 LOCKNUT, (2) 3/8·16 x 7/16 high x 9/16hex, (2) normal 3/8" UNC Nyloc nut.

Well that's how I currently think it should work, someone else might know for sure, Identification in parts book is poor, service manuals say zip.

Nifty
spot mount.jpg
68720-62 clamp block.jpg
swivel block assy.jpg
68721-62 Swivel Block.jpg
Going by your first paragraph, it appears that I have the clamp block in the wrong place. I have it inside the turn signal mounting bracket 68523-68 (too many things called brackets in this book) between the locknut and the washer, where I can't see it doing anything allowing swivel. That seems to be the order in the parts book, but I've seen many times where they stick things where they fit best on the page and not necessarily where they belong in the assembly. Am I understanding you correctly that the clamp block goes on the outside top of 68523-68 with the radius facing up into the hole in the nacelle-mounted brackets? I can see how it would work this way. Thanks.

Jim
Mongrel505558
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Re: Adjusting Spot Lamps

#5

Post by Mongrel505558 »

Got it straightened out. Had clamp block in the wrong place in the assembly. Thanks, Nifty. It seems to go together just as you described.

Jim
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Re: Adjusting Spot Lamps

#6

Post by nifty »

I had a bit of a re-think, got it partly wrong and have edited below as per Jim's great cad drawing.
Spotlamp wire is threaded through all below parts.
Spotlamp & signal lamp assembly sequence, from top:
68652-64B PASSING LAMP, clear lens, 12v (Spotlamp, marked "Guide H SAE 0 62", chromed, cad rivets) with no hardware on stud.
68721-62 SWIVEL BLOCK, (2) 62-84; .614" small ID x .775" big ID x 1.375" OD x .338" high, radius upwards into spotlamp housing.
68795-68 CLAMP BRACKET (steel P clamp, if support bar used, 68603-68 etc if support bar not used),
68720-62 CLAMP BLOCK, (2) 62-84; .391" ID x .687" OD x .165" high, radius upwards, tip engages with underside of hole in P clamp, if support bar used, 68603-68 etc if support bar not used),
7145W Lockwasher* 3/8” (external tang shakeproof washer, used primarily for electrical ground)
68519-68 MOUNTING BRACKET, directional lamp (2) ,(chromed die-cast pedestal, signal lamp to spotlamp) 68-84
68693-38 SWIVEL WASHER (2) 41-84 Normal 3/8" flat washer .404" ID x .869 OD x .110" thick. washer goes inside 68519-68.
7778 LOCKNUT, 3/8" 16TPI x 7/16 high x9/16hex, (2) normal 3/8" UNC Nyloc nut. nut goes inside 68519-68.

*Note: In 61-78 & 41-84 parts manuals, the 7145W Lockwasher is shown between 68721-62 SWIVEL BLOCK and 68795-68 CLAMP BRACKET, but IMO the specified shakeproof washer would engage badly with .614" small ID of 68721-62 SWIVEL BLOCK.

Nifty
Last edited by nifty on Thu Sep 15, 2022 11:01 pm, edited 5 times in total.
Mongrel505558
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Re: Adjusting Spot Lamps

#7

Post by Mongrel505558 »

nifty wrote: Thu Sep 15, 2022 1:38 pm I've had a bit of a re-think, maybe...
Spotlamp & signal lamp assembly sequence, from top:
Spotlamp with bare stud
68721-62 SWIVEL BLOCK, radius upwards into spotlamp housing
68795-68 CLAMP BRACKET (steel P clamp, if support bar used, 68603-68 etc if support bar not used),
7145W Lockwasher 3/8” (external tang shakeproof washer against underside of P clamp, primarily for electrical ground)
68693-38 SWIVEL WASHER
68720-62 CLAMP BLOCK, radius upwards, tip engages with swivel washer
68519-68 MOUNTING BRACKET, directional lamp (2) ,(chromed die-cast pedestal, signal lamp to spotlamp) 68-84
7778 LOCKNUT, 3/8" 16TPI x 7/16 high x9/16hex, (2) normal 3/8" UNC Nyloc nut. nut goes inside 68519-68

Note: the 7145W Lockwasher is shown between 68721-62 SWIVEL BLOCK and 68795-68 CLAMP BRACKET , but the specified shakeproof washer would engage badly with .614" small ID of 68721-62 SWIVEL BLOCK.

Nifty
I went out and re-assembled it the way you described in your last post and it works fine. But by your account above I have the swivel washer in the wrong position, which makes sense: why would it be called a swivel washer if it didn't bear on the swivel block. I guess I'll pull it apart one more time. I'm getting quick at this job.

Thanks again.

Jim
Mongrel505558
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Re: Adjusting Spot Lamps

#8

Post by Mongrel505558 »

I drew it up roughly in AutoCAD really quickly. It's not so scale, but I tried to get the shapes right. I played with the positions of the parts and what I have installed on the bike right now is the order shown on the drawing. It works on paper and on the bike.
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Re: Adjusting Spot Lamps

#9

Post by nifty »

Great drawing Jim, awesome AutoCad skills
I have edited my earlier posts to synch with your drawing and added some more detail of the parts.
Nifty
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