Hobbs woes!

[F10]

Yeah, who ever heard of a Hobbs meter failing? Well, mine has🤦🏻‍♂️🙅🏻‍♂️😡 Can anyone give me a bit of info on how it’s wired up? I checked the spade connectors at the back of the unit. One was a bit loose, so crimped it slightly to tighten it up. Sadly, to no avail, numbers remain frozen from last flight. Next step will be to remove it and connect power to it. If it works, guess we have a power supply problem. Fortunately, they don’t seem to be too expensive, if it comes to replacing it. Any advice welcome!

[pluessy]

Engine? Hobbs brand/model?

[F10]

Gazelle, so a Rotax 912 80Hp. Not sure of Hobbs brand. Round gauge with numbers and hourglass symbol. Maint manual I have doesn’t have much info.

[onetrack]

F10 - There's nothing in the Hobbs meters that is repairable, simply buy a new one.  When you pull it out, it will have a decal with all the relevant information on it, model number, part number, voltage, polarity etc.

I have several new units of the rectangular variety, but I can't help you with a round one. Try eBay, there's usually plenty available there.

[Bernie]

Mine also had another under the panel for air frame hours from memory only activated once 40 knots was reached.

Bernie.

[F10]

12 hours ago, onetrack said:

F10 - There's nothing in the Hobbs meters that is repairable, simply buy a new one.  When you pull it out, it will have a decal with all the relevant information on it, model number, part number, voltage, polarity etc.

I have several new units of the rectangular variety, but I can't help you with a round one. Try eBay, there's usually plenty available there.

Yes, pretty much made peace with the fact a new one is on the cards. Not he’ll bent on a round one, will be happy to put in a blanking plate on the panel, or fit it in the round hole with a plate. I will PM you about yours if you may be open to selling? Cheers!

[F10]

8 hours ago, Bernie said:

Mine also had another under the panel for air frame hours from memory only activated once 40 knots was reached.

Bernie.

Yes, so does my Gazelle, hidden under the panel. Used for airframe hours indication, activated by airspeed.

[onetrack]

F10 - Yes, all the ones I have are for sale, I was in the process of putting them on eBay. The ones I have are Honeywell Hobbs (Honeywell International purchased Hobbs Corp in 2002), and they're the same as the ones the U.S. seller below, is selling.

 

https://www.ebay.com/itm/175132661015

 

They're 12-60V, bayonet-style connectors, with a sliding plastic clip held by serrations to secure the meter in the panel. I'm asking $40 for them, post included. PM me when you're ready.

[F10]

Update on my hobbs. I removed the gauge and connected it to my motorcycle 12V battery. Lo and behold, a happy ticking sound was heard, with moving number barrels! So, I had a wiring power problem. A good mate came around last Saturday, who knows his way around Rotax engines and who has built two beautiful Rans S12's. He quickly homed in on the oil pressure transmitter on the front of the engine, screwed into the oil pump housing. Turns out the hobbs meter is wired into this. Had two earth wires, one it seems for oil pressure gauge one earth wire for the hobbs. An earth wire was broken and the positive connector needed a bit of tightening. Glad the oil pressure gauge didn't pack up. An oil pressure gauge reading zero would be pretty distracting! Stable temp and a happy sounding motor would suggest a gauge failure, but still...distracting! So after sorting the wiring, all is good with the world again!