The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - The resident newbie idiot needs to hook up a tach..

**ChiefRocka** · 11-07-2006, 10:26 AM

Well...lets see if we can help you out. As far as the gas guage goes...The fuel tank has a ground wire that goes from the sending unit to the body of the truck, below the window. The sender is grounded this due to the fact that the tank has insulaters on its straps, the gasket under the sender, and the rubber fuel fill at the neck. Make sure this wire is intact, and correctly grounded. Next check the wire that leaves the sender and runs across the tank, along the door sill, and up to the guage cluster. That might of gotten pinced, or cut when you were working the seats in and out. If you ground this wire to the truck metal, the guage will move to full. This will check the guage circuit is ok.

Now you have a battery draw ?? Does everything else related to column work (signals,horn). Did you mess with any other wires under the dash, or in the column ?? The battery is good, right ? I know this sounds dumb, but sometimes two things go wrong a the same time. Disconnect your battery ground wire...connect a test light between the (-) post and the (-) cable...leave it there. When theirs a draw, the light will light. Now you can check the wires and find out where the draw is. If you find the problem, the light will go out. Make sure you don't have any shorts, alt. being energized with the key off, etc. Also, if you have a radio with a memory wire, temporaly disconnect that, because that will "light" the test light as well.

Now as far as the tack goes. Usally the "green" wire hooks to the (-) side of your ignition coil...to the "tack" terminal of an HEI dist...or to the (gray) wire (I believe) of an MSD box. Not sure what you are running. Then you should have a ground wire (obvious), a power wire that should be fused and hooked to a 12v source with key on circuit, and finally the tach should have a light for the face. This usually is hooked up the headlight switch, the dimmer/dash light output. Alot of guys hook this wire to the 12v power to simplify installation. The tack will light when the truck is on. Not to big of a deal, but I prefer it to be dimmed as well.

Well I hope this wil help you out.....Let me know I can help...

John

11-07-2006, 10:26 AM	#2
ChiefRocka Hollister, CA. Join Date: Sep 2006 Location: Hollister, Ca. Posts: 6,151	Re: The resident newbie idiot needs to hook up a tach.. Well...lets see if we can help you out. As far as the gas guage goes...The fuel tank has a ground wire that goes from the sending unit to the body of the truck, below the window. The sender is grounded this due to the fact that the tank has insulaters on its straps, the gasket under the sender, and the rubber fuel fill at the neck. Make sure this wire is intact, and correctly grounded. Next check the wire that leaves the sender and runs across the tank, along the door sill, and up to the guage cluster. That might of gotten pinced, or cut when you were working the seats in and out. If you ground this wire to the truck metal, the guage will move to full. This will check the guage circuit is ok. Now you have a battery draw ?? Does everything else related to column work (signals,horn). Did you mess with any other wires under the dash, or in the column ?? The battery is good, right ? I know this sounds dumb, but sometimes two things go wrong a the same time. Disconnect your battery ground wire...connect a test light between the (-) post and the (-) cable...leave it there. When theirs a draw, the light will light. Now you can check the wires and find out where the draw is. If you find the problem, the light will go out. Make sure you don't have any shorts, alt. being energized with the key off, etc. Also, if you have a radio with a memory wire, temporaly disconnect that, because that will "light" the test light as well. Now as far as the tack goes. Usally the "green" wire hooks to the (-) side of your ignition coil...to the "tack" terminal of an HEI dist...or to the (gray) wire (I believe) of an MSD box. Not sure what you are running. Then you should have a ground wire (obvious), a power wire that should be fused and hooked to a 12v source with key on circuit, and finally the tach should have a light for the face. This usually is hooked up the headlight switch, the dimmer/dash light output. Alot of guys hook this wire to the 12v power to simplify installation. The tack will light when the truck is on. Not to big of a deal, but I prefer it to be dimmed as well. Well I hope this wil help you out.....Let me know I can help... John __________________ John What the Heck is that ?? CURRENT BUILDS: 62 BurbMaster Other Builds: My '63 C-10,LWB,CC,BBW '06 HD StrAight Axle Swap Father/Son '67 C-20, LQ9,4L80,Bagged,8-Lugger !!Good Friend Richard's Build AMERICAN CUSTOMS & CLASSICS (831) 630-1965 www.ACCHOLLISTER.com ACC on FACEBOOK "Rest in Peace, Mom & Dad ... I will see you again someday!" Last edited by ChiefRocka; 11-07-2006 at 10:30 AM.