Lubricant for speedometer "head unit" .

[ikeepmychevytoo]

Older units from 60's has a wick for lubrication. Mine '84 Chevy with cable driven speedo head seemingly has nothing devised for lubrication. There is a steel rod turning inside a copper/brass* bearing. *Indeed all I know is, its yellow. Needle is jumpy below 30 mph but after sitting a week it is smooth for the first fifty miles. So I think this is a lubrication problem. What do I use to lubricate it and how? Is it OK to spread grease to the edges of the bearing and wait it to penetrate? Some says non-congealing quality lube. What lube could be close to that, NLGI #2 lithium grase? (Cable, governor and related reduction gears replaced already.)

 

[ikeepmychevytoo]

My homework so far... The term for that bearing at the head unit was called sleeve bearing. A found a document which has a detailed info on lubrication mechanism (link is below if anyone interested -5th page). Acoording to the doc. that bronze material must be a sintered (porous) metal. So I guess since they contain fibers grease should be avoided (?). I will try engine oil next weekend and will see how it turns... I'm still looking forward for ideas on oil type. At best I'm a "naïve" on this. http://www.papstplc.com/downloads/referencebook/chapter11.pdf

 

[Gary Allan]

The only lub I've ever tried on cable driven speedos is graphite ..the stuff you use on locks. It would manage to work it's way in there. I don't recall if I ever owned a car long enough after I lubed it this way to really test how long it lasts ..but it was effective in those I used it on.

 

[srivett]

Maxima Non-Synthetic chain wax works well on speedo cables. It can be found at motorcycle shops. You spray it on and after a while it gets really thick and tacky. I wouldn't use it inside the truck before taking a smell of it because my bike always smells like the stuff. There's obviously a lot more of it on a bike chain but it's worth considering. Steve

 

[widman]

usually a good cleaning of the cable and sometimes the actual head 9with compressed air) starts things off right. Then we use graphite powder. So far I've been able to keep them working in off road conditions over 500,000 km this way.

 

[ikeepmychevytoo]

Thank you for sharing experiences... I think cable is sorted out which I've replaced last spring -it was cheap and I've already added graphite before installation. My problem is the head-unit, right now I brought it house, attached the drill to the old cable and now I'm trying to impregnate the tiny bearing with Castrol 20w 50 because some search for "sleeve bearing lubes" yielded lubes with similar viscosities at 100ºC. I have an M1 chain lube... may be I try it after. No problem with smells, I think gasoline and oil are the perfumes for the man's car This weekend I need to cover several hundred miles which would be a great after-test so I'm speeding up the process.