Issues with a factory tach install???
 

Ok, heres the deal....I have read the various threads on here and the pther sites about this swap and thought that the clusters after '78 were a plug and play? I have an '83. I did the swap and completed the white face change. the tach works great, speedometer fine but the other gauges I got zippy!! The temp gauge pegs out either cold or hot during cranking and when turned off and while running does a complete 180 and sits in an area that does not read anything. Volts has not mover as of yet, oil pressure pegged out once and has not moved since and the fuel gauge has not moved at all. I'm sure this is an issue that is my fault, I ran a test light to the back of each gauge on the circuit board and they are all getting juice???? I am no electric/wiring guy by anymeans so I was looking for some insight from the vets....what are we thinking??? ground? wiring ??? etc...anything

Re: Issues with a factory tach install???
 

What year is the gauge cluster out of?
Did you ad the tach and move the fuel gauge on a non-tach cluster?
There are different printed circuits for each
I swapped the gauge cluster for the dummy light cluster on my old '69 and had to switch half the wires around in the plug after back tracing
Sounds like there is power to a ground circuit

Re: Issues with a factory tach install???
 

I dont have the exact date but I think its out of a '78 or later...my understanding was that these years were plug and play...I changed out the entire cluster...I checked the back of the circuit board and have juice running to all terminals just no accurate readings

Re: Issues with a factory tach install???
 

Based on your description the wiring harness you have incompatible cluster circuit to your existing dash harness. IMHO, plug and play assumes that components in hand are known. This might be not the case, as it is very easy to swap instrument flex circuit and most would not be able to tell the difference.
You need to determine the following:
1) Remove cluster, and carefully map out all the wires going to the plug (note locations and color of wires). Function of each wire can be looked up from FSM.
2) Trace out all circuit traces on the flex circuit. Also note flex circuit part number. Now, you'll be able establish what is wrong - plug to circuit to instrument.

There are over a dozen different flex circuits that can be fitted on the back of your cluster, but only one (maybe two) will work correctly.

//RF

Re: Issues with a factory tach install???
 

It is plug an play in the sense that it is all electronic, not you plug it in and it works. You still need to repin the actual connector. If you had dummy lights before, none of the senders will work either.

Re: Issues with a factory tach install???
 

Yea I was feeling that I would have to re-pin the connector...I had already changed the senders to gauge types...I suppose I will do a search on here to try and find a thread where someone has re-pinned one before...I think I recall a write up on the 73-87.com?? Again I would say I'm far from stupid but this type of stuff really makes me scratch my head

Re: Issues with a factory tach install???
 

where did u buy it at?

Re: Issues with a factory tach install???
 

The gauges and sending units can be fragile when shorted
Hopefully everything is ok
I ended up drawing a schematic for the old cluster and new to keep it straight
That was for a 1969 so not going to help your dilemma
I was interested in where/how much for the white faces?
Please let me know -I'm always looking for a deal
Thanks

Re: Issues with a factory tach install???
 

Got the cluster from Carlisle, PA flea market/car show a couple years back

Re: Issues with a factory tach install???
 

I purchased these over lays a couple years ago from a guy on ebay...here is a link

http://cgi.ebay.com/ebaymotors/1980-...Q5fAccessories

looks to be around $24-25...these actually look a lil better then the ones I purchased back then....I had to cut out the windows for the odometer, light and all...looks like he may be improving in his R&D :lol:

Re: Issues with a factory tach install???
 

Thanks for the link!
Looks to be a fairly good kit -wonder how it will age?
I actually need to swap a tach cluster from my '78 burb to my '77 GMC
I have an early 80's maybe '84 tach cluster but the font didn't match and I knew there would be quite a bit of "custom" work to get the wiring right
At least I have both trucks to figure it out
Not sure how much help I can be without an 80's truck in front of me
Thanks again and good luck -It can be done

Re: Issues with a factory tach install???
 

not sure how they last installed....hoping they are good for a few years atleast...I know the swap can be done...just gonna take a lil patience and some time on my behalf...probably get started on it next week...thanks for the words of encouragement :lol:...lemme know what ya come with if you pull the trigger on those gauge faces