Author Topic: Rare Sun Manometer -- refurbish  (Read 2146 times)

Offline goodfellow

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Rare Sun Manometer -- refurbish
« on: October 10, 2020, 11:55:48 AM »
Note: These threads are old. I managed to restore these Sun Automotive Equipment threads from backups that I had made several years ago.
Hope you like them -


I was surfing eBay when just by chance I stumbled across one of the most rare add-ons for older Sun distributor testers; a vintage Sun manometer. This is THE tool for checking the distributor vacuum advance on many early cars -- but most notably Lincoln, Mercury, and Ford. These distributors had such sensitive vacuum setting that only a laboratory quality vacuum scale could find the proper setting. The standard vacuum gauges on the Sun testers weren't nearly accurate enough to get the correct reading.

Problem is that most of these things were broken off early in the life. On the old Sun testers they stuck straight up out the back of the tester cabinet and were just begging to be hit by something. I've bid on these things before and always lost out because the prices went through the roof --often going over $400+. This manometer was inadvertently listed in the laboratory equipment section on ebay; so I guess the previous owner didn't know what instrument he had -- LUCKY FOR ME!!! I picked it up for less that $25.

This is how it arrived -- very well packed.



Nice vintage goodness, but it does need work







The old manometer fluid had leaked into the case and gummed everything up. In addition, the old rubber vacuum hoses were dry rotted and the manometer glass tube was caked with old manometer fluid and calcium deposits. In addition the stainless steel case needed a good polishing with compound.

Many of the outer shell sheet metal screws were rusted and frozen solid from the leaking manometer fluid. So I had to carefully grind them off. Since the manometer tube is not broken, the fluid probably leaked when the manometer was stored laying down; which allowed the fluid to leak out the top of the tube and into the case.
In these old tube gauges, the fluid was Mercury based, so being careful in the cleaning process pays off  at this stage. Modern fluids are not Mercury based.



The manometer head looks intact and only needs some cleaning.



The plastic scale cover looks bad, but some polishing compound will make it nice and clear again. It won't change the vintage color patina that has colored the plastic though. I like that vintage color, so I'm leaving it instead of making a new plastic cover.



Next comes the most difficult part - separating the fragile glass manometer tube from the head so the tube can be thoroughly cleaned with alcohol. Talk about nerve-racking!! one wrong move and that tube is toast.



The tube sits in some rubber packing in the head unit, and it's held in place with a packing nut.



The tube was cleaned with brake cleaner and then rinsed several times with rubbing alcohol to give it a clear look again. Then it was reinserted into the packing and the packing nut was gently pushed home again. I was sweating "bullets" because one slip of the wrench and the tube is a goner.



Here's everything cleaned, polished, and laid out for reassembly. Tomorrow I need to get some new vacuum tubing and some small stainless sheetmetal screw to be able to assemble the case again. Let's hope for the best -- LOL





This is a true find for me, so I'm going slow on this one --


Offline goodfellow

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Re: Rare Sun Manometer -- refurbish
« Reply #1 on: October 10, 2020, 11:56:13 AM »
Finished it off this afternoon and installed the manometer in the Sun MDT distributor tester
First I installed new vacuum hoses -- I heated the hoses on the end to make them pliable and then slid them on the tubes -- when they cool down, they won't come off.



The vacuum ports were cleaned and polished along with the scale







Finally the bronze cap was polished and the tube was installed in the stainless case





The cleaned plastic cover was reinstalled and it looks great -- nice and vintage





The the entire tube was installed in the distributor tester -- looks great!!! You can see why these things took a beating. They stick way out and are quite fragile.







It's pretty good looking in this condition -- time for an adult beverage!