For my '70 GS455: need to know specifically what size brass "T" addapter to purchase at a home improvement store for the oil pressure sender which I plan to mate under sender. What size gauge wire do I need for the volts gauge and will it go to + connector at rear of alternator? Thirdly, for the water temp sender, I'm planning to mount and mate it where the thervac switch is on top of factory intake. (removing themovac altogether) What will I need there as to plumbing the water temp sender? I do have the copper line kit from NAPA for the oil pressure line. Gauges are mechanical I believe and it is a Sumit triple gauge cluster. I'm also wanting to retain all factory idiot light capability. Any and all help appreciated as well as any tips shared. Thanks!
Hi Evans, First...if that NAPA kit has a plastic coiled line in it, ditch it! That line will get you in trouble every time, it's just a matter of time. And believe me, when I was a young teen with my first '72 GS455 I went that route and one day the front carpet got soaked with oil when it blew!!ou: I really would recommend a -04AN braided line and fittings as my number one choice but after that you should at least use 1/8" copper tubing. It will substitute the plastic line without needing anything else. But be careful when routing it as you can bend it back and forth too much without it fracturing on you. The brass fitting you need for the side of the block is a 1/4"NPT male with 1/8"NPT female inside. From there a brass threaded pipe about 2" in overall length to a 3-way brass junction, all female threaded 1/8"NPT. One end (of course) for the pipe that comes from the block, and the other two for the new mech. line and the stock sending unit. You will need a brass adapter (reducer) that has 1/8"NPT male and 1/4"NPT female. This will allow you the luxury ( :Brow: ) of using the stock idiot light. I would use no smaller than 14gauge wire for your volts gauge. You can actually just run it to a "key only" HOT at the fuse box. Do you already have the gauge set? I ask because the water temp adapter usually comes with the proper 1/2"NPT male fitting. It does have a special female thread for the coupler that is needed. You will not find this piece at your local hardware store however. A local speed shop should be able to get you one though if you do indeed need it..... Hope this helps..... :TU:
Ditto on the braided line for the oil guage..... I have a $140 pair of dress shoes that are totally oil soaked from the plastic POS line failing......If you want proof I'll send them to ya Took over 2 years to fail....but it WILL Kerry didn't mention this but....you'll need to drill at least one hole through your firewall to snake all the stuff through. You'll also then want to use good rubbber grommet to insulate the stuff from the rough edges of the hole in the firewall. It may take alittle extra time, but I'd suggest doing a Mock-Up of the hole in a piece of scrap tin to determine the smallest hole you can snake all the lines and sending unit through.....then buy a grommet to fit this size hole (take the mock-up with you to the grommet store:laugh: ) You may need to add alittle to the size because of the space the grommet will take up..... Then mark the area you've chosen on the firewall with a circle using a grease pencil. MAKE SURE there is nothing on the inside blocking your location BEFORE you start making the hole. You'll also have to pull back the carpet and insulation a bit. Drill the initial hole with a drill bit large enough to fit a Dremel Grinding stone inside of, then use the dremel to widen the hole to the circle marked by the grease pencil. Go Slowly ..... INSTALL THE GROMMET !!!
I didn't need to drill a single hole when installing my gauges... went right thru the large grommet right behind the carb along the firewall I didn't even cut into that grommet either. its the same grommet where the rubber vacuum line goes into the car for the heating system (I think) I ran the sending unit for my mechanical water temp gauge and copper line for my oil thru this opening Nate
thanks everyone! I appreciate all the tips guys and the size adapters needed for this. Triple gauges were given to me by a friend and don't have all the parts- these got lost thru the years.... know how that goes. The NAPA line kit I bought is the copper tubing one so it's not the plastic set up. The triple gauge oil press does have the cheesey plastic line still on and you can tell it's been used. Looks like a trip to Lowes or Home Depot is in order for adapters and grommet. Thanks again!
The hole in the firewall will be 7/8 inch according to the directions in my Autometer set.Sounds big,but the nut on the capillary tube is that size.Thats why I like the electric water temp gauges. Pat
You will need what is called a 1/4 pipe thread street "T" for your oil pressure gauge, this will allow you to still retain the idiot ligth as well. The wire size for the volt meter is not critical, it is measuring volts only and not amps, a small wire here is fine, . You want to hook it to a switched 12 volt source on the fuse box, not directly to the alternator. Taking the switch out of the intake mainfold is all you need to do, your gauge kit will have the proper adapters already for the hook-up to the mainfold. Jim Burek P.A.E. ENTERPRISES
thanks Jim! Thank you Jim. Your expalnation gives even better clarity to the situation at hand. Sure hope Lowe's or HD will have these fittings? Would a switched 12v ign source for the volts, be at the ign terminal at fuse box? Do I also need to use any teflon tape or plumber's tape when at fitting for "T's"?
Re: thanks Jim! The ignition terminal on the fuse box will be firne. Most auto parts stores will also have the fitting you need. You can either use teflon tape or pipe joint compound, White teflon paste for the fittings. Jim Burek
oops... it's an amp gauge instead of volts gauge in cluster Just noticed that the gauge I thought that was a volts gauge is actually an amps gauge. Would the two connections on back go to 12v positive terminal at battery and the other to positive rear of alternator? Someone please confirm or enlighten me. I'm also alittle stumped on how to wire this triple cluster for lighting. I'm planning on tapping into clock wire under dash since I don't have an in-dash clock so I can have lights on only with lights in on position and also have ability to dim. My question concerns where and how to connect at rear of triple cluster so I'll get lights to all??? o No:
Evans, The lighting is very easy. There should be 2 leads for each light, a hot lead (white) and a ground(black). Wire all the hot leads together and connect them to the ashtray light(much easier to get to). Then wire all the grounds together and attach to a metal portion of the dash. An ammeter wires differently than a voltmeter. I believe it has to go series with the main alternator feed. Not sure on this.
Hey thanks Larry! So, would it matter which of the two terminals on back of each gauge I used for hot/ ground, as long as I sat consistent for all? Maybe someone will pipe in with proper wiring for the ammeter gauge. I have no instructions with this gift set from my friend. Also, on the water temp gauge, I plan to use the themovac port on intake and remove that. What size reducer/ brass fitting will I need to connect that? I know it's the same size as the heater nipple fitting into the intake manifold. I did manage to find all that I needed with the fittings for the oil temp sender to T and use factory idiot lights too between HD and Lowe's.
