Alfa Romeo/Alfa Romeo Digest Archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [alfa] S3 Spider speedo - update



Hi Tony:

What about the calibration of the tachometer? While the speedo in my '87 Spider is terribly slow, the tach actually reads fast, so in my case, I can't even use the tach to tell how far over the speed limit I'm driving. I understand that there is a similar trim pot in the tach, but I haven't had time to adjust either of the gauges. Odd thing is that the odometer is dead-on accurate.

BTW, have you seen this link?

http://www.alfabb.com/bb/forums/showthread.php?t=2902&highlight=S4+tachometer

Regards,

Dean
Lutz, FL
'74 & '87 Spider Veloce's


At 08:26 PM 8/7/2004, you wrote:

Date: Fri, 6 Aug 2004 17:46:02 -0400 (EDT)
From: "Anthony" <tg60@domain.elided>
Subject: [alfa] S3 Spider speedo - update

Dear All, In the process of resolving the lazy speedo problem on my graduate (87) so common on most S3 spiders I removed the trim pot from the speedometer, soldered a length of wire (~1.5ft)going from the speedometer to the pot so that I can put the cluster back together but have the trim pot dangling by the fuse panel so that I can tweek the pot without taking the whole thing apart ever again. I had some success whe the pot is turned all the way counter-clock-wise. I say "some" sucess because the speed is accurate at about 5% below normal speed (5th gear 3000rpm 59Mph, should read around 65MPH). The pot will not go any further. The resistence of the pot is now close to 0 ohms, essentially as if the pot wasn't even there. I think we can conclude that somewhere in the circuit the resistance has increased or some component in the circuit now need more juice to work. The trim pot tests OK, it's a 220 ohm resistance in the sweeping arm increases and decreases without dead spots. All solder connections are shiney.


tonyg
--
to be removed from alfa, see /bin/digest-subs.cgi
or email "unsubscribe alfa" to majordomo@domain.elided


Home | Archive | Main Index | Thread Index