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Temperature Gauge

chuggy

Freshman Member
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Hi there, I have a 66 MGB which I recently aquired. The water gauge has never worked and obviously want to get it working
The fuel gauage and oil gauge are fine.
Any help would be appreciated.
 
If it's the original dual gauge (oil pressure/water temp) it's likely in need of rebuilding, as it is an ether bulb sender. It can get expensive. Which island are you on (north or south)?
 
I'm in the north island.
It is the dual gauge type. Do you check the gauge and capillary tube by substitution.
 
Who's the good guage rebuilder? I've been recommended Palo Alto (or something like that).
 
Nisonger is THE place... kinda like Curto for SU rebuilds.

Chuggy: There's no easy way to "check" it. If the water temp is not reading, chances are the capillary tube has been damaged (ruptured) somewhere along it's length. If you want it to be as original it'll need a new bulb/tube and calibration. Not sure who I'd suggest in your part of the planet, and my only contact is on the south island. Omaru, actually. I'll check to see if there's a good service near you.
 
How 'bout for Alfa's Doc? I gotta send off my tach.
 
I pressume the gauge just connects to the tube then into the block just below the thermostat. Is it an easy swap?
thanks for all your help
 
My water guage on my MGB is electrical. is it mechanical on the early ones? The only guage I have with a tube is the oil pressure one.
 
yep its mechanical. I pressure you can just change the gauge see if that rectifys the problem. If not then just change the tube?
 
It's a sealed unit from the factory, and now "unobtanium" so treat it with respect. It needs to be "threaded" thru the dash opening, the bulkhead and routed to the bung-hole under the thermostat housing, yes. It's all-of-a piece. The pressure line from the oil galley to the instrument is removeable at the back of the gauge, the temp sensor is a permanent part of the instrument.
 
OH!! And welcome to the forum!! Hope you stay around: We don't have enuff Kiwi's in here!!! /ubbthreads/images/graemlins/jester.gif /ubbthreads/images/graemlins/thumbsup.gif
 
Yes Welcome!
 
so looks like I may have to buy a complete new unit!
thanks for all that. Im actually bristish now living here in Kiwi land!
All new to the world of the MGB, recently got the car running and looking forward to using it over the summer before I start ripping it apart!
 
Chuggy - John Marks in England is perhaps as good a place for you to send your gauge/capaliary tube/sensor bulb as any. I believe that the name of his business is Vintage Restorations, but I'm not sure. He has adverts on the MGCC web site at: https://www.mgcars.org.uk/mgcc/cc01a.html and on the MG Cars Enthusiast Club web site at: https://www.mgcars.org.uk/index.html
Good luck,
 
Chuggy - welcome from a fellow NZ-er!
 
The temperature gauges are a DIY repair. I ran across this repair procedure and used it to repair the temp gauge on my TR3. You need a working donor capillary gauge for the tube and ether bulb, but I've seen those in auto parts stores for a little as $16.

/ubbthreads/images/graemlins/cheers.gif
 
To the best of my knowledge, all Smiths dual gauges have always been purely mechanical. By all means, test your existing gauge as suggested above before investing anything.

There are routinely NOS dual gauges on eBay with "Buy It Now" for around $130. True auctions frequently go for less. When I checked with Palo Alto and Nisonger about two years ago, the cost of reconditioning an original dual gauge exceeded $140... so it was only justified when the instrument was rare and the NOS stuff didn't match.

The link above for the DIY repair is good. I've repaired a gauge using the procedure. There is a little skill involved, but there is nothing there that most DIY LBC mechanics couldn't handle. It won't cost you more than the donor gauge and a few dollars for supplies to give it a try. You aren't going to make the gauge any worse if you fail.
 
These are pricey new. The $140USD figure for a dual gauge is pretty much on the mark. You can get them from both CAI Gauge and Holden.

This likely isn't a viable option for Chuggy, but suppose one wanted to change the older, manual gauge for one with the electrical sending unit? (Or the other way around, for that matter.) Are the threads on the sending units interchangeable?

R.
 
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