Andydodge Posted February 13, 2010 Report Share Posted February 13, 2010 Ever since I have had the 41 Plymouth Coupe its suffered from bouncing speedo needle syndrome, have tightened then loosened the knurled nut thing at the dash end of the speedo cable, have shot some lubricant down the inner cable, have now disconnected the cable from the speedo, and with the clock plate removed I can see that the inner cable is spinning freely thru the clock plate hole........am gunna do battle with the dogs breakfast that passes for wiring tomorrow morning and remove the speedo caseing from the instrument shell. Whilst I realise that the 1941 speedo is different to the later ones has anybody got any tips, tricks, voodoo spells, curses, discussions of parentage or general info that may help in the diagnosis of Bouncing Speedo Needle Syndrome.......apart from the constant noise of the needle bashing itself stupid against the right hand 100mph side of the speedo its also getting to be a pain watching the needle waving back & forth........this happens from about 10mph onwards & at a constant 30-40mph it shows whatever speed it likes.........lol.......anyway, any help would be appreciated........btw I have tried to do a search thru the site for previous posts on this topic without success.........thanks, Andy douglas Quote Link to comment Share on other sites More sharing options...
chopt50wgn Posted February 13, 2010 Report Share Posted February 13, 2010 I have used lubricants for speedos as well.........still had the needle bounce. So I took the cable out and applied a good grease to the whole cable. Having it coated well seemed to stop the bouncing. You could actually take a grease gun with a needle type fitting, the one you would use to just push the ball in on a zerk fitting. Then just shoot grease into the speedo cable liner. Quote Link to comment Share on other sites More sharing options...
greg g Posted February 13, 2010 Report Share Posted February 13, 2010 Usually a bouncy needle is related to a cable needing lube. You unscrew it from the speedo then pull the worm out. Be carefull asit is easy to get the old dirty lube all over yourself and the interior of your car. Pull it out, clean it with a solvent, I sprayed mine with throttle body cleaner. then re lube it with graphite grease or white litium, and then put it back in. there is also an assembly with a wick in it on the rear of the speedo that should be lubed with light oil like 3 in 1, clipper or sewing machine oil works well aslo. Quote Link to comment Share on other sites More sharing options...
P-12 Tommy Posted February 13, 2010 Report Share Posted February 13, 2010 Usually a bouncy needle is related to a cable needing lube. You unscrew it from the speedo then pull the worm out. Be carefull asit is easy to get the old dirty lube all over yourself and the interior of your car. Pull it out, clean it with a solvent, I sprayed mine with throttle body cleaner. then re lube it with graphite grease or white litium, and then put it back in. there is also an assembly with a wick in it on the rear of the speedo that should be lubed with light oil like 3 in 1, clipper or sewing machine oil works well aslo. I totally agree. I've always pulled mine from the housing and lubed the whole thing and put it back in and it works fine.Tom Quote Link to comment Share on other sites More sharing options...
aero3113 Posted February 13, 2010 Report Share Posted February 13, 2010 You can pull the worm out without disconnecting the cable from the trans? Quote Link to comment Share on other sites More sharing options...
greg g Posted February 13, 2010 Report Share Posted February 13, 2010 yes Quote Link to comment Share on other sites More sharing options...
aero3113 Posted February 13, 2010 Report Share Posted February 13, 2010 Good to know. Thanks:D Quote Link to comment Share on other sites More sharing options...
BobT-47P15 Posted February 13, 2010 Report Share Posted February 13, 2010 Maybe someone should invent automotive "post it notes" that we can stick on our cars to remind us of things needing attention. Quote Link to comment Share on other sites More sharing options...
claybill Posted February 13, 2010 Report Share Posted February 13, 2010 best thing...take the cable off at both ends...pull the inner out AND INSPECT FOR frayed ends sticking out...SOAK the outer cable in gas to clean out the inside. now you can install the metal nner cable with something that will have 12 month operation..most grease thickens and then it will stick again. try grafite as on door locks. OR; NAPA and others sell an 'inner speedo kit' NOT made of metal that will not corrode or hang up on the outer cable as it spins..$7.00 motorcycle shops sell thin nylon tubes to put over the inner cables so they dont rub and fray against the outer, and so on.. bill RE-ROUTE YOUR CABLE FOR BEST EFFICIENCY....NO BENDS. maybe you need a alonger one.? Quote Link to comment Share on other sites More sharing options...
