Scott

I have had redline gauge problems and now it is getting out of hand. Or I have a major engine pressure problem!

My port oil pressure goes sky high and the red light comes on tap the gauge and it comes back to normal. This is a no brainier the gauge is junk and will be replaced! The starboard side has always been a issue with low idle pressure making the red light come on at 19 to 20lbs even though the light is set for 5 or 7lbs. (gauge and sender have both been replaced and yes they act a little different but still not consistent) Mechanical gauge confirms that there is at least 20lbs at idle.

This weekend running around 3700rpm all of a sudden the same gauge starts to fall below 20lbs pulsing around 10lbs to 0 with the red light on!! I checked the oil temp and both engines were around 180 degrees and falling (at idle) infra red sensor shot at filter and remote pad. The slower the engine ran the better the oil pressure 20+ at idle as soon as I would take off the gauge would start pulsing again. At no time did the audible system kick in these are all separate components. I checked the dipstick and had clean oil up to the full mark. I also have a new Melling's H.V. pump with a welded and braced pickup tube.

I know that I have to hook the mechanical gauge back up and confirm that it is good or bad but Wow this is nerve racking any ideas of what could be going on? We have talked about these gauges in the past but are they really that bad? Or do I have a classic oiling symptom? I can't F****g stand running with the oil gauges all over the place even if I confirm its another problem other than pressure it's too nerve racking. How are the regular non-Redline gauges? Or do I start running the tubes up to my dash for mechanical gauges?

GregP

Had two flaky redline oil gauges. First would read off the scale high with the low pressure light on. Second would read about 25 psi high (even with the engine not running) with the low pressure light on. Both were intermittent.

Gaffrig replaced the last one free, and so far the replacement has been working fine.

-Greg

Scott

Greg I knew you would reply to this thread I just can't believe it is only a couple of us having problems This weekend I will hook up the mechanical and post the results. I already know that it will be O.K. because the audible alarm never went off!
Stupid Gauges (in my best Homer voice)

candyman35

Same problem here with a red line oil pressure gauge. Mine likes to twitch.

GregP

I have mechanical gauges permenantly plumbed at the filter housings. Always check them and compare to the electrics before I go out.

I also have one fuel gauge that does the same kind of stuff, reads almost random, sometimes with the light on and sometimes not. It doesn't bother me much (the other tank always reads normal so I know how much fuel I "really" have) and havn't spent the time and $$ to replace it yet.

-Greg

THRILLSEEKER

Scott, (IF) the problem would happen to be actual pressure instead of the guage itself, one thing you may want to consider is the new pump. Did you gut the new pump before you welded the pickup tube in place? if not the heat from welding could have weakened the spring and possibly warped other pump components causing it to not function properly. I know its far fetched but something to consider.

Also what is the possibility of other electrical interference causing the guage to go nuts

THRILLSEEKER

Key your Nextel and see if it makes the guage go nuts they seem to have that effect on speakers and my plants computer system

Iggy

Funny you should mention that. I can hear my AT&T (Nokia) phone ring through the computer speakers prior to the phone actually ringing. Wierd.

Scott

Found the problem
After hooking up my mechanical gauge found that I had great oil pressure. Tried swapping just about anything I could think of behind the dash, even hooked up both gauges at the same time (They both pulsed).
Finally hooked up a wire from the sensor directly to the gauge and it worked

I ended up messing with the sensor connection and also messed with the large engine connector it ended up working again like it used to the light still comes on at 22lbs @ idle and the other one still has to be tapped when it pegs over and the red light comes on. Did I mention I have to tap on one of my voltage gauges to get the correct reading

I am not impressed with this series gauge

Raypanic

I was going to suggest running a new wire direct to the gauge. My PQ has some wiring issues too. Also on the new HP 500's I see the oil pressure wire has like a press on type connector with a boot. Maybe if your is the same it's dirty or loose.