Oil pressure gauge

[MRARTA]

hi, I have almost completed restoration of my w136 cabriolet A 1937. I have totally rebuilt the engine. When I start the engine, the oil pressure indicator goes up to 3. Is this normal? What should indicate when the engine is running and what is the normal oil pressure gauge should indicate. Can any one help me.
Regards
Arta

[BENZNARD]

Hello Mrata
Yes! When the oil is cold; a pressure of 3bars is normal and very good .When the oil is very hot ; an oil pressure of 0;5bar is admitted on these engines M136
Regards
BERNARD

[MRARTA]

Hi thanks for quick reply. The gauge only goes to 3 bar. I do not understand 0:5 bar. Can you please explain to me. Many thanks
Arta

[BENZNARD]

Hello Mrarta
What I want to say:
When the engine is hot (80°c or above) the oil is also hot ;so very fluid
If the engine is in low RPM (idle) the oil pressure pump rotates also more slowly
Consequently: oil very fluid+ slow rotation of the oil pump = low oil pressure
When the HOT engine is in idle position an oil pressure under 1bar (down to 0.5 bars )is acceptable
I hope my explanation are clear
Regards
BERNARD

[MRARTA]

Good morning
Thank you for your explanation. I fully understand now.
I have one more question when I check the battery the regulator is charging the battery a bit low. Could you please let me know where I purchase a 6 volt Bosch regulator.
Thanks again for your help.
Regards
Arta