Andydodge Posted February 14, 2010 Author Report Share Posted February 14, 2010 Well, undid the outer cable from the speedo and after pushing the whole cable assembly back thru the firewall into the engine bay was able to pull the inner cable or worm out of the outer cable.......seemed fine with even a light wipe of grease, cleaned all that off with mineral turpentine then wiped the whole inner cable with a light coating of moly grease, also squirted a light machinery oil into the outer cable & reinstalled the inner cable.....what a lovely messy job....took it for a drive......bounce, bounce, bounce.......lol.....buggar!!.....back to the bench.......pulled the spare instrument cluster I have down from the shelf, removed the speedo that hasn't seen a car for 25 yrs, cleaned and relubed the speedo drive, connected a low speed drill up to the speedo drive(after duly noting that its left hand driven).... and this speedo works well, trip meter doesn't move but I can live with that............so dive under the Plymouth dash again( jeese I'd forgotten that I'm 55, 56 next wednesday....lol)........remove the old speedo, compare it to the "new" one........the old one has a LOT more movement in the actual drive where the cable attaches at the back, and with the drill attached at a low speed just bangs itself against the 100mph mark........therefore it must be the speedo I say to myself...........O/k........with "new" speedo in hand its under the dash I go...........lol...........get the speedo mounted then have the joy of trying the get those 1/4" long screws back into the rear of the instrument cluster whilst upside down head wedged into the clutch pedal........what mopar designer decreed that these screws had to be this size!!!........even more fun as I wear glasses(have done so for 40yrs but now they are multifocal...lol)..............anyway I eventually get it all assembled and screwed down........take it for a drive round the block or so........within 100 yards I'm doing the happy, happy, joy, joy, dance..........NO BOUNCE........YES I AM GOD!!!..........lol.........well maybe not, but close.......lol...........anyway its fixed and I'd like to convey to ALL my friends on this forum my sincere thanks for putting up with my questions and passing on their knowledge & experience..........am a happy camper......Andy Douglas........btw its 5pm Sunday arvo here in Sunny Sth Grafton, East Coast of Oz......104F in our kitchen....stood outside in the sun for 5 minutes with the thermometer and it got to 116F.......lol....any spare snow?.....andyd Quote Link to comment Share on other sites More sharing options...
BobT-47P15 Posted February 14, 2010 Report Share Posted February 14, 2010 Well, Andy......sounds like ya did good. Hopefully the speedo will continue to function as it should. Quote Link to comment Share on other sites More sharing options...
claybill Posted February 14, 2010 Report Share Posted February 14, 2010 good work...and great docu-drama! bill a freighter full of snow is on the way.. Quote Link to comment Share on other sites More sharing options...
claybill Posted February 14, 2010 Report Share Posted February 14, 2010 good work...and great docu-drama! a freighter full of snow is on the way.!.we will dump it along the port..you can pick it up anytime there.. bill Quote Link to comment Share on other sites More sharing options...
Mechanik Posted February 14, 2010 Report Share Posted February 14, 2010 Nice job! Now ya need to dissect that old speedo and find out what the culprit really was. Quote Link to comment Share on other sites More sharing options...
John Mulders Posted February 14, 2010 Report Share Posted February 14, 2010 Don't forget to put a drop of oil in the speedometer aswell. See post : http://www430.pair.com/p15d24/mopar_forum/showthread.php?t=5766&highlight=speedo John Quote Link to comment Share on other sites More sharing options...
Niel Hoback Posted February 14, 2010 Report Share Posted February 14, 2010 Goodonya, Andy. Nuthin like determination. Quote Link to comment Share on other sites More sharing options...
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