External oil cooler question MY 90 and newer
#1
External oil cooler question MY 90 and newer
On the MY 90 and newer, there is an external oil cooler. I noticed that the cooler is not located in the path of the cooling fan airflow. Is is located below the radiator/cooling fan assembly. Oil cooling while at speed would seem fine, but how does the oil cool when you are standing still (stoplight, rush hour traffic)?
#3
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Your 1990+ front spoiler has these cutouts:
Which feed this ductwork:
Rear face of the ductwork:
Which mounts here on the two exposed studs:
Which feed this ductwork:
Rear face of the ductwork:
Which mounts here on the two exposed studs:
#4
I agree and my car has all these parts, but since the cooler is mounted right below the radiator, and the fan is mounted right behind the radiator (and pulls air in thru the radiator, how can the fan pull in air thru the oil cooler. The geometry doesn't seem to work.
The ducting looks like it's there for directing air when the car is moving.
I need to take a better look. Thanks for the responses.
The ducting looks like it's there for directing air when the car is moving.
I need to take a better look. Thanks for the responses.
#5
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Perhaps the assumption was that if you're not moving, your car is idling along at less than 1K rpm and not generating enough heat that you'd need to circulate the oil in addition to the coolant. IOW, circulating coolant is enough to remove the heat load at idle/slow speeds.
This is just a guess, I confess that I have never managed to understand the circulation of oil in these engines through the filter, oil pressure regulator pistons and oil cooler lines.
This is just a guess, I confess that I have never managed to understand the circulation of oil in these engines through the filter, oil pressure regulator pistons and oil cooler lines.
#6
I was thinking along the same lines. Small load at idle, block cooling might be adequate.
The reason that I wondered is that I have read a fair number of 'low oil pressure at idle' stories lately (summer driving). A fair number of these stories were for cars MY 90 and newer.
It's nice to have others to bounce questions off.
The reason that I wondered is that I have read a fair number of 'low oil pressure at idle' stories lately (summer driving). A fair number of these stories were for cars MY 90 and newer.
It's nice to have others to bounce questions off.
#7
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While it is true the external oil cooler has no forced airflow, it offers the advantage of being outside and in addition to the coolant radiator, thereby increasing the overall engine cooling capacity. I had not noticed that MY90 and newer had more complaints of low idle oil pressure. In my 89, I had an occasion where coolant temp was very near the redzone after a hard open road race in high desert heat, and the low oil pressure warning came on when I came to a stop at the end of the race. I've since been wanting to move my oil cooler out of the radiator to an external oil cooler.
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#8
I don't think the 90 and newer MY have BOTH an external cooler and radiator type. These models only have the external. If there's an oil line going into my radiator, I don't see it.
#9
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Parenthetically, 928s with automatic transmissions have both a sidetank (left side/passenger side US) and external cooler (in front of the radiator) in series. Even with the external cooler, the left side tank is the one that leaks most often. It's on the hotter (coolant entrance) side of the radiator and the hot ATF doesn't help. The oil cooler sidetank on the other (cooler) side is almost trouble-free, but I would rather have the MY90+ setup and maybe relocated trans cooling.
#10
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Nope, they don't. Bill's saying that having the oil cooling circuit outside the physical radiator increases the overall heat transfer capacity. Dunno if a 90+ radiator has extra cooling tubes for engine coolant where the oil cooler would have been, but if so, then perhaps the external oil cooler also allows a 'bigger' radiator, in the sense of surface area for conducting heat out of the antifreeze.
EDIT: What Bill said.
EDIT: What Bill said.