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Oily speedo

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Jeepster

Jeepster

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Last autumn the speedo failed in my BJ8, so I whipped it out and had it rebuilt by Speedy Cables here in the UK. Looks like they did a great job as it was returned and looked good as new ( probably better than new)

Just before it failed I noticed a very black and thin grease drip from the speedo. This was all over the rear of the case when I removed the unit.

The guy at the restorers mentioned that oil could be drawn from the gearbox up the speedo cable and into the speedo causing the failure. He said that as the mess on the rear of my speedo was more greasy and black, it more probably that it was graphite grease and not oil from the gearbox.

When the the unit was returned there was a note to say that oil was found in the speedo and I should replace the seal between the gearbox/cable.

Im happy to replace the cable as a matter of course, but I can’t see anything about a seal or anything to stop the oil going up the cable?
Has anyone else experience this? The gearbox has the correct level and is not over filled.
 
Jeepster,

I doubt transmission oil was the lubrication traveling up the cable, especially if you are using an angle-drive.

A while ago I experienced a black gum in my speedometer and believe the penetration was the result of over-lubrication when installing a new cable. Over an extended period, I believe the excessive graphite-based gel traveled over the cable to penetrated and contamination the gauge. the extended period or contamination allowed evaporation of the lubricant gel to form a black (graphite) gum to form and caused the gauge to malfunction.

Although their may be a seal embedded within the shielding of the speedometer cable, I have concluded that using only a small amount of graphite lubricant has eliminated this as a problem for me. To validate that conclusion, after cleaning, I have not had a re-occurrence of the issue for the past 5 years.

Sorry I can't be more definitive,
Ray(64BJ8P1)
 
Disclaimer: This is hearsay: there were reports of speedo cables that were wound the wrong way; i.e. so as to cause oil to creep up the cable from the gearbox.

I just replaced the seal in my BJ8's gearbox speedo drive (the part that meshes with the planetary gear carrier, I think). The new seal did not fit well, and required some 'persuasion.' The new seal, from Moss, reminded me of the new seals sold for the gearbox rocker shaft; i.e. green shell, and not fitting well, as opposed to the correct, original seals which have a thicker shell that is shiny metal. I hope I don't have the same problem as you. FWIW, I've had good luck with spray silicone lubricant on the cable.
 
Bob,

I like the idea of using silicone spray. Are you just spraying the inner cable and installing in in the sheath?

Are you saying that the faulty transmission seal can cause trans oil to be pushed up the cable to the speedometer? If you are using an angle-drive out of your transmission, I really can't see how transmission oil could be pushed through the angle drive and up the cable without leaking on the ground to show a problem.

Ray(64BJ8P1)
 
I had the same thing happen to my tach drive. There is a seal where the cable engages with the drive and when it failed oil augured up the cable, into the tach head and eventually down upon my knee. I was travelling back from CA when the seal failed and luckily Dave Porter in Albuquerque fixed me up in his shop. That was 15 years and about 50K miles ago and the seal is still intact.
 
RAC68 said:
Bob, ... I like the idea of using silicone spray. Are you just spraying the inner cable and installing in in the sheath?
Click to expand...

Yeah. But, last time I had the whole cable assembly out I cleaned the outer sheath out with solvent before soaking the cable in silicone lubricant from a spray can. I like silicone lubricants--in some applications, like starter Bendixes--because they seem to attract less dirt than petroleum-based oils. I think the silicone actually dries and leaves a film. I've used it to lubricate the inner workings of speedos, too.

Graphite is good, too, but I usually make an unholy mess with it.
 
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Hi All,

To identify the wrong way twisted cable, which way is the correct twist of the driving speedometer cable?

Ray(64BJ8P1)
 
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