Broken gauge or other problems?

[airhead04]

Ok, I have a fresh new rebuilt motor in my car. Ive put maybe 300 miles on it. My oil pressure when cold start is 40+ psi. On a warm start it hits about 10 psi then slowly drops to 0, according to the gauge.

Other things I ve noticed is that 1st thru 4th gear for every 1k rpm the meter reads 10 to 11 psi of oil. But in 5th at around 1500 rpms the gauge reads 10. Once I get to 2k rpms then it slowly creeps up to about 20psi of oil sometimes only making it to 18psi of oil.

Oil pump wasnt shimmed. And I had to use the stock crush bent oil line for in the pan.

Im running vavoline 10w40 conventional oil.

So I need to know if I have a bigger problem then the gauge. I went to auto zone to get a mechanical oil gauge to see the pressure but they didnt have one available at the time.

 

[airhead04]

anyone?

 

[airhead04]

No helpy? =[

 

[BigKO]

I would recommend getting a oil pressure tester, and threading it into the block where the stock oil pressure sending unit is, so that you can get a more accurate reading. This will let you know what is going on, This page in the TSRM tells you exactly what specs should be for s stock system: http://cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=LU&P=4.
this should give you a lot of help.

 

[mkiiichip]

So have you done the TSRM checks?
Stock idle gauge readings (not reliable) will read 0 at hot idle.

Post your readings, (with an actual pressure gauge) at idle and 3000 RPM?

Why are you running valvoline? let alone 10w40?

 

[BigKO]

Hmm Idk about the stock gauge reading zero at hot idle, both before and after rebuild mine never did that. But idk for sure so yeah... lol just my experience

 

[jdub]

I would recommend getting a oil pressure tester, and threading it into the block where the stock oil pressure sending unit is, so that you can get a more accurate reading. This will let you know what is going on, This page in the TSRM tells you exactly what specs should be for s stock system: http://cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=LU&P=4.
this should give you a lot of help.

This is exactly what you should do. Airhead - The reason you did not get a response from me is you already knew that - until you do, any response is pure speculation.

So have you done the TSRM checks?
Stock idle gauge readings (not reliable) will read 0 at hot idle.

Post your readings, (with an actual pressure gauge) at idle and 3000 RPM?

Why are you running valvoline? let alone 10w40?

While the stock gauge is slow, it is fairly accurate - unless there is a problem with the gauge or the sender. The stock gauge should NEVER read zero at idle if it is working correctly and that includes with the engine hot. I do agree with you about his choice of oil - not exactly the best of choices

 

[airhead04]

Ill be getting one tomorrow.

With the current electronic gauge my readings are idle 50+psi (start up/cold) with a warm engine idle is at 4psi at 3k it slowly climbs to 30psi....but i mean slow.

 

[jdub]

So, this is not a stock gauge? It would have been nice to know that...care to share who made the gauge/sending unit and where the sending unit is located?

 

[airhead04]

Sorry jdub. Its a prosport gauge/sender, and its located in the stock position.

I went to Advanced Auto today to get the Oil pressure tester and they do not offer one. At least not the ones here in Kissimmee fl. So I will try NAPA tomorrow.

The reason Im running 10w40 conventional is because this is a rebuilt motor. I ran 30w Castrol for the first 50 miles then changed to the 10w40.

 

[jdub]

It could very easily be the gauge.

Because it's rebuilt is not a good reason to use a 10W-40...I've been running 0W-30 Castrol European Formula (aka German Castrol) since break-in on my motor. A PAO or ester based synthetic is far superior to any conventional oil out there, especially in a rebuilt motor. Might want to read the Motor Oil 101 link in my sig

 

[airhead04]

The reason I grabbed 10w40 is because I went off what you mentioned in the Proper break in procedures. In post number 3 you said 100 to 200 miles use a 10w30 dino oil. I couldnt find 30 so I grabbed 40 (Not a good excuse, but Im not trying to make one). Im due for my oil change this week. So Ill grab a better oil.

Which aftermarket gauge would you recommend sir?

 

[RockPaperSwoRD]

summitracing, buy the cheapest one you can find+a sending unit. it shouldnt be more than like 40 bucks total. plant it in your gauge pod

 

[airhead04]

I think Im going to grab an Auto meter. They seem to be one of the best on the market.