Operating temp of cooling system

Discuss topics related to the VH41DE, VH45DE, VK45DE, and VK56DE engines.
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RichZilla
Posts: 121
Joined: Mon Jul 16, 2007 11:03 pm
Car: Y34 Nissan Gloria VQ30DET 12PSi & 20" rims

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Can anyone tell me the normal operating temp of the VH45DE? Or what the Q45's radiator cap is rated to in PSi. I've got two fans on the merc and I'm still seeing apparent coolant temps of about 100 degrees celcius after driving for an hour in the hot sun and traffic.


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elwesso
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Car: 94 Infiniti Q45t 5 spd
2007 BMW M Coupe
2007 Infiniti G35 S 6MT
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Yeah you're running way too hot... The max you shoudl see is around 90C or so... Operating temp is about 80C... Once you hit 90C you start backing the timing off because the ECU thinks its overheating...

The cap spec is 11-14psi...

Q45tech
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Joined: Tue Apr 30, 2002 3:19 am
Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl

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Ecu timing retards begins at 91C [195F] and increments 1 degree advance reduction per 5F to a max of 5 degrees at 220F

A proper brand new radiater with correct functioning rubber shroud seals and viscous fan will hold 174-196F. Ideal per FSM is 176F.

Oem rad is designed for a 0.9 bar or 13.2 psi cap


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