what is this thing? Robinsons Automotive Service Gauge

Are you sure it is a pressure gage and not a vacuum gage?

Wes

OK, one point for Wes - it is a vacuum gauge.

Now, what is this thing? Fuel ???

Manifold Pressure in inches of mercury.

JC

Manifold vacuum used to estimate MPG?

--Winston

My guess is that is a carb balancing guage for twin carb arrangements.The needle valves are used to center the gauge range prior to carb airflow adjustment. Steve

I don't think so, nor do I think it's a balancing device - first, it is way too old for engines with dual carbs, secondly the sight glasses are small, not tapered and have no ball, so you could see bubbles but not air flow in the way a unisyn shows it. And, none of the explanatoins to date would suggest the curved part at the bottom (by the way, there are two threaded holes, one from each side, going into that curved part at the bottom - another part clamps onto this ssembly where the cutouts are near the fittings.

I imagine that the upper needle valve is used to let bubbles into some kind of flowing fluid (fuel maybe?)

What is bugging me, is that I've seen this arrangement before somewhere, but I just can't remember where or when (does that sound like a song from about

I am pretty sure this dates from the pre WWII era - possibly early 30s to

I don't think so, I have a unisyn - these things don't look anything like this setup - but there has got to be an answer, someone must know what this is.....

if you have a hint, I can do some research, but it's pretty hard to find somethign from a picture (there is the next Google - search by picture

The curved part at the bottom looks like it would fit the steering column so a driver could watch it as he/she drove the vehicle.

The vacuum gauges I remember only had a single tube that connected to the intake manifold and warned the driver when the vacuum dropped, so did the mileage. Don't see how your unit would accomplish that.

Paul

The curved part at the bottom looks like it would fit the steering column so a driver could watch it as he/she drove the vehicle.

The vacuum gauges I remember only had a single tube that connected to the intake manifold and warned the driver when the vacuum dropped, so did the mileage. Don't see how your unit would accomplish that.

Paul

well, that's a good thought, maybe it attaches to the steering column - some early cars used a vacuum oiler, so I suppose this could monitor the vacuum and inject some bubbles so you could see that oil was being sucked into the crank case

What is it? If you have A patent # you can check it out at the U.S patent office site.

Good Luck. H.R.

Could this be part of a water injection system? They were rather popular in the 40's and 50's.

Paul

Could this be part of a water injection system? They were rather popular in the 40's and 50's.

Paul

well, that's not impossible, I guess - but some how if it ws water injection, I would think I'd see some residue, which I don't. One more hint, if anyone knows how to decode the number - the vacuum gauge is US GAUGE CO NY, and it has the number AD-2215 in tiny letters - that could be a clue as to age.

If it were water injection, I don't understand the two sight glass tubes - The device is mixing fluid from the left side (where the glass tube is missing) with air let in through the top needle valve, with the flow rate controlled by the other needle valve and letting the mixture out the right side with the glass tube. The inside of the glass is a bit discolored - kind of an oil color, but I don't smell anything other than old metal, I looked at the point of the needle valves, no hints there either.

Oh, and there is no patent number, just what may be a serial nuber (152) hand stamped into the curved part

It could be an early top end oiler.

One of the first car test instruments I bought when I first started messing with car engines was a vacuum gauge. If you know what you're doing, it can diagnose a wide variety of ills. If it fits an old timey steering column, that would be a plus, you could actually run some tests with the engine under load. Being able to bleed air in would let you see if the carb is set rich or lean, a tach would be a handy adjunct, but a tuned ear could tell whether the engine sped up or slowed down. If semi-permanently installed, you could discover what load settings would give the best performance and/or fuel economy. Probably there was a whole manual telling what it could do and how to do it. Good luck finding one...

With today's computerized sensors and closed loop engine management, practical value is probably nil.

Stan

figure 121 on your second link also seems on target - but there must be a photo of it somewhere - I'm astounded that given the wealth of knowlege here that someone hasn't said "oh, it's a XXXX"

I suspect we are gaining on it - I posted the inquiry on the AACA forum (antique auto) - maybe someone will recognize it there - it's an interesting mystery

Is it possibly from New Zealand? A Robinsons Co down there distributes a lot of gauges and test equipment hand has made many under their own name over the decades.

well, the lettering on the face says "robinson's automotive service Los Angeles", which sort of steers me away from new zealand. And a web search for the los angeles area is so far futile - (too many, nothing seems relevant).

I'm not convinced this is test equipment - it may be something that is permanently attached to the vehicle and the lettering on the face is to remind you where to take your car for service. But I still don't know for sure what it is.