Gaffrig Red-Line gauge failures
 

Is anyone else having problems with Gaffrig Red Line gauges failing? I am having recurring problems with my redline oil pressure gauges. I e-mailed Gaffrig (both of them actually since I can never remember which Gaffrig is which), but only got a reply from the one who doesn't make my redline gauges.

Last fall I had the first gauge failure. The gauge would read off the scale for high pressure and the low pressure light would illuminate at the same time. The gauge would do this as soon as electrical power was applied, with or without the engine running. I "verified" it to be the gauge as if I connected another gauge into the same circuit (even did it at the same time) the other gauge (also a redline oil) would read normally. I also have a mechanical pressure gauge on the engine which showed the pressure was normal. As a final test, I bypassed all the boat wiring and ran a jumper wire direct from the sender to the gauge with the same results.

Since I was pretty well convinced it was a bad gauge, I replaced the gauge and it worked for about 4 running hours last season. This spring, after about 2 hours of running time, the new gauge has started reading about 25 psi high (I can compare it to my engine mounted mechanical gauges, also it will read 25 psi when the engine is not running but electrical power is switched on), again with the low pressure light also illuminated. Just for grins and since I had one on the shelf I put in a new Gaffrig sender. The problem went away ... but came back on the second run out on Sunday. Since the problem appears to be intermittent I restarted the motor several times to see if it would correct itself, but kept getting the bad readings.

Knowing that the oil pressure was really ok (I checked my mechanical gauge) I went out for a short run with my daughter anyway (just can't say No to your kids, can you). Made the usual idle out and a couple of minutes after getting on plane the gauge suddenly started to read "correct" pressures and the low light went out. It worked fine the rest of the time out and during the idle in. Did a couple more re-starts during the engine flush and it kept working fine.

This gauge failure is slightly different than the first, as it does "react" with true oil pressure variations, but reads high. The prior gauge just read off the scale with no movement with actual oil pressure levels.


Is there any signal value which should cause the gauge to read both low warning and higher than true pressure at the same time? Has anyone similar problems with this gauge series?

One of my fuel gauges also has this intermittent off-scale high combined with low level warning light behavior (it will also sometimes read suddenly empty), but I have always attributed it to a bad sender. I have never tried to replace the in-tank unit to check it. I am beginning to believe that this is more likely also a problem with the gauge now that I've seen the same behavior with the oil gauges. I have run a bypass wire from the tank at the dock to see if it was a bad connection or wire, but everytime I did "anything" it would fix the problem for a while, then come back.


The first gauge had a couple of years of use before failing, the latest gauge is essentially brand new. If I can't isolate and eliminate these problems I will have to switch out the entire panel to some other more reliable gauges as I'm getting tired of never being able to know for sure if they will work or not when I want to go out for a ride.

-Greg

Did you also run jumpers for the hot and ground terminals? This would rule out a problem with one of those circuits. I know you would expect to see all of the other gauges acting up as well, but sometimes electrical problems are weird.

No, I only bypassed the signal. All the grounds and hots tested ok with my digital VOM, and all the gauges are tied together at the panel for that engine.

At one time I had the grounds for both electrical systems tied at both the motors and at the panel, but I measured a couple mili-volt difference at the panel when I removed the tie so took it off to eliminate the possibilty of a ground loop.

Since the oil gauge and fuel gauge both act up, but at different times, and the water temp, oil temp, tach and volt gauges all stay ok, I guess I find it hard to believe it is a power or ground problem.

-Greg

Assume nothing

My money is on a bad ground to the gauges.

But why only one gauge, and it checks good with the meter? I'll take another look at the pins in the engine connector but don't expect anything. Guess I can take the old gauge and hook it up to power and signal and no ground just to see if that makes it read high and low at the same time.

-Greg

Make sure that the gauge wiring on the ground side has a clean connection all the way around the ring lug. Even a small bit of shrink tubing or corrosion can make just that one gauge fluctuate.
You may also have a cooroded or partially broken wir on the ground side that is effected by the vibration.

Also make sure that there is no teflon tape or pipe dope on the threads of the sending unit.

There is no tape or dope used on the sender threads.

All the gauge grounds are daisy-chained at the panel and the oil pressure is in the middle of the chain. All the panel wiring is new from when the panels were changed about 2 years ago. I checked for a loose terminal crimp, but they all look ok. All terminals are ring bolt type, so it isn't a loose "plug" terminal.

The wires might be long enough to swap the ground from the oil gauge with another to see if it migrates ... although since I can't always reproduce it it is hard to tell what "works" or not.

-Greg

I have the same problem with one of my oil gauges. This has been an on going problem for me. I have tried most of the above and come up with nothing. I have talked to Gaffrig and they don't have an answer. What I can't figure out is why would the light come on when it is set for 10lbs or less while the needle shows presssure all over the place. I of course have run a machanical gauge to make sure that I do have normal pressure. I have switched the senders I have replaced the gauge. The only one thing I have noticed is that it seems to only act up when heated up and running. If I shut down and restart it may go away for an hour or may come back right away (very intermittent). I plan on sending one of my defective gauges back to Gaffrig. I may copy this thread and send it along with the gauge.

