Peter Douglas Winn Posted March 25, 2019 Report Share Posted March 25, 2019 My speedo is playing about again. I know it is a cable run problem. How does one working on his own get it set up right. It seems to keep on changing its position inspite of cable ties. How do I check this stationary. When driving hand under the dash is great but I don't know what is happening under the Bonnet and when I stop I can't see any chnage of routing. Quote Link to post Share on other sites
John L Posted March 25, 2019 Report Share Posted March 25, 2019 Could it be the angle drive not running smoothly? Quote Link to post Share on other sites
Peter Douglas Winn Posted March 31, 2019 Author Report Share Posted March 31, 2019 I just don't know. I have never heard of that one. If nobody knows how to check the cable can anybody say which way the cable should run? I believe my cable is correct but I always assume that the majority know better. Quote Link to post Share on other sites
Mk2 Chopper Posted March 31, 2019 Report Share Posted March 31, 2019 How do you know it's the cable run? Unless there are some tight bends it should be fine. You mention under the bonnet are you talking about the tach, because the speedo cable goes to the gear box. Have you tried removing the cable at the instrument end and tried driving and observing how well it's turning in the housing? Also what are your symptoms that make you suspect the cable? Gareth Quote Link to post Share on other sites
Waldi Posted March 31, 2019 Report Share Posted March 31, 2019 Hi Peter, Have you applied some grease or oil in the cable? I always take new cables apart (pull the inner out), and apply some molykote (black) grease on the inner cable. Not too much, but enough to reduce friction. If you use too much grease, it may enter the speedo, which can result in failure, but a dry cable may tend to stick and then brake loose when revolving, resulting in unstable readings. The small amount of lubricant will drastically reduce friction, and lubrication will also reduce the load on the angle drive, which will last longer if you do. I know others do not recommend this, but this is what I do. Regards, Waldi Quote Link to post Share on other sites
Mk2 Chopper Posted March 31, 2019 Report Share Posted March 31, 2019 39 minutes ago, Waldi said: Have you applied some grease or oil in the cable?...I know others do not recommend this, but this is what I do... That's exactly what the Smiths instruments manual says to do. They go on to say about withdrawing the cable after greasing it and wiping the last part near the speedometer back off again. And it's part of preventative maintenance you should carry out at regular intervals. Gareth Quote Link to post Share on other sites
Mike C Posted March 31, 2019 Report Share Posted March 31, 2019 The cable shouldn't jump around. I like to let the cable find it's own route as much as possible, without tight bends and ties. Try greasing is as described above but wipe the grease away from the last 200mm or so of cable at the instrument end. Don't overlubricate -I let excess cable grease enter a tacho a few years ago and it ran for about an hour before it started to read wildly high. Quote Link to post Share on other sites
Peter Douglas Winn Posted March 31, 2019 Author Report Share Posted March 31, 2019 20 years ago I bought a bowden cable greaser and I have never bothered to use it. Perhaps I should. I know it is the speedo as the speedo flickers and makes a noise. When I put my hand under the dash when driving (slowly) I can shift the lay of the cable and the noise vanishes. Unfortunately it always springs back to the noisy position. Hence my original question. I don't know what is happening when I put my hands under the dash, I need a second person to look into the engine bay. I don't have that person. I have checked to see if there are any sharp bends, I could not find any, all were within the curve radius limits. Quote Link to post Share on other sites
RogerH Posted March 31, 2019 Report Share Posted March 31, 2019 Hi Peter, I had that noise on the tacho cable. very careful alignment sorts it out. I used a cable tie, loosely applied and tightened bit by bit till I found the right place. I think the problem is in the receptacle in the back of the gauge. It needs to rotated and be just very very lightly lubricated. When it dries up then the chattering begins. Perhaps a dry teflon lubricant will work. Roger Quote Link to post Share on other sites
Mk2 Chopper Posted March 31, 2019 Report Share Posted March 31, 2019 1 hour ago, Peter Douglas Winn said: 20 years ago I bought a bowden cable greaser and I have never bothered to use it. Perhaps I should. I know it is the speedo as the speedo flickers and makes a noise. When I put my hand under the dash when driving (slowly) I can shift the lay of the cable and the noise vanishes. Unfortunately it always springs back to the noisy position. Hence my original question. I don't know what is happening when I put my hands under the dash, I need a second person to look into the engine bay. I don't have that person. I have checked to see if there are any sharp bends, I could not find any, all were within the curve radius limits. I'd definitely pull the inner cable out and lubricate, again not up to the speedo as has been mentioned. Does your trip and odometer work by the way? Have you tried slightly loosening the cable nut at the speedo end? Gareth Quote Link to post Share on other sites
Peter Douglas Winn Posted April 1, 2019 Author Report Share Posted April 1, 2019 Yes they both work well. I will print out ev erything that has been said and go to the garage and have a play. Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.