100-4 dual gauge

Anyone use an original oil pressure / water temp gauge with a Chevy 350? Will the oil pressure line screw on and work with no modifications? I'm currently using a Stewart Warner oil pressure gauge but would like to get a dual gauge installed. I still have the boss on the radiator for the water temp sender.

Should be no reason it would not work. Both portions of the gauge are mechanical and will work on any engine with the correct adapter fittings.

For oil pressure use the straight hose fitting here: https://www.pegasusautoracing.com/productselection.asp?Product=3268 with a -3 hose connected to an appropriate fitting on the motor end.

Thanks HealeyRick! The straight fitting in the link is 2 fittings screwed together correct? (the actual fitting and a hose end that screws of?) I'm just a little confused if I can connect the oil pressure line that is already installed on the SW gauge once I get the fitting and dual gauge installed.

The fitting is a single unit that comes apart to allow you to install the hose. I don't know what the SW end is like so can't be of any help there., but in order to use this fitting you'll have to use the teflon hose along with a fitting that will work with the Chevy block.

Isn't the SW oil line 1/8" diameter copper tubing? If so, the easiest path is to buy a new copper oil pressure gauge line kit. Many retailers carry them. One of the fittings in the kit will be a female 1/8 NPT to 1/8" tube compression fitting. The gauge will NOT have 1/8 NPT on its back but a straight 1/8" pipe thread. Therefore, put a couple of wraps of Teflon tape on the male gauge threads, then screw the female compression fitting onto the gauge. Your old SW line probably will screw right onto the new compression fitting. However, if it doesn't... you have new tubing in the kit.

The temperature gauge should fit. MOST of the aftermarket mechanical temperature gauges use a 5/8-18 thread for the nut that secures the gauge's expansion bulb. In a few instances the block may have 3/8" pipe threads. You won't know until you remove the old expansion bulb from the engine if an adapter will be needed to use the dual gauge. That being said, if you currently have a SW temperature gauge, it should use the same threads as the dual gauge.

dklawson, I received my dual gauge and plan on installing it in a week or so. Is there a particular kit you recommend for the fitting?

Hi. It depends on what you want and what your local parts store has.

For a quick and easy installation your local parts store may/should have a copper line kit. Since the dual gauge will have straight pipe threads on it, expect to use Teflon tape on the gauge threads to seal it to the copper tube adapter fitting. You will not be able to use the flat sealing washer used on Smiths and Jaeger gauges. Run the copper line from the passenger compartment into the engine bay. At a convenient location in the engine bay, wrap/loop the copper tubing around a small can/cylinder/bottle perhaps 1-1/2 to 2" in diameter making a coil with 3 or 4 loops. The coil will become a storage loop to absorb engine vibration. That will extend the fatigue life of the tubing. The copper kits are typically $10 to $15. You can see the contents of Dorman copper line kit #7-147 in the link below.
https://www.amazon.com/Dorman-7-147-Gauge-Install-Kit/dp/B0024GQ7D2

If you want a nicer and more permanent solution (for a little more money) consider ordering a braided oil line kit like that shown above in HealyRick's post. These typically sell for around $30 if you order online from a supplier like Summit or Jegs. These kits are heavier duty and should not be subject to fatigue. I'm posting a link to one such kit, other lengths are available. Summit also sells similar kits by Longacre. To select the right length, run a heavy string from the gauge along the path to the pressure port on the engine. Measure that string to determine the closest length kit available.
https://www.summitracing.com/parts/aaf-all46110-60

I like the braided oil line kits if you don't mind spending a little more. Look carefully at the contents of the kit. As shown in the link I posted above, make sure the kit includes a male fitting with male threads you can screw into the engine block and a male fitting with female pipe threads for the back of the gauge. You want the hose itself to have female fittings on each end so during engine or dash service you can easily unscrew both/either end of the hose. Some hose kits will instead of a hose end with male pipe threads. Those are much harder to deal with.

Is this the correct kit? The link you sent above is unavailable.

Bosch SP0F000012 Copper Tubing Installation Kit https://www.amazon.com/dp/B00UZ9HC2U/ref=cm_sw_r_cp_api_AYC7Bb18TQD27

The Bosch kit can be the correct kit. The kits are made by several manufacturers. The picture in your product link looks like it has all the parts you will need.

I just pulled out the SW gauge, it had a fitting on it already. Doesn’t this look like what I need?? Of course I don’t have the dual gauge now, it’s at the shop that’s modifying my aluminum radiator.

Yes, but.... What you do not have (at least not shown in the picture) is the tubing itself, the compression ferule, and the ferule nut.

Am I missing something? Wouldn't it make more sense to order the correct parts from Moss?

I already have the line set up that is connected to the engine. This is a running car and I’m just replacing the SW gauge a previous owner installed. steveg this gauge is going to be connected to a Chevy 350, I wasn’t sure if this would be a simple replacement or if it will need adapters to be able for it to work.

I had some free time to install the gauge today, the adapter from the SW gauge worked with no issues. Thanks for all the info.

Went for a drive today, temperature and pressure indicated with no issues. The numbers matched the SW gauges I removed :eagerness:.

Matching readings are always comforting. I'm glad the gauge installed without problems and is working well.