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Speedo drive progress report, Julian?
- Thread starter DrEntropy
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jjbunn
Jedi Knight
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It's dark by the time I get home from work, so I haven't had a chance to have another go at it yet. Tomorrow I hope to be able to at least remove the angle drive so that I can see if it needs replacing.
Also on the agenda tomorrow is fitting the new rear brake hose and LH/RH brake pipes, and new brake shoes, which arrived from Moss earlier this week.
Also on the agenda tomorrow is fitting the new rear brake hose and LH/RH brake pipes, and new brake shoes, which arrived from Moss earlier this week.
jjbunn
Jedi Knight
Offline
So, here is the angle drive:
One problem in getting it off is that the knurled/threaded sleeve connector on the speedo cable is so thin, if you grip it with any force then it distorts a little and wont turn.
Anyway, as you can see I have pulled some wires out of the angle driver. What are they doing in there? I was expecting to see a square metal boss: but all I see is these wires.
The thing is almost certainly kaput. I need a replacement!
(By the way, what is the small screw for on the side of the angle drive?)
In better news, I finished replacing the rear brake lines, left and right, and the small flexible hose. That went quite well.
The screws that hold the brake drum on to the hub on the passenger side are seized. They are posidrive/Philips, and the holes are burred, so I can't apply much turning force without burring them more :-(
I think I need an impact screwdriver: would that help?
One problem in getting it off is that the knurled/threaded sleeve connector on the speedo cable is so thin, if you grip it with any force then it distorts a little and wont turn.
Anyway, as you can see I have pulled some wires out of the angle driver. What are they doing in there? I was expecting to see a square metal boss: but all I see is these wires.
The thing is almost certainly kaput. I need a replacement!
(By the way, what is the small screw for on the side of the angle drive?)
In better news, I finished replacing the rear brake lines, left and right, and the small flexible hose. That went quite well.
The screws that hold the brake drum on to the hub on the passenger side are seized. They are posidrive/Philips, and the holes are burred, so I can't apply much turning force without burring them more :-(
I think I need an impact screwdriver: would that help?
rick_ingram
Yoda
Offline
I had to use an impact driver to get those screws off of my MGB years ago....it worked well...You don't really need them, so don't replace them upon reassembly...or at least use antiseize on the NEW screws that you put back in!
tony barnhill
Great Pumpkin - R.I.P
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Should've been a solid metal boss inside it, you're right...looks like you've been DPO'ed again!
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... Or Dumb, or Damned .... /ubbthreads/images/graemlins/wink.gif
R.
R.
OP
Offline
"Dreaded" works fer me.
That's a nasty lookin' angle drive... appears the cable or something further 'upstream' failed first. The wires are pieces of the frayed cable end. From the 'evidence' you may have a seized cable or speedo head. I don't recall the change-point but there was an angle drive added at the back of the instrument on later B's. "Later" to me is anything after '68, BTW. /ubbthreads/images/graemlins/wink.gif
That's a nasty lookin' angle drive... appears the cable or something further 'upstream' failed first. The wires are pieces of the frayed cable end. From the 'evidence' you may have a seized cable or speedo head. I don't recall the change-point but there was an angle drive added at the back of the instrument on later B's. "Later" to me is anything after '68, BTW. /ubbthreads/images/graemlins/wink.gif
I would suggest you pull the speedo drive in the transmission. Quite a chore to get to with the tranny in the car. You will need some delicate fingers to reach the rear bolt. From my experience those frayed wires mean the gear in the tranny has something blocking it from turning. Putting a new angle drive in will just wreck the new angle drive, and they are not cheap. When you pull the drive from the tranny I suggest doing it with oil in the tranny. It is meesy but it helps wash out whatever was in the way. Look around your catch pan when you are done to see what it might have been (metal chunk or ?).
If you want to see if your speedo is OK, have your new cable attached to the speedo then run a drill (in reverse) on the loose end of the cable. If you get mileage it works. Or if you have a helper they can tell you if you are generating mph.
If you want to see if your speedo is OK, have your new cable attached to the speedo then run a drill (in reverse) on the loose end of the cable. If you get mileage it works. Or if you have a helper they can tell you if you are generating mph.
jjbunn
Jedi Knight
Offline
[ QUOTE ]
I would suggest you pull the speedo drive in the transmission. Quite a chore to get to with the tranny in the car. You will need some delicate fingers to reach the rear bolt. From my experience those frayed wires mean the gear in the tranny has something blocking it from turning. Putting a new angle drive in will just wreck the new angle drive, and they are not cheap. When you pull the drive from the tranny I suggest doing it with oil in the tranny. It is meesy but it helps wash out whatever was in the way. Look around your catch pan when you are done to see what it might have been (metal chunk or ?).
If you want to see if your speedo is OK, have your new cable attached to the speedo then run a drill (in reverse) on the loose end of the cable. If you get mileage it works. Or if you have a helper they can tell you if you are generating mph.
[/ QUOTE ]
Interesting ... thanks for the input. I'm not quite clear on this: I have pulled out the pinion by detaching it from the transmission. I have a replacement. Are you suggesting that there may be something inside the transmission that prevents the pinion from turning? If so, why would that cause a problem in the angle drive (since nothing would be going on inside the angle drive: no motion). Or are you referring to the pinion itself? I think I may have misunderstod what you are referring to?
I would suggest you pull the speedo drive in the transmission. Quite a chore to get to with the tranny in the car. You will need some delicate fingers to reach the rear bolt. From my experience those frayed wires mean the gear in the tranny has something blocking it from turning. Putting a new angle drive in will just wreck the new angle drive, and they are not cheap. When you pull the drive from the tranny I suggest doing it with oil in the tranny. It is meesy but it helps wash out whatever was in the way. Look around your catch pan when you are done to see what it might have been (metal chunk or ?).