Scott -

Thanks for the reply. Glad I'm not the only one going crazy trying to track this down. Please let me know if you find a solution.

-Greg

Since you have checked evrything in the wiring out, it sounds like it could be a defective gauge. If it were me I would send it back to the company for repair or just buy a new onr.

I've already bought a new one, which also is "bad?". I tried contacting their customer service but havn't gotten any reply. I'll probably call Eddie Marine (who I bought the replacement through).

-Greg

I had exactly the same problem with red line series oil pressure gauge. Tried too many fixes and finally installed standard oil pressure gauge (not red line series) and have had no more trouble. I like the red line as an idea but I would never see that little light anyway. Now my gauge is trust worthy. I never felt comfortable with oil pressure fluctuating before changing the gauge. Unless your dead set on running the red line series gauge I would just install a standard gauge and I think your problem would go away. Know anyone you can borrow a standard gauge from for a day and try? One last thing I have to mention and not to state the obvious but you are running a Gaffrig sending unit correct.

I have the same problem with one of their water temperature gauges. I also have checked everything shy of replacing the gauge, but I'm not convinced it is the gauge. Here's why: Temp read OK for a while (140F, HP500 engine) and then starts to creep up to 180-200, or may just "jump" to 180-200 and stays there. If I then move the tabs (K-planes) or change the trim on the drive, the temp gauge "jumps" back to 140 and may, or may not, stay there. Grounds are all daisy chained on the gauges, and I think all of the "hots" are, too. Temp gauge is the only one that does this! Checked ground by jumpering it direct, checked sending unit with ohm meter and tested it against a brand new sender, both read the same and reacted the same to temp changes. What bothers me, is that by applying a "load" on the electrical system (moving the drive or tabs), the temp gauge reacts (goes back to 140F). That indicates electrical noise getting into the signal wire, floating ground, or floating "hot" voltage. But why is the temp gauge the only one affected??? :confused: :confused:

paradigm shift - Yep, running the second (now) Gaffrig sending unit. Never thought it was the real problem, but changed it to another new one "just in case". It's beginning to sound like Gaffrig has a real problem with this series gauge.

-Greg

I sent the Gauge and a letter out today I will post the results.

Ed at Gaffrig sent me a new gauge at no charge. He also (after I asked) talked me into changing my stock senders over to the units they sell. Not a big deal except that they are VERY difficult to get to, it took me almost one hour per motor with cut up hands and bruised ribs (man did that job suck).
I am not convinced this will be the solution since I have already changed the gauge and I have swapped the sending units. I did a lot of wire tracing to make sure all connections are good. Just can't imagine how the gauge can read pressure (erratic) but never below the set 10lbs and still have the light blink on and off. I will also add that they checked my old gauge and found no problems and were still willing to comp me a new gauge out of warranty.
I will post again after I get out on the water and let you know if the problem has been solved.

Scott

Hi Scott,

I have run the gauge with and without the Gaffrig senders, and have replaced the sender with no long-lasting effect (it did make it work correctly for a couple of hours, but I think it was a fluke).

Since I have two flaky gauges and one is on the shelf I played a few games with it. Running no ground just sender it will read off the scale high, but no "red light". Running no sender but ground it reads zero with the red light (no great surprise there). By connecting and disconnecting the ground I can get the red light to blink briefly, but not to stay on. I have never been able to duplicate the high with red light that it had before.

The "new" gauge and sender in the boat continues to be intermittent. It usually goes to "bad" mode (red light one and reads 25 psi with the engine off, and not surprisingly 25 psi higher than true when the motor is running) as soon as I turn the switch, but returns to reading "correctly" after running for a while. It will do this while the boat is setting still on the lift, so it's VERY unlikely it is a loose connection somewhere. So far it has never gone from "correct" to "bad" mode once reading correctly without turning the engine (power) off and starting a new cycle.

I took the boat down this morning to be pulled for painting. The gauge powered up as "bad", went to "good" about 1/4 mile after coming up on plane, and stayed "good" for the 45 min run to the ramp.

I'm just going to dump the red-line gauges when it gets back from the shop,. I need to find out whose white face gauges look similar so I can swap them out a few at a time instead of doing the whole panel again (since so far only one oil pressure and oil fuel level have been acting up).

-Greg

Only failure that I've had so far is moisture in the gauge. The culpirts have been replaced by Livorsi.

I HATE RED LINE GAGES
 

no joke all of the one's I have had failed in one year ,,no b/s,really ,thats after hours setting their electronic fuel gague

I have moisture in 5 of my guages. 4 of them Redline.

I thought they were supposed to be moisture proof???