low oil pressure after general inspection. KJ 2006 3.7

[KJlibertyBR]

Sou brasileiro e tenho um Kj 2006 3.7, aqui no Brasil esse veículo é raro, então não tem muito conteúdo sobre ele.

Acontece que a luz de pressão do óleo está acendendo em marcha lenta, isso ocorreu após a manutenção do motor. O cabeçote foi retrabalhado, os pistões e anéis foram substituídos, todas as juntas e mancais da biela (como não removi o virabrequim porque não estava riscado, mantive os mancais fixos e também não vi como estavam), todas as peças foram trocadas sem manutenção STD.

Motor a princípio tudo ok, o mecânico não quis trocar a bomba de óleo porque disse que como tem engrenagens não perde pressão. Porém, agora que o motor está montado, a luz do óleo começa a acender quando o motor está quente e em marcha lenta (80°)
Eu pergunto a vocês, que estão acostumados, esses motores costumam ter bomba de óleo com defeito? O motor tem válvula de alívio de pressão que pode estar com defeito?

Eu uso óleo 10w40 (na minha cidade a temperatura fica sempre em torno de 15 a 30°), fiz manutenção no motor porque ele começou a soltar muita fumaça na primeira partida, então aproveitei e fiz uma revisão geral.

 

[LibertyTC]

Translated:
I'm Brazilian and I have a 2006 Kj 3.7. This vehicle is rare here in Brazil, so there isn't much information about it.The thing is that the oil pressure light is coming on at idle. This happened after engine maintenance. The cylinder head was reworked, the pistons and rings were replaced, all the gaskets and connecting rod bearings (since I didn't remove the crankshaft because it wasn't scratched, I kept the bearings fixed and also didn't see how they were), all the parts were replaced without STD maintenance.The engine was ok at first, the mechanic didn't want to change the oil pump because he said that since it has gears it doesn't lose pressure. However, now that the engine is assembled, the oil light starts coming on when the engine is hot and at idle (80°).I ask you, who are used to it, do these engines usually have a faulty oil pump? Does the engine have a pressure relief valve that could be faulty?I use 10w40 oil (in my city the temperature is always around 15 to 30°), I did maintenance on the engine because it started to smoke a lot when it was first started, so I took the opportunity to do a general overhaul.

 

[DadOSix]

The only way to tell for sure is to attach a mechanical gauge to the engine and see the actual pressure. That oil sender is just a ‘switch’ and they can send a low pressure signal at times. Perhaps the port (orifice) on the switch is plugged up or partially obstructed by oil sludge.

Also, the mechanic needs to re-think the pump logic. Those gears can and do wear - due to , say, low oil level or extended maintenance intervals ( waiting too long between changes)

 

[KJlibertyBR]

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[KJlibertyBR]

The only way to tell for sure is to attach a mechanical gauge to the engine and see the actual pressure. That oil sender is just a ‘switch’ and they can send a low pressure signal at times. Perhaps the port (orifice) on the switch is plugged up or partially obstructed by oil sludge.

Also, the mechanic needs to re-think the pump logic. Those gears can and do wear - due to , say, low oil level or extended maintenance intervals ( waiting too long between changes)

just letting you know that all the temperature measurements I provided in the first question were in Celsius.

 

[KJlibertyBR]

The only way to tell for sure is to attach a mechanical gauge to the engine and see the actual pressure. That oil sender is just a ‘switch’ and they can send a low pressure signal at times. Perhaps the port (orifice) on the switch is plugged up or partially obstructed by oil sludge.

Also, the mechanic needs to re-think the pump logic. Those gears can and do wear - due to , say, low oil level or extended maintenance intervals ( waiting too long between changes)

Today I put the oil pressure gauge on, with the vehicle warm, idling, water temperature at 90°C or 194°F, the pressure gauge is showing between 6 and 7psi.

When accelerating at 4000 rpm it showed around 45/50 psi.

I noticed that the oil switch is leaking oil through the sensor and coming out at the electrical connector itself.

I ask you, what is the correct oil pressure for this engine?