[alsalp]

Originally Posted by Peter Serio

"I noticed that when I tried to use the harness or even having just the circuit board attached "the other two" would get "excited" when test a given gauge. What does this mean? The circuit board checks out. Using TU5, 185 deg is between the first two marks. 200 deg is at 1/4 mark, and My propane burner maxed at 206 with reading about in the middle of 1/4 and 1/2 marks."

I was not there right beside you when you were doing these tests but I think I know what you are saying. All 3 gauges in the #1 circle opening share a common power supply (key on) thru a 15 amp fuse. And all 3 share a common "reference" ground at the rear steel panel that they are bolted into. However each gauge seeks more information than just those 2 connections. Powering up gauges with a open sensor string can damage that gauge. Both the oil pressure and the fuel gauge in particular. There is no car condition ever that either of those two gauges would see infinity, it's as if their sensor wire was un-plugged. Making tests running 12 volts battery + thru the printed circuit as power MUST include completed sender strings for all 3 gauges. Otherwise you can damage a gauge. A string (1 each per gauge) would be your variable resistance box terminating to ground. That is why I have a total of 3 separate decade resistance boxes on top of my workbench.

So if I create a common ground through the shell and the CB I need the "other two" getting simulated or sender resistance while test a given gauge?

[Peter Serio]

Yes, if not it drives the pointer to an attitude which the gauge would never see during normal operation. By electricity power turned into magnetism the gauges can move their pointer further that your "view window" however that is undesirable especially when working on something 50 years old or older and is in failure mode anyway. There is a normal "sweep" to each gauge, and that includes what is indicated by those thin white lines. Anything beyond that is bad, with one exception.

And that would be for the temperature gauge; the topmost line which just says "C" everybody knows that stands for cold. Your normal start position is that line but I have seen many temp gauges (68 & '69-70) where the start position (cold engine) is slightly above that line which, in my opinion is totally normal. The top line or just above that line. Once set into motion by rising coolant temperature; that is where the other lines need to be right on the money!

[Carousel72TRed]

Hi Peter

You have been recommended by OG68 and will send you my gauges next year. I have a 69 GTO and there is a 140 mph speedo Rally Gauge cluster in it which narrows my cluster down to a 69-71 Grand Prix or 70-71 GTO. I also have a 68 Rally Gauge cluster, temp indication no 100-250 just graduated. Will the 68 cluster work in my 69 GTO once I get it refurbished. Both clusters temp. indications are faulty (not showing needle not there.). Also I am looking at finding a 69 GTO in dash tach (currently clock in it and not working) and I have a Summit HEI ignition in the car and the conversion kits Ames offers do not offer one for a 69 and same for their reproductions. Also when my cluster is lit the faceplate has a slight greenish tinge to it. Any information you could provide me would be appreciated. Please leave my your website address for future reference.

Thank You
Carousel72TRed

[4zpeed]

Originally Posted by Carousel72TRed

Hi Peter

You have been recommended by OG68 and will send you my gauges next year. I have a 69 GTO and there is a 140 mph speedo Rally Gauge cluster in it which narrows my cluster down to a 69-71 Grand Prix or 70-71 GTO. I also have a 68 Rally Gauge cluster, temp indication no 100-250 just graduated. Will the 68 cluster work in my 69 GTO once I get it refurbished. Both clusters temp. indications are faulty (not showing needle not there.). Also I am looking at finding a 69 GTO in dash tach (currently clock in it and not working) and I have a Summit HEI ignition in the car and the conversion kits Ames offers do not offer one for a 69 and same for their reproductions. Also when my cluster is lit the faceplate has a slight greenish tinge to it. Any information you could provide me would be appreciated. Please leave my your website address for future reference.

Thank You
Carousel72TRed

I am the member who actually recommended Peter and also added 3 links to threads with info and posts by Peter.

That said I have not spoken with Peter but if you would like to correspond with him you can 'Private Message' him.

To do that, click on Peter's name, a drop down box will appear, select Send a private message to Peter Serio.

To look at private messages or access other functions scroll to the top of the page and click "User CP".

I'm not sure how often Peter logs in to the forum but he will most likely respond to a private message.



Hope this helps,
Frank

[webfoot]

Originally Posted by Carousel72TRed

Please leave my your website address for future reference.

Thank You
Carousel72TRed

I don't think I've seen Pete post here in a while but here is his website, so you might not wait for him to see your post.
http://precisionpontiac.net/

He restored my rally gauges and converted my tach to run on an HEI.