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Another Horror on Harold's Underside

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jjbunn

jjbunn

Jedi Knight
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Every time I crawl underneath Harold I seem to find something I don't like the look of.

Here is what appears to be the speedo cable, hanging loose, attached by a cable tie (yellow arrow). The red arrow points to the attachment point for the cable, which I noticed has hardly any thread on it. Time to get out the Bentley manual again!

306112137_cf75311f52_o.jpg
 
I can't quite figure this out. Isn't it supposed to be square drive? And isn't the transmission side supposed to be female? It is on my early gearboxes.

Maybe the female square drive somehow pulled off and that's the end of the pin we see? Just doesn't look right.
 
steve's correct.
The nylon speedo pinion housing is broken off. They are NLA by the catalogs I have which means they must have sold out of the junk that they were selling a few years ago. Off to the salvage yard.
 
My guess is that a DPO tried to glue up the housing (the outer sleeve of the dangling bit) onto the speedo gearbox flange and used a zip tie to secure it. Or not /ubbthreads/images/graemlins/smile.gif

Lets see what the good Doc says.
 
That's the 90 degree adapter hanging loose. It's broken the speedometer drive "housing" in half. The housing, when it's in one piece, bolts into the tranny, and the 90 degree adapter screws onto it, then the speedo cable screws onto that. Moss # 433-750. Availability N/A.
 
Thanks everyone. I think I'll detach the damaged parts so that I can assess the problem more easily. Can I undo the two bolts on that flange to extract it, without getting soaked in oil?
 
Was time to drain the transmission anyway.
 
Julian, Drain the transmission of oil. As Jack said, It's time anyway. Pull out the gear base and contact Tony or someone more local who has a used one. They are not available new. Also, if the angle drive is good, I'd clean it out before reinstalling it. Probably full of crud. PJ
 
Lots of places to check for this used part on both coasts.
 
[ QUOTE ]
Also, if the angle drive is good, I'd clean it out before reinstalling it. Probably full of crud. PJ

[/ QUOTE ]

Good time to lube the cable too. I've got a DIY saved somewhere that explains how. Something about hanging the cable from the ceiling and using a ziplock bag full of oil. Can't seem to find it at the moment. Must be getting old /ubbthreads/images/graemlins/blush.gif.
 
Yup... pull the two bolts, out with the gear drive. That piece is on the tailshaft and unless the car is in a "nose-up" attitude you don't really ~need~ to drain the box. Some oil will come out anyway. It's a nylon or suchlike housing and has apparently been broken off. Hopefully Tony will have one. Is the broken threaded bit still in the speedo angle drive? I see what looks like the cable end broken in the center of the gear drive shaft... argh. There was a time those angle drives were "Unobtanium" too. At least that is now replaceable. If it were my car I'd replace cable, too. Slop the inner cable up with "Molykote" or similar lubricant on assembly.
 
I extracted the pinion:
307076462_3a7cef1fed.jpg


The gear has 26 teeth.

A guy on Ebay has several different sorts, including a 26 teeth version, so I ordered it: it looks right

75_1.JPG


I haven't managed to detach the cable from the angle yet: it's being PB Blasted :smile:
 
Yep, 26 tooth - I've got a few....but the one you pictured looks good.
 
[ QUOTE ]
Yep, 26 tooth - I've got a few....but the one you pictured looks good.

[/ QUOTE ]

Hi Tony, Any update on whether you have the other items I sent you a list of?
 
Julian - was out most of holiday - have some, will locate remainder this week & get you a PM
 
I'm having the Devil of a game trying to remove the angle drive off the end of the speedo cable. Are there any tricks here? I've PBBlasted it for a day or two. But there doesn't seem to be much to hold on to. Presumably the knurled ring unscrews from the angle drive?

Thanks for any tips!
 
Yeah, the angle drive is a "transition" bit. From what you've photo'd it's a scrap bit in any case (square end broken off in the pinion drive shaft). You'll need a new cable, angle drive and the bits wot go into the tranny. It's a "bite the bullet" scenario. The bits from the speedo head on down to the tranny pinion are FUBAR'd.

"ungood"... but ~so~.
 
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