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dual gauge oil hook up...

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Nunyas

Nunyas

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Ok, I hate sounding like a 'neophyte', but I have questions and would like answers, mainly to make the installation of my newly acquired Smiths dual gauge go as smoothly as possible.

The gauge came with the lead and temp sensor for the coolant temp, and I reckon connecting it will be a straight forward process. However, on the oil pressure side it only has a threaded fitting.

I believe someone mentioned before that it's best to use 1/8" copper tubing to connect the oil press. gauge to the engine block. I believe acquiring the tubing ought to be easy enough, but what size fittings will I need to pick up in order to connect the tubing to the engine block and the back of the gauge? Also will I need to do any flaring to ensure a leak tight fit?

Thanks!
 
I don't remember the fitting size off hand, but I bet you can pick up the complete oil pressure tube from Moss. It will be at your door tomorrow, ready to screw on.
 
duuuuuhhh... I hadn't thought of that.... *smacks forehead*
 
Rob - there should be a solid pipe up under the dash that the oil guage hooks to...& then that pipe should run outside the firewall where you hook a flex line.
 
If I'm not mistaken, his car currently has an electric oil pressure sender. I may be wrong, as I don't know the later cars very well. But for $20 if might be worth replacing anyway if it's 30 years old. Definitely use a new flex line while it's apart. Yes it's just for a gauge, but if it breaks, it will let all the oil out of the engine.
 
Ah...didn't realize he had electric pickup.
 
'76 with stock gauges. Converting it to a Smiths dual oil/temp gauge. I assumed I have electric sending unit for the pressure and ordered my parts as if I were replacing ~everything~ between the engine block and the gauge on an older car.
 
'76 has a 'mechanical' sending unit....you should have a flex hose from the sending unit on the block to the firewall where there's a hard line to the back of the guage....that line might just hook directly to your thraded connection on the back of your guage

'68-'72 used the electrical sending unit (expensive) so you'll also need that unit along with the electrical wiring for it.

However, I just went out to look at the back of a round dual guage - its hard lined on the oil side for a 'mechanical' sending unit.....if that's the one you've got, your car is already hooked up for it.
 
I bought a dual mechanical gauge (round). The location of the stock oil gauge to the new dual gauge is about 6", I reckon. The stock gauge is between the tach and speedo. The new gauge will be going where the stock temp gauge was to the right of the speedo.

Well, I'll give it a whirl this weekend with the hardware already in there. I can tell this is gonna be fun poking around behind the dash...
 
Yep all MGBs have mechanical oil pressure hook up, all in the same place, passenger side of the motor just in front of the oil exit line on the back top side of the block.
 
Dave is correct that the block will be tapped 1/8 BSP. It's the same tap on my Mini and my Triumph. Though it shouldn't fit, a 1/8NPT male fitting with Teflon tape will fit and seal quite well. You can order specialized kits from places like Moss, or you can buy the generic kit from places like AutoZone or Advance Auto. If you opt for the local and generic parts, my advice is to go with the 1/8" copper tubing kits and skip the ones using Nylon tubing. Nylon will work but it age hardens over time and may surprise you with a big mess several years from now.

If you buy the generic kit from Advance or elsewhere, it will include male 1/8NPTx1/8Tube compression fittings for the block. There will also be a 1/8NPT-FemaleX1/8Tube compression fitting for the gauge. The Smiths gauge will have a 1/8BSP male thread which again... covered with Teflon tape this will seal to nicely with the NPT fitting.

Lastly, do not run the copper line straight from the gauge to the firewall. Find an out-of-the-way location between the block and the firewall along the path you'll route the line and form the tubing into a coil of several loops about 1.5-2" in diameter. These coils will absorb some of the engine's rocking motion and prolong the life of the tubing.
 
Rob - I'm curious....have you found your original oil pressure tubing behind the dash (its attached to the firewall) & can see how it runs across the firewall to exit over behind the glove box?

The only thing you're gonna need to do, I think, is figure out a way to extend it to your new guage location &, while you could use a flex line, be careful making connections behind the dash or you might end up with hot oil all over everything!
 
I wouldn't put anything rubber under the dash. For $20, get the new hard pipe and save yourself from future headaches.
 
/bcforum/images/%%GRAEMLIN_URL%%/iagree.gif The pre-made line from gauge to firewall fitting is the best bet. That makes it a one-CAB job. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
I recieved the new hard pipe, flex line, hard to soft connector, grommets and washer today. I've not had a chance to probe around behind the dash yet. I figure I'll do it on Sunday (I get to "pop" an Accord bumper on Sat), and then go for a test run in the mountains /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
You're set!
 
slapped that puppy in there today. didn't take long at all; probably around an hour or so. However, I'd like to smack the guy that decided to bolt the square oil pressure gauge in with 2 1/4" nuts. I had to pop out both the tach and speedo to remove that thing to gain access to the oil line. That was the worst part of the work.

I gotta say having the mechanical temp is really nice. It ~always~ tells me the temp of the car, and I can tell if I need to choke before I even switch the ignition on! /bcforum/images/%%GRAEMLIN_URL%%/grin.gif

The only complaint I can think of after this swap isn't really a big deal. It's the lighting in the dual gauge isn't the same as the lighting in the rest of my instruments. The dual gauge is more of an incandescent color while the rest of them are greenish. But that's no big deal really. That only shows at night. The rest of the time, that thing looks sweet in the dash, and performs wonderfully! /bcforum/images/%%GRAEMLIN_URL%%/grin.gif

Glad I put that thing in there!
 
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