oil pressure gauge

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RobsRR
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My Cars: 1971 Plymouth RoadRunner

oil pressure gauge

Post by RobsRR » Sun Feb 12, 2017 9:39 pm

I have noticed on my 71 RR that it takes about 5 or 6 seconds for my factory oil pressure gauge to read. It comes up slow but then seems to be fine. Checked with a mechanical gauge it shows instant pressure upon start up. I then changed the factory sender same results, slow to register when starting. I don't remember the factory gauge being so slow to register. The wiring is in good shape and I have done the Mad Electric modifications. Maybe it is fine just wondering?

rradar71
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Re: oil pressure gauge

Post by rradar71 » Sun Feb 12, 2017 10:31 pm

My oil pressure and fuel gauge both come up slow. I'm not to quick anymore either.

71bird
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Re: oil pressure gauge

Post by 71bird » Sun Feb 12, 2017 10:50 pm

What is the Mad electrical mod, please? Maybe the voltage regulator for the gauges is working slowly, I would change to one of the new digital ones from Real Time Engineering. Does your car have the resistance wire that goes between the sending unit and the wiring harness? I don't know what that wire does, but my car has one, and it is shown in the wiring schematic in the service manual.
71 Road Runner - J68

rradar71
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Re: oil pressure gauge

Post by rradar71 » Mon Feb 13, 2017 9:53 am

http://www.madelectrical.com/electrical ... uges.shtml
I used the search function to find this.

71bird
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My Cars: 69 Coronet 4 door.71 Road Runner. 71Dodge Tradesman 100 Van. 75 Dodge Dart. 95 Dodge Neon.
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Re: oil pressure gauge

Post by 71bird » Mon Feb 13, 2017 1:42 pm

Oh, ya, now I remember it. Thanks.
71 Road Runner - J68

RobsRR
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Re: oil pressure gauge

Post by RobsRR » Mon Feb 13, 2017 8:41 pm

I saw somewhere that it might be the anti drain valve on the oil filter not working properly. I will change the filter and see.

71bird
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My Cars: 69 Coronet 4 door.71 Road Runner. 71Dodge Tradesman 100 Van. 75 Dodge Dart. 95 Dodge Neon.
Location: morristown,tn.

Re: oil pressure gauge

Post by 71bird » Mon Feb 13, 2017 10:58 pm

Some filters don't have a anti drain valve, try a completely different brand, or number.
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rradar71
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Re: oil pressure gauge

Post by rradar71 » Tue Feb 21, 2017 11:10 am

71bird wrote:Some filters don't have a anti drain valve, try a completely different brand, or number.
A friend of mine, who was a mechanic (before he retired) and worked on a lot of cars back in the day, had suggested to me that instead of buying the filters that advertise the most filtering, to buy the cheaper ones instead. His thinking was, that the cheaper ones would restrict flow less and the oil was changed frequently (as per miles) anyway. Does this make sense?

71bird
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Re: oil pressure gauge

Post by 71bird » Tue Feb 21, 2017 11:37 am

Actually yes. Back in the day, I noticed a difference in oil pressure between a Fram HP1, and a regular Fram filter. I think the HP1 had less pressure, but proabaly flowed better. Now a days, most ALL filters by pass most of the oil anyway. The bypass valve opens at way to low of a pressure. Mopar has a filter that doesn't do this, but I don't know which one it is, maybe a Viper filter.
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rradar71
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Re: oil pressure gauge

Post by rradar71 » Tue Feb 21, 2017 2:01 pm

I would think you would get better flow with the HP1. Actually I was thinking the difference between the old Fram and the Extra Guard filters. I think they must all be the extra guard ones now. Apparently, the HP1 filters are available, but I don't think I could squeeze one between the headers. Correct me if I'm wrong, but doesn't the oil get to the pressure gauge after going through the filter.

71bird
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My Cars: 69 Coronet 4 door.71 Road Runner. 71Dodge Tradesman 100 Van. 75 Dodge Dart. 95 Dodge Neon.
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Re: oil pressure gauge

Post by 71bird » Tue Feb 21, 2017 7:06 pm

Small block, or big block?
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rradar71
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Re: oil pressure gauge

Post by rradar71 » Tue Feb 21, 2017 10:23 pm

Small block.

71bird
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Re: oil pressure gauge

Post by 71bird » Tue Feb 21, 2017 10:29 pm

Don't know about a small block. Look in the service manual, it should tell.
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road chicken
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Re: oil pressure gauge

Post by road chicken » Sun Mar 05, 2017 6:17 pm

Doesn't matter if its a small or big block, the sender / circuit is almost identical for the gauge. It is normal for it to take a few seconds to respond to the resistance change at the sender. The fuel gauge works in a similar way. it keep the gauges from bouncing with each little change in pressure.
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rr6pak
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Re: oil pressure gauge

Post by rr6pak » Sun Mar 05, 2017 7:47 pm

rradar71 wrote:http://www.madelectrical.com/electrical ... uges.shtml
I used the search function to find this.
When I had my cluster re-built, I had the ammeter replaced with a voltmeter. Then When the instrument wiring was installed, I bypassed the ammeter wires, cut, spliced together, shrink wrap and called it done. The cluster doesn't look altered what so ever. Wish I could figure out re-sizing pictures to show

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