A problem with Faria instruments

[cranetruck]

There are numerous articles in the PS magazines over the years about the grounding of the oil pressure gauge, in particular (example shown in image #1).

The Faria instruments were designed to simplify production, one coil vs two and a plastic body, molded for the components. However, there is one little detail about how the connections are made from outside to inside that reduces reliability and that is a non-gas tight connection that was gas tight on earlier instruments. The contact interface on the Faria is smooth as compared to the fluted finish on the AC, for example. The fluted pin cuts into the contact and provides a "gas tight" connection, like a crimp connection. The Faria connection will corrode over time.

As shown in image #3 Faria attempted to solve the problem by adding a "bridge" between the external connections, which helps the odds, but doesn't solve the problem.

I just replaced a Faria oil pressure gauge, which was erratic with an older AC model, which now works perfectly.

Just a heads up, friends.

 

[Recovry4x4]

Interesting. My M108 has developedvan oil pressure gauge issue. Installed a temp mechanical gauge until I can troubleshoot. Along tge way Glen from KS offered up some mechanical gauges out of the M809 series. I ordered several for my junk.

 

[cornrichard]

But the Faria gauge is new and improved. How can it be of lesser quality? Just kidding I am also less than impressed with the Faria gauges in my 915a1.

 

[Beerslayer]

I received some Faria gauges that were NOS. They looked to me to be of lesser quality than the Stewart Warner gauges that were original. Am thinking to not use them and find some good ones.

Thanks for the great technical detail. I might have missed that.

 

[papakb]

Faria has been buiding crap for the government since the days of the 151A2s. Lowest bidder, lowest quality. A good portion of them don't work right out of the box.

Something else to keep in mind is that the instrument clusters in most M series trucks are held in with fasteners that don't always guarantee good electrical contact, especially if there's too much paint or corrosion present. In the later M151s they added a ground (bonding) strap to the panel to make sure it had good electrical contact with the rest of the vehicle. In the HMMWV the problem is even worse because of it's glued construction. They had to add ground wires to the harnesses for proper operation of lights and instruments.

Same thing holds true for the composite taillights used on the later M series trucks. For whatever reason they bring the lamp grounds out seperately through the 2 mounting bolts. If you only have 1 bolt in place, half of your lights won't work.


Kurt