Ok d40 yd25 powered, drive around town for 2000kms not a prob. Hit the open road over the weekend approached some long stretch hills at around 110kmph temp gauge starts to rise, once the hill plateaus out temp gauge settles back to normal. Car has had a new Tstat and water pump. My next thoughts are a blocked rad? Cores corroding braking down And restricting flow? I don't know,, could it be a fan clutch??? If you start the car cold the fan only revs up for around 5seconds then cuts out?? If you shut the engine down it continues to spin on, should it just stop??!?? I haven't ruled out a cracked head but I'm not convinced, it's not using water, no signs of water in oil or oil in water, no sweet smell from exhaust, plenty of power, no leaks etc does that rule the head out?? Please throw some options at me guys. Thanks heaps oh ps it's an 07 with 185,000kms
D40 strange overheating
- Thread starter vool104
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Sounds to me like something inhibiting flow in the radiator cores. Mine is going to be checked on Friday for a similar issue, I suspect blocked cores in mine as everything else is working perfectly.
The fan sounds like it's doing what it's supposed to. Until the engine is hot, the fan won't spin hard. The fluid coupling behind it won't engage until the engine is hot enough, so the fan will both seem to spin poorly while the engine is running, and it will continue spinning after the engine has shut off - because the fluid coupling hasn't engaged.
Thankfully there's an easy (and cheap) way to test the fluid couple. Go drive the car until the engine has warmed up to normal operating temperature. Pull over somewhere safe, turn off the engine, pop the bonnet and give the fan a spin. It should be hard to turn over - if so, it's working normally.
The fan sounds like it's doing what it's supposed to. Until the engine is hot, the fan won't spin hard. The fluid coupling behind it won't engage until the engine is hot enough, so the fan will both seem to spin poorly while the engine is running, and it will continue spinning after the engine has shut off - because the fluid coupling hasn't engaged.
Thankfully there's an easy (and cheap) way to test the fluid couple. Go drive the car until the engine has warmed up to normal operating temperature. Pull over somewhere safe, turn off the engine, pop the bonnet and give the fan a spin. It should be hard to turn over - if so, it's working normally.
I did that today mate, after reading one of you posts before, and there is no resistance at all. My thoughts were is if the engine begins to work hard under load shouldn't it kick in? As temp rises? If it was faulty it way not kick in
I'd rule out the head gasket if you did a compression test, but sounds like it is the fluid couple that's at fault.
When the engine is hot, that fan should stick to its shaft nearly like it's been glued on. If it's not, it won't draw the air = the radiator isn't as effective.
Not the first time the fluid couple has failed.
Nizzbits.com.au would be my choice for a genuine part if I didn't want to pay Nissan dealer prices for it.
When the engine is hot, that fan should stick to its shaft nearly like it's been glued on. If it's not, it won't draw the air = the radiator isn't as effective.
Not the first time the fluid couple has failed.
Nizzbits.com.au would be my choice for a genuine part if I didn't want to pay Nissan dealer prices for it.
Depends on the speed, temperature of the coolant and the state of the air conditioning system. Even if the engine is under the minimum temperature that it would use the fan, if you turn on the A/C the fan will come on. That's normal operation.
There's a chart on page 351 of EC.pdf in the electronic manual (discusses overheating) and it probably explains things better than I do!
There's a chart on page 351 of EC.pdf in the electronic manual (discusses overheating) and it probably explains things better than I do!
kevvyp
Member
My 07 D40 has the same symptoms, long hills = temp increase, I have recently purchased a Bluetooth OBD reader and I use Torque with my phone, the temp goes from 87 at idle to 93 at speed and back to 87 at rest
(around town), I was thinking of checking the radiator as it seems like a flow problem to me, it will be interesting to see how yours shapes up tony.
Question in regards to A/C fan, should the fan come on when the A/C is turned on? or is it a specified temp? my fan does not come on when the ac is first turned on and I am yet to hear it running.(only used the ac once since owning the truck)
kevvyp
Member
I think the plan will be a new radiator, probably in the next week or so, i will post up the results when it's done.
According to the manual, the fan on the D40 should start when the A/C is turned on - if you have someone in the cabin with a cold engine, you should get them to turn off the A/C then start the engine - you should notice the fan "not as strong as it ought to be" and when they turn on the A/C it should pick up the pace - that's how it's supposed to work.
If it's not working as expected, do the hot engine fan test as described in the second post on this thread.
If it's not working as expected, do the hot engine fan test as described in the second post on this thread.
kevvyp
Member
Thanks for that Tony, i will check it out, the viscous fan does grab more once the engine warms up, its more the electric fan i'm concerned with, how did you go with your radiator check?
Sorry to hijack your thread VOOL104 but some of this info is relevant to your problem.
Sorry to hijack your thread VOOL104 but some of this info is relevant to your problem.
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No electric fan in mine. I wonder if it was missing, lost, stolen or maybe it was playing with sharp implements when it was younger?
kevvyp
Member
kevinm1962
Member
after changing the water pump its obvious you put new coolant in did you flush the engine properly as mixing coolants can cause them to turn to jelly in motor so if you have done this you will need a proper flush. kev
