Today the ether came in. I tried to see if the old capillary is good but I think it is closed. I can not find a dent and I inserted a 0.1 MM wolfram wire about 4" into each side. So maybe it is open. I based it on ether coming out of the gauge when I unsoldered it and concluded that it was charged but the gauge did not respond..
So from the junkyard I had liberated a working temperature gauge. It had a small kink but was operational.
The capillary material is different.. The original is very thin and springy... Like phosphor bronze.. The junkyard one seems soft copper.
I cut the working one at the kink and smelled the ether as well. The temp. range of this gauge is higher.
I exercised my soldering skills without closing the capillary up and test the pressure of the gauge . with 10 bar it reads 260F .it should have read 248F to be compatible . this all might have been my tolerances and it being a cheap gauge that overestimates.
So after this promising beginning I soldered the original unimog gauge with the proven bulb of the other gauge.
I added 1cc of ether thru the capillary with a seringe while cooling the bulb down with ice water as to reduce the pressure . this seemed to work. Then with the bulb in the ice water I soldered the capillary onto the gauge.
Gauge responded on temp increase and I thought that I had a winner ...but then then a leak appeared at the gauge itself. So I disconnected the capillary again and found that the gauge had a hole drilled at the base. I guess someone else had tried the same thing before me.
I closed the hole. Confirmed the gauge was working.. Confirmed the capillary was open. Refilled again with same method. Resolderd and... Poor response. Gauge moved but not good.. So what is wrong? Not enough ether.. Contamination??
Tomorrow I will experiment some more.
So above the junkyard gauge that i used to hone my soldering skills on. At the same time I was able to measure the pressure rating on the gauge because i could hook it up with the 1/8 NPT adapter.
A little frustrated right now, this does not appear to be rocket science although the ether burning of gives it a certain rocket perspective.
tbc
Johan