If you want to see if your speedo is OK, have your new cable attached to the speedo then run a drill (in reverse) on the loose end of the cable. If you get mileage it works. Or if you have a helper they can tell you if you are generating mph.
[/ QUOTE ]
Interesting ... thanks for the input. I'm not quite clear on this: I have pulled out the pinion by detaching it from the transmission. I have a replacement. Are you suggesting that there may be something inside the transmission that prevents the pinion from turning? If so, why would that cause a problem in the angle drive (since nothing would be going on inside the angle drive: no motion). Or are you referring to the pinion itself? I think I may have misunderstod what you are referring to?
Sorry. I figured I was not being too clear. Especially since I tend to call parts thingamajig and whatsit. I was suggesting you pull out the pinion.
It does seem counterintuitive that the pinion is causing the angle drive problem. But I went throught the same thing. I assumed it was the speedo or the cable that shredded the angle drive, so replaced the angle drive and cable, checked that the speedo was turning, put the parts back in.
Went for a drive found nothing working, took it apart to find another shredded angle drive, pulled the pinion, washed a sliver of metal out, put it back together with new angle drive, and now it worked.
Never bothered to analyze what caused the problem, just happy it was working.
I had the same problem on another car too, the speedo and cable worked when tested on their own just not all together. Pulling out the pinion and putting it back in fixed the problem there too. I was thinking
I thought I had read that you had checked that the problem was not at the speedo end, but maybe I just assumed that.
Did you get a new angle drive as well as the replacement pinion?
Don
It does seem counterintuitive that the pinion is causing the angle drive problem. But I went throught the same thing. I assumed it was the speedo or the cable that shredded the angle drive, so replaced the angle drive and cable, checked that the speedo was turning, put the parts back in.
Went for a drive found nothing working, took it apart to find another shredded angle drive, pulled the pinion, washed a sliver of metal out, put it back together with new angle drive, and now it worked.
Never bothered to analyze what caused the problem, just happy it was working.
I had the same problem on another car too, the speedo and cable worked when tested on their own just not all together. Pulling out the pinion and putting it back in fixed the problem there too. I was thinking
I thought I had read that you had checked that the problem was not at the speedo end, but maybe I just assumed that.
Did you get a new angle drive as well as the replacement pinion?
Don
trrdster2000
Luke Skywalker
Offline
The little screw is for getting grease in the angle drive which should be done with each greasing of the car. There is a plate on the TR's to help get at this on the rear of the tunnel, but the angle drive is only used on the overdrive cars. The wires hanging out have come from the angle drive connection to the speedo gear as it's only a cable like the speedo cable inside the angle drive and silver solder in place. They can be replaced but most of the time it will mess the little gears up when it brakes. Wayne
jjbunn
Jedi Knight
Offline
[ QUOTE ]
The little screw is for getting grease in the angle drive which should be done with each greasing of the car. There is a plate on the TR's to help get at this on the rear of the tunnel, but the angle drive is only used on the overdrive cars. The wires hanging out have come from the angle drive connection to the speedo gear as it's only a cable like the speedo cable inside the angle drive and silver solder in place. They can be replaced but most of the time it will mess the little gears up when it brakes. Wayne
[/ QUOTE ]
Hi Don,
Yes, I have all three bits now: the pinion and plate etc., the angle drive, and a new cable.
I think you are probably right that the pinion was the problem, since the angle drive and cable turn very freely.
I shall see this weekend, when I assemble the new parts
The little screw is for getting grease in the angle drive which should be done with each greasing of the car. There is a plate on the TR's to help get at this on the rear of the tunnel, but the angle drive is only used on the overdrive cars. The wires hanging out have come from the angle drive connection to the speedo gear as it's only a cable like the speedo cable inside the angle drive and silver solder in place. They can be replaced but most of the time it will mess the little gears up when it brakes. Wayne
[/ QUOTE ]
Hi Don,
Yes, I have all three bits now: the pinion and plate etc., the angle drive, and a new cable.
I think you are probably right that the pinion was the problem, since the angle drive and cable turn very freely.
I shall see this weekend, when I assemble the new parts
jjbunn
Jedi Knight
Offline
[ QUOTE ]
"Dreaded" works fer me.
That's a nasty lookin' angle drive... appears the cable or something further 'upstream' failed first. The wires are pieces of the frayed cable end. From the 'evidence' you may have a seized cable or speedo head. I don't recall the change-point but there was an angle drive added at the back of the instrument on later B's. "Later" to me is anything after '68, BTW. /ubbthreads/images/graemlins/wink.gif
[/ QUOTE ]
Question about refitting: under the car, does the speedo cable clamp to anything? It's attached to the angle drive, so that sort of holds it in place, but I'm wondering if there should be a cable clamp nearby? There wasn't when I removed the old one ...
"Dreaded" works fer me.
That's a nasty lookin' angle drive... appears the cable or something further 'upstream' failed first. The wires are pieces of the frayed cable end. From the 'evidence' you may have a seized cable or speedo head. I don't recall the change-point but there was an angle drive added at the back of the instrument on later B's. "Later" to me is anything after '68, BTW. /ubbthreads/images/graemlins/wink.gif
[/ QUOTE ]
Question about refitting: under the car, does the speedo cable clamp to anything? It's attached to the angle drive, so that sort of holds it in place, but I'm wondering if there should be a cable clamp nearby? There wasn't when I removed the old one ...