[dmickeyjr]

I have had this spider for four or five years and I am just now driving it enough that this bothers me. The speedo in this car has always read approx twice the speed I am actually going. Anyone with any input on what I need to do to remedy this issue would be greatly appreciated.

 

[Vintre]

Usually the speedo or tach reads slow, but this thread is the one you want.

How to fix your slow reading speedometer tachometer

It takes a few tries to get it right.

I used a GPS to verify each time I went out to see what speed I was actually going.

Good luck.

Vin

 

[Archangel]

I have the same problem of it reading faster than i am actually going but.. The speedometer that they are talking about is from a later car not a 84, It seems like the one they are working on is electronic where the one for the 84 and below spiders are mechanical. If i could find out how to adjust Our mechanical ones to read correctly it would really help. On the 84 and early you had duel pods not a monopod.

Angel

 

[Tifosi]

85 and down for mechanical speedos.

There's an adjuster deep, deep within the innards of the thing that is used to calibrate the gauge via the amount of tension the clock spring has. Likely somethng you really don't want to frig with unless you've got uber confidencein your bezel removal and clockworks skills.

Someone had a nice writeup with pix (Wille R. IIRC) on how to do it on the older version gauges, but I'm not sure if it applies exactly to the Jaeger gauges the S3's have.

That being said, one 'could' pop the bezel and glass then run the indicator needle around full clockwise then very carefully trip the tip of it over the stop pin down by 10mph so that its basically wound one rotation tighter.
Whether it would be right, (prolly not), or the needle would break, (good probability), or any number of other not so good type scenarios, if nothing else it will indeed cause the needle to read slower (possibly way too much so even)

IIRC Palo Alto are the folks to talk to about getting things properly tuned in mechanical gauge heads if you want to farm it out to someplace that has the right tools and such.

 

[dghii]

Of course, if your spider is red, it really is going that fast!

 

[MJB]

Same problem with tach and squeaky speedo

Basically, can one make adjustments manually or am I looking at new pieces? A reply above talks about "pop" the plastic fron off and turn the dial clockwise. Maybe I should try that with my speedo. Anyone experience a squeaky speedo before. **** irritating.

 

[ghnl]

The link in reply #2 is for the later 'monopod' instrument. Your '85 should have the earlier dual pods. I think the easiest fix would be to find a good used replacement speedometer. Try the parts for sale section of the BB, browse eBay or call Alfa Parts Exchange.