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Temp guage not working

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Baz

Baz

Yoda
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Pehaps I should rephrase that, the temp guage reads nothing. It is a dual guage with the oil pressure so I assume the guage has juice as the oild pres works. I suspect that the temperature bulb is bad.
The Hayens manual suggests I should change it to an electric model, but doesn't expand on that. Will a regular transmitter be alright?
It's a 1275.
Cheers.
 
Dual gauges are great. however the two systems (temp and oil) are separate. no juice is needed other than gauge illumination. the temp side of the gauge is not a wire, it is a tube, it must not be cut, broken, kinked, bent, or other wise compromised in anyway. If you convert to an electric one, you will only have a single guage for temp. i dont believe that duals come with an electric temp side?? the sending units will interchange, i believe. i converted my 1500 to a dual guage and all i needed was the adapter off a 1275 so i dont see why you couldnt go the other way, others may know better than i about this. If it was me i would purchase a new dual, or send it out and get it repaired.

mark
 
Much much cheeper to buy a new one than have it repaired or restored.
 
If the temp gauge (not guage) is not working, then the capillary tube is probably broken. I found a replacement for mine on eBay since it was dead when I got the car. I believe Moss has replacements too. If you do get a new one, just be careful threading the tube through the dash and firewall.
 
Looking at the prices of complete units, I understand they are full of mercury, I may be getting an electrical conversion instead. If that is the case, will I have to lose my dual guage, or can I get the electrical in the existing?
My brain was either wired by Lucas or I can't think in 1974eese.
Does the non-reading guage affect the thermostat in any way?
Sorry for mass of questions but it's been in the 90's here, lovely driving weather, but have this nagging concern about the engine temp.
 
It is two seperate gages in one housing, neither effects the other. No don't think it is mercury, escapes my mind but is a pita to change the tube and best left to an expert.

The whole unit must be replaced or rebuilt.

The oil pressure side has a tube and hose connection to the rear right side of engine where is connects directly to an oil access port. I really works on oil pressure.

Thermostat is only effected by water temp.

A cheep fix is a SW temp gage, electrical stuck under the dash if you have one. However, a real replacement unit will make you much happier I should think.
 
Baz, there is no mercury in the gauge. The capillary tubes are filled with a liquid, such as ether, that turns to gas at a fixed rate corresponding to the temperature. This gas pressure acts on a coiled tube, (Bourdon tube) in the gauge, that moves the needle through a small set of gears.
The non functioning gauge will in no way affect the cooling system. You just won't have any indication of how hot it really is.
I don't know of anyone that is offering an electric dual gauge. I'm not saying they aren't out there, just that I'm unaware of one.
If you want to convert to electric, you will have to run a separate temp gauge, and keep the existing oil pressure side of your dual gauge.
Jeff
 
Wow Jeff, same answer. Works for me, heh.
 
Thank you gentlemen, That link was very useful, looks like a new unit. Appreciate the insight.
Hmm, diapers for the baby or a new guage?
 
Cheers jack, that place looks a winner.
This is reason a B owner told me to join this forum, knowledgeable people with a desire to help.
 
And keep in mind what I said earlier, cheeper to buy a new one that rebuild the old. And I spoke with them.
 
[ QUOTE ]
Wow Jeff, same answer. Works for me, heh.

[/ QUOTE ]

Jack, I must have been typing mine while you were posting yours. I didn't see it until just now. Honest! /ubbthreads/images/graemlins/grin.gif
Jeff
 
OK, so you're dual gauge is dead. As Jeff said, the fluid that has escaped is ether. As others have said, it cost way more to recondition and recalibrate the gauge than NOS ones cost. Restoration is typically reserved for unique versions of the dual gauge because of the expense. That said, use the search feature here (and on Google) for repairing mechanical temperature gauges.

I'm not sure... but it could have been here in the Spridget forum that I first saw info on how to repair/rebuild these yourself. Like an idiot, I had thrown out all my dead dual gauges after learning how much they cost to fix. When I found the info on rebuilding them I got a friend to let me repair his gauge. It can be done following the info you'll find on this site and using Google. It's a delicate repair requiring a bit of care, but what have you got to loose? Assuming you have basic tools, the process will cost you a $20 donor gauge and a couple of bucks for ice and rock salt (not to mention your time). You'll have tremendous pride in fixing this yourself.

EDIT: Ooops! I meant to put in beg. If you decide you want to replace this gauge rather than rebuild it (professionally or DIY)... DON'T throw it out. Remember me and send it to me. I need to practice the repair on more than one gauge and need a dual gauge for my collection.
 
Doug, I'll dig around and see what I have lying around. I'm almost positive I have at least one.
Not to mention a brand new Autometer 2 5/8" liquid filled water temp gauge that got broken. But, Autometer only wants $37.00 to fix that one.
Jeff
 
A while back, I say new dual gauges, made in England, sellin on eby for roughly $75. Seemed like a good deal.
 
I did order a new one last night, my skills are not honed enough to attempt a repair. After the new one arrives, I'll see how badly I mess up the installation, if it's good, I'll let you have it, I'll keep in touch.
Please keep looking though because I will probably get myself into trouble and posting questions about what I have done wrong!
 
Thanks to all. Like I said, I've only done the repair once. When I tried to generate a full calibration curve on that gauge I found I had to spend a fair amount of time tweaking the bourdon tube linkage to make it read correctly between 120 and 212 degrees.

I found the link to the site that discusses repair of capillary tube gauges. Those who are interested take a look at:
https://www.ply33.com/Repair/tempgauge
The process does work and can be done with modest tools if you're careful.

Like Morris, I've seen NOS dual gauges sell for as little as $75 on eBay but the price flucuates according to what the gauge's specific application is/was. There were different versions that were car model specific. I've also seen a fair number with eBay "Buy it Now" prices around $130.
 
Doug, I'll send you a PM with news if the new one is OK, and address and then if you can snail mail me a shipping label, it's all yours. The oil pres works fine.
 
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