Hitman's Pontiac Trans Am Forum

Trans Am Information => Trans Am Tech => Electrical => Topic started by: Crisis on November 15, 2018, 03:06:53 PM

Title: Speedometer doing weird things
Post by: Crisis on November 15, 2018, 03:06:53 PM
Hello,

I've a '79 TA with a 403ci. I've replaced my old speedometer by a new one which do strange things.
When i drive Under 45mph, the speedo is under the real speed. Beyond 45mph, the speedo is upper the real speed. The more I accelerate, the upper he becomes. When I drive at 70mph, it shows 80mph. the needle don't bounce but looks free, moving to right and to left when i Accelerate and decelerate fast and quickly.
And the miles counter is very fast. When I drive on 5 miles, the counter adds 30 miles...

Wires good and speedogear is the good one (regarding my wheels, the speedgear into my transmission and the ratio of rear axle).
Is my speedometer is dead ?

Is anybody has an idea about this ?

Thank you all

Chris

(sorry for my english)
Title: Re: Speedometer doing weird things
Post by: Nexus on January 06, 2019, 09:47:52 AM
There is a small gear on the transmission...you'll have to replace this gear with the next size down or the next size up to calibrate it properly. There generally several suppliers around that can help with this...that is if you are completely sure it isn't the speedo cable being broken!!
Title: Re: Speedometer doing weird things
Post by: Wallington on January 06, 2019, 05:30:01 PM
This was on another forum, I think he got it sorted. The miles added was incorrect, which threw most off.
Title: Re: Speedometer doing weird things
Post by: Nexus on January 07, 2019, 07:45:09 PM
Ahh...ok...perfect...glad it's been solved
Title: Re: Speedometer doing weird things
Post by: Crisis on January 23, 2019, 02:02:49 PM
Hello !

Sadly, it has not been resolved and it's not a gear size problem.
My brand new speedo has never worked as it should. =(
The needle is floating and shows wrong speed because of a too much relaxed spring.
Title: Re: Speedometer doing weird things
Post by: Nexus on January 25, 2019, 05:32:24 AM
Ahh...so the next question comes up...How do you fix that?

Need to send it to someone or can you try and resolve it on your own?
Title: Re: Speedometer doing weird things
Post by: Crisis on February 09, 2019, 07:35:04 AM
Hello,

Classic Industries seems to be OK to send me a tested brand new one...
Wait  & see. =p

Regards
Title: Re: Speedometer doing weird things
Post by: Crisis on February 12, 2019, 05:06:11 PM
Hello again,

I juste want to write that I'm impressed by the kindness of Classic's team which is testing a new speedo before sending it to me.  :o

Chris
Title: Re: Speedometer doing weird things
Post by: Nexus on February 16, 2019, 09:20:26 PM
That's great indeed. I haven't heard of too many negative things. Actually, I can't remember anything

glad to her that
Title: Re: Speedometer doing weird things
Post by: Wallington on February 17, 2019, 07:00:45 AM
Used speedos are everywhere if needed to test the setup cheaply to prove it works normally prior to new unit. Maybe you did that with older speedo.
Title: Re: Speedometer doing weird things
Post by: Crisis on April 26, 2019, 02:42:30 PM
Hello,

Finaly, ClassicIndustries has tested all his OER firebird 70-81 speedos that he has and they are all wrong.
So, Classic has done a refund and returned a check to me. Very kind, two years after bought this product !
I've ordered an used speedo on ebay and switched the face plate of the used by the one of the wrong new.

All good now. =D
Title: Re: Speedometer doing weird things
Post by: Nexus on May 23, 2019, 10:08:05 PM
AHH...right on...glad you found a solution
Title: Re: Speedometer doing weird things
Post by: Wallington on May 23, 2019, 10:43:26 PM
What in particular is wrong with the new units, as in what tests did he do to determine it's not just another customer complaining?!
Title: Re: Speedometer doing weird things
Post by: Crisis on May 30, 2019, 11:39:18 AM
Classic has tested one speedo before sending it to me. But it was wrong as mine.
Then, Classic has tested the next speedo, and the next, and the next, discovering that all his stock was wrong. Bad product serie from OER.
Title: Re: Speedometer doing weird things
Post by: b_hill_86 on May 30, 2019, 09:07:00 PM
Sheesh. Bad product, good info for others out there though. I wonder what the problem/solution is. I think I can hear the price of originals increasing...
Title: Re: Speedometer doing weird things
Post by: Wallington on May 30, 2019, 11:34:33 PM
There's a hell of a lot of them out there with no known issues or fault. Not sure they changed supplier for a spring or two or had a bad batch, that could happen to any if there's no testing during production to maintain quality control.