Hey everyone! Been driving the car around a little lately. Noticed that the tach needle seems to be lower than anticipated - reading around 700 or so at idle (last year it indicated around 1000, engine still sounds the same), and at around 60 mph, the tach is reading around 2k, should be around 3k (in 3rd gear). Every now and then the tach needle will "jolt" up to the higher RPM, only to return to the original (incorrect) revs a short time later. A TR mechanic said that TR tachs do that, especially when cold. He said that it's the tach itself sticking, vs the sending units. So, what are your thoughts? Where's the first place to look to remedy this problem? Thanks, as always!
your tech is likely correct - it sounds like a mechanical issue rather than electronic. presumably the instrument can be opened up and checked and/or lubricated(?) if so... I'd suggest it be done sooner rather than later. If it is a mechanical issue, these things get exponentially worse over time. Catch it while you can! vincenzo PS: I do not know if the tach is 'serviceable' - if not, run 'till it quits!
Joe, call Mo-ma Manufacturing and speak with Joey Lobo. Sent him my tach as it was behaving as yours was, he replaces the circuit board for around $300. Also, sent him my speedo to test as I had the dash apart, he called me said it was fine but sometimes they do have to replace the grease in the gears and he didn't charge me. I had read a few posts prior to calling him and he is a great guy, shipped my stuff back in less than a week too. Home Good luck Jeff
Read this thread, sounds like your problem: http://www.ferrarichat.com/forum/mondial/262520-88-mondial-tachometer.html From post #7: "4. Repair the tach. The tach is pretty much solid state with only a few moving parts that are essentially contact-less and/or self lubricating. However, you'll see there is a potentiometer with a little blob of silicon sealant on it (to hold the dial adjuster in place) which has a rheostat type contact. Mark the location of the rheostat with a fine marker. I believe this contact gets dirty or oxidized over time, and causes the gauge to read incorrectly, or not at all. Simply move the adjuster back and forth (gently) for a good 30 seconds and the contacts will self-clean." Alden
Joe, I had the exact same issue as you. It would behave normally at the beginning of the drive and then start to under report RPM's while making random jumps to the correct RPM's. I took it North Hollywood Speedometer. They replaced the circuit board and swapped out all the little lights while they were in there. Total bill was $220 if memory serves. I described the issue over the phone and the guy said no problem sounds like the circuit board bla bla bla no problem we have the parts. North Hollywood Speedometer | NH Speedometer
You might check this out. I have one and it's perfect ; http://www.dinoplex.org/tachoconversion/index.html Sent from my iPhone using Tapatalk
Wow, looks cool - did you purchase a new circuit board then? If so, where? He mentions on that page that he doesn't sell them.
You should contact him by PM. At the time I did mine and new speedo board as well he was selling them. I think he sells them now to the gauge shops like Palo Alto and others. I'm sure he will respond on where and how to obtain them. Also be sure to ask him for the proper resistors and calibration for twelve cylinders. Full website dinoplex.org also he has posted a lot of info in the 308 section.
