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Engine Fan running
Posted: Sun Jun 26, 2022 1:28 pm
by 00pathySE
Hey all, my 06 engine fan seems to be running all the time. On starting it roars for a few seconds than goes away as it should. But after getting hot it seems to stay on. Scan tool shows a reading around 200f. Is that too hot? Wondering if the fan clutch is bad or if the engine is running hot. On a hot engine I can spin the fan by hand about one revolution. Coolant guage shows near the middle and doesn't move once it gets there. Any ideas? Thank you.
Re: Engine Fan running
Posted: Tue Jun 28, 2022 8:09 am
by 00pathySE
Can someone tell me how many turns you can spin a good fan clutch by hand on a cold engine on your r51 Pathfinder? Or how loose the fan feels when cold when grabbing the fan near the airbox? Thanks.
Re: Engine Fan running
Posted: Tue Jun 28, 2022 4:23 pm
by palmerwmd
I'm sorry you havent had a reply yet.
I am sure there will be one soon
Re: Engine Fan running
Posted: Tue Jun 28, 2022 4:59 pm
by VStar650CL
Palmer, go give your Xterra fan clutch a spin for him. His clutch also fits '05~'15 Xterra and '05~'19 Frontier.
Re: Engine Fan running
Posted: Tue Jun 28, 2022 5:19 pm
by 00pathySE
Lol
Re: Engine Fan running
Posted: Tue Jun 28, 2022 8:06 pm
by VStar650CL
Wasn't trying to be funny. If I had a healthy X or Frontier handy, I'd spin it for you. Might see one tomorrow at the shop.
Re: Engine Fan running
Posted: Wed Jun 29, 2022 6:04 am
by palmerwmd
I'll do it today
PS to 00pathySE, my R51 is a V8 so thats why I did not do it when i saw you question first.
Re: Engine Fan running
Posted: Wed Jun 29, 2022 5:05 pm
by 00pathySE
Thank you to both of you!
Re: Engine Fan running
Posted: Wed Jun 29, 2022 8:34 pm
by palmerwmd
00pathySE wrote: ↑Wed Jun 29, 2022 5:05 pm
Thank you to both of you!
Sorry I didnt get to it today after i came backk from work the engine was real hot and did not cool down for a while ( florida)
I'll give it another shot in the morning
Re: Engine Fan running
Posted: Thu Jun 30, 2022 2:42 pm
by TooMuchControl
I had my cooling fan running even after getting off the road on non-aggressive driving.
I'm wondering if you notice that your temperature might peak for a few seconds - and then go back to normal?
This happened to me, and I only saw it when stopped a drive-thru for coffee. It spikes for a couple of seconds, but the fan kicks on and runs for what seems a minimum amount of time.
I think something might be boosting the keep the transmission cool, not just the engine.
check your transmission oil, if this is an automatic. Makes sure it's in good shape at a good level.
check your coolant tank for anything that doesn't look normal.
After I changed the tx oil, never happened again.
I think the Tx oil temperature sensor will trigger the fan to come on, even when engine coolant temperature is normal or within range.
Re: Engine Fan running
Posted: Thu Jun 30, 2022 4:04 pm
by VStar650CL
TooMuchControl wrote: ↑Thu Jun 30, 2022 2:42 pm
I had my cooling fan running even after getting off the road on non-aggressive driving.
I'm wondering if you notice that your temperature might peak for a few seconds - and then go back to normal?
This happened to me, and I only saw it when stopped a drive-thru for coffee. It spikes for a couple of seconds, but the fan kicks on and runs for what seems a minimum amount of time.
I think something might be boosting the keep the transmission cool, not just the engine.
check your transmission oil, if this is an automatic. Makes sure it's in good shape at a good level.
check your coolant tank for anything that doesn't look normal.
After I changed the tx oil, never happened again.
I think the Tx oil temperature sensor will trigger the fan to come on, even when engine coolant temperature is normal or within range.
The FSM says the ECM is only looking at engine temp and refrigerant pressure, but a hot tranny will indirectly drive up the engine temp by way of the heat exchanger, which is in the outlet tank of the radiator just before the coolant reenters the block. Keep in mind that going from driving to stopped will always cause the coolant to "cook" for a few moments because the water pump is running slower and airflow is reduced, but the coolant in the block still has a large thermal load from producing power. Until all of it circulates through the radiator, the temp in the block will momentarily spike. That's all perfectly normal, but it will often cause the ECM to ramp up the fan(s).
Re: Engine Fan running
Posted: Fri Jul 01, 2022 10:09 am
by 00pathySE
TooMuchControl wrote: ↑Thu Jun 30, 2022 2:42 pm
I had my cooling fan running even after getting off the road on non-aggressive driving.
I'm wondering if you notice that your temperature might peak for a few seconds - and then go back to normal?
This happened to me, and I only saw it when stopped a drive-thru for coffee. It spikes for a couple of seconds, but the fan kicks on and runs for what seems a minimum amount of time.
I think something might be boosting the keep the transmission cool, not just the engine.
check your transmission oil, if this is an automatic. Makes sure it's in good shape at a good level.
check your coolant tank for anything that doesn't look normal.
After I changed the tx oil, never happened again.
I think the Tx oil temperature sensor will trigger the fan to come on, even when engine coolant temperature is normal or within range.
Coolant and tx oil are really good. I notice it comes on as soon as there is stop and go traffic. Highway is fine for the most part (I think). Not sure what the tx temp is, but I haven't seen coolant temp go over 206, so it's not overheating. Runs great.
Re: Engine Fan running
Posted: Fri Jul 01, 2022 10:45 am
by VStar650CL
00pathySE wrote: ↑Fri Jul 01, 2022 10:09 am
Coolant and tx oil are really good. I notice it comes on as soon as there is stop and go traffic. Highway is fine for the most part (I think). Not sure what the tx temp is, but I haven't seen coolant temp go over 206, so it's not overheating. Runs great.
205F is right where the ECM kicks the electric fan to high speed, so it sounds like you're running borderline hot in traffic. That might very well mean a weak clutch on the belt-driven fan. We didn't get any applicable vehicles through the shop the last two days, so I wasn't able to check one for you.
Re: Engine Fan running
Posted: Fri Jul 01, 2022 10:56 am
by 00pathySE
Hmm...that's interesting, thanks! When I spin the fan cold or after its been driven it feels like it has the exact same tension. So maybe it is shot. I'd be really curious to know what a good one feels like.
Re: Engine Fan running
Posted: Fri Jul 01, 2022 11:29 am
by VStar650CL
00pathySE wrote: ↑Fri Jul 01, 2022 10:56 am
Hmm...that's interesting, thanks! When I spin the fan cold or after its been driven it feels like it has the exact same tension. So maybe it is shot. I'd be really curious to know what a good one feels like.
That's a stuck valve in the clutch or all fluid has leaked out. Any viscous fan clutch should give you more resistance hot than cold. The way they work is with a bimetal element (yes, just like an old choke spring) that gradually opens a valve as it heats up, allowing flow through a viscous coupling that creates shear between a pair of plates and results in more resistance. This is a great vid explaining how they work:
https://www.youtube.com/watch?v=UwM4OqsLek4
You can't create a lot of centrifugal action with a hand, but the clutch should still have noticeably more resistance hot than cold. If it's spinning about the same hot or cold, it's definitely shot.