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MG MGB Technical - More questions??

Well now it's time to get the guages working.
The speedometer doesn't work because there is no cable, that's the easy one.
The tach doesn't work. Everything seems to be hooked up properly, as best I can tell. I read through the electrical portion on the site dealing with the tach, but it's mostly Greek to me.
The oil and temp work, but I don't know if I trust them. The oil pressure is pretty steady around 60lbs.
and the water temp hovers around 100 deg. F, but it's boiling over once and a while. Usually while sitting for a bit and temp gets up to 120 deg. F. I though water boiled at 212 F.??????????
Are there some physics I'm missing? Radiator cap is 7lbs.
Jordan

Yes. Your gauge reads in degrees Centigrade! Water boils at 100C, but with antifreeze the boiling point is higher, depending on concentration. Investigate and repair as soon as possible.
Andrew Blackley

That's what I thought, but I had to look at the guage again, and it says "Water degrees F" Is this coincidence or what?
Jordan

Jordan - If the coolant in your car is boiling, then the temperature is at 212° F or 100° C. One way or the other your temp gauge is lying to you. Normally, the temp gauges int he MGBs registered in degrees F, but yours may have an odd ball gauge. Get a candy thermometer and plade it in the filler neck of the radiator and compare readings with the temperature gauge. The next problem is to find out why the car is running so hot. This could be anything from a stuck thermostat to a glogged radiator or clogged cooling passages in the engine or head or it could be a blown head gasket (although a blown head gasket ususally manifests itself in other ways also - like a lot of noise). Start with the easy and cheap things first by swapping out the thermostat. While the thermostat is out try running some radiator flush through the system and then back flush the system. If this fails, then have the radiator recored. Make sure that the shop recores with a 4 row L type core. If you can't find a shop that can do that, contact me at my e-mail address above and I can put you together with someone who can. The tach problem may be a bad power connection, a bad ground, the sensor wire not hooked up correctly or the tach may just have died. Good luck - Dave
David DuBois

Sorry Jordan. I re-read your other posts. Your car is a 67? Then the gauge should be reading in Fahrenheit. If the readings are low and the car overheats, then the combination gauge is bad. Not uncommon. Follow Dave's advice above. Also check for timing too far advanced.
Cheers, Andy
Andrew Blackley

This thread was discussed on 04/06/2002

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