I am just getting my 46 ford on the road here in not so sunny England and everything is good now as I have finally found my chassis numbers for registration purposes. All good that is except what my temp guage is reading when I drive it for more than 10 mins or so. After only 3 or 4 miles the temp guage is pretty much right to the top so before I start the process of dismantling things I want to know if anybody can tell me what the temps should be at the 3/4 and top marks on the guage. After idling for a while and then a blat round the block a reading from the rad was showing around 160 degrees and the guage showing a little over the 3/4 mark. I appear to be getting flow in the system ok as you can see fluid movement in the rad top whilst the engine is running. Anybody have any thoughts/experience of possibly faulty guages/senders etc??? I have read a few tech posts on here about cooling these but I'd like to be sure before I have to crack open my already unhealthy wallet again.
If it doesn't puke out the overflow, don't worry about it. No two of those gauges is going to read the same. If you have checked it with a thermometer as you said and it is only showing 160 you are in great shape. At full hot on the gauge, it probably is only 180 or so. Still very accepatable.
At 160 you aint even half hot yet. But seriously as long as the radiator is in top shape (you cant economise here on a flatty) and the 46 fan is in the correct position central to the core and the thermostats are opening and the temp isnt steadily rising i would stay a little more relaxed about it. I know when you own a flatty temp is always a concern but as long as it isnt rising to puke over and can hold its own ,its all good. Obviously you have a way of measuring temp other the the original gauge so dont panic and carefully monitor whats going on and get back to us. you can run a 7 pound cap on a 46.
This test will work for most stock Ford water temperature measuring systems. To test your temperature senders would require a hot plate and a pan of oil to suspend them in while checking actual temp with a regular thermometer. I use oil because it won't boil at lower temperatures like water. The senders don't care what the fluid is anyway. You will need a jumper lead to attach between the sender units and the temperature indicator wire in the vehicle depending on how far you are away from that vehicle. You'll have to remove both senders and the sender to sender wire to conduct the test. I ususlly use stainless safety wire to wrap around the senders to just suspend them in the oil and act as a ground connect with a jumper lead back to the car frame or battery positive (6-volt positive earth). The single post unit should be suspended in the oil first to get a climbing temperature reading. The double post sender will only give an open indication when you check it. It should go to full hot when it reaches near 206 degrees F (some are factory set for higher or lower temps and have a temp stamped on). If your double post sender is malfunctioning it will just go straight to hot at a lower temperature than 206 or a higher temperature than 206 or it won't open at all. This will give you some piece of mind about the indicator readings you are getting plus you will know approximately what temprature the water is at different indicator readings. A 4-lb radiator cap will delay the boiling point from 212 degrees a fair amount but I'm sure it will start to puke water somewhere near the 220 to 230 degree mark give or take a little.
I can see tomorrow will be a day of boiling oil and wires draped everywhere! Tests will occur and I shall post the results!
hi i would buy a stewart warner oil pressure and temp gauge, plus keep your orignal ones, just hang them under the dash . get mechanical ones. i have a 36 ford pickup and i put some in and my temp only gets about 140 when it is about 60 out side . i think the set of stewart warner gauges is cheap insurance don't rely on the factory ones, you don't wont to blow up your motor
Buy yourself a remote laser thermometer and see what the engine temp really is at various gauge readings. Mine is the handiest diagnostic tool I have. Find missing plugs, plugged rad cores, all sorts of uses.
Well a quick update for all who have been kind enough to pass on some very helpful info. After a bit of a delayed start I got testing the senders, who'd of thought it would be so difficult to get an accurate thermometer!!! I tried 3 different thermometers all of which had wildly varying results, one cooking dial type, one digital pyrometer kindly loaned from the maclaren F1 outfit (overread by up to 60 degrees!)and one laser number which read my body temp as I should be almost dead! Finally I laid my hands on a school style mercury number, the only one to read boiling water as 212 degrees. During the suggested test at 150 my dial was already reading over 3/4and was already at the top by 180. By the time the liquid got to 195 my gauge needle was all the way over to the ignition off position. I drove the old tub around for a little while to get the temp right up and each time the thermometer went into the rad top the max reading was a little under 180 or less. Conclusion being I am a little more relaxed about driving with a crazy gauge. Will definitely need to look into a seperate dial though. Thanks again to all for the info.
Those old gauges are adjustable somewhat - on the back there should be a thin bit of cardboard - peel this back and there should be two holes inside of which you can spot some tiny gears - these are the adjustments. Go VERY small and remeasure until you get the gauges where you want. A bit trying, but do-able....
I put a resister to ground on my single pole sender after reading the head temp at thr sender location with a laser gun. Increased current pulls the dash gauge pointer towards the cold position. I have a Word procedure I wrote about 7 years ago on how to size the resister. I could e-mail to you if you like. Jim
Hey Jim, I would be quite interested to read your write up on the resistor set up, could you email it to me a [email protected] .Tom.
Jim, I would also like to have a copy of your program if you don't mind. Thanks. Ron [email protected]
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