Oil Cooler Question
10-05-2023 | 12:05 PM
#11
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From: SW Ohio
Very insightful....
We know that any power adder puts additional pressure on the bearings and heat into the block, which inevitably leads to increased oil temps. I am seeing indicators that would support that suspicion. Being that it is an otherwise mechanically stock Merc 496HO, with a ProCharger, my layman's assumption is that the OEM oil cooler is just not quite getting the job done, and I'm exploring options to rectify it.
For the record, I have been known to stare at my dash, trying to figure out where I'd place an oil temp gage. I don't dismiss the potential need for one.
Thanks. Brad.
10-05-2023 | 03:17 PM
#12
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From: Omaha/LOTO
Griff,
I am running a 165° stat, and the temp holds at that as long as I run, no matter how hard. After a mild cruise, say 20min @3500RPM, if I settle in, down to an idle, the temp will climb to ~180° or so for 5-10min, then gradually come back down. The oil pressure does drop during this time, but usually only after I've run it harder than about 4K. These observations leads me to believe the oil is getting hotter than I'd think it should be. I had a 140° stat, that I got from Whipple when I had them do the stage 2 ECM tune, but, like a dumbass, I had it sitting on the swim deck, forgot about it, and donated it to the highway somewhere between my shop and our local lake
. It is my intention to acquire another, but have yet to do so. I can't imagine this will have any other affect, other than to lower the range in which these temperature swings take place. How much effect does coolant temp have on oil temp?
Thanks. Brad.
I am running a 165° stat, and the temp holds at that as long as I run, no matter how hard. After a mild cruise, say 20min @3500RPM, if I settle in, down to an idle, the temp will climb to ~180° or so for 5-10min, then gradually come back down. The oil pressure does drop during this time, but usually only after I've run it harder than about 4K. These observations leads me to believe the oil is getting hotter than I'd think it should be. I had a 140° stat, that I got from Whipple when I had them do the stage 2 ECM tune, but, like a dumbass, I had it sitting on the swim deck, forgot about it, and donated it to the highway somewhere between my shop and our local lake
. It is my intention to acquire another, but have yet to do so. I can't imagine this will have any other affect, other than to lower the range in which these temperature swings take place. How much effect does coolant temp have on oil temp?Thanks. Brad.
10-05-2023 | 03:27 PM
#13
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From: SW Ohio
10-05-2023 | 06:13 PM
#14
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I had a 100% stock 496. I drove it easy most of the time. The longest I had it wot was about 2 minutes. Oil temp was climbing to 240 plus. That's when I backed out down. Water temp was around 70*.
If you drive the engine hard, the oil will definitely be hotter with the blower.
Larger oil cooler depends on your driving habits.
If you drive the engine hard, the oil will definitely be hotter with the blower.
Larger oil cooler depends on your driving habits.
10-06-2023 | 07:16 AM
#15
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From: Grand Haven, MI
I would never buy a used oil cooler, you just never know what has been through it. You really need to figure out what your oil temp is, basing it off oil pressure isn't very accurate. For reference, my water temp is around 160 and oil is 190
10-06-2023 | 09:11 AM
#17
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From: Portland OR
I've built a few 496s with whipple superchargers. I've done some experimentation on oil coolers. I went through 5 different sizes just testing etc. So, I did try it with just the factory oil cooler as a baseline. The oil temp shot up to 250+ faster than Biden's deficit. (measured before the cooler) The rate of climb was scary. At the 600-650hp level a 3x16 CP Performance cooler worked just fine. On an 800hp 496HO it's looking like a 13 plate box cooler is the trick. Hope that helps.
10-06-2023 | 09:19 AM
#18
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From: Central IL
I've built a few 496s with whipple superchargers. I've done some experimentation on oil coolers. I went through 5 different sizes just testing etc. So, I did try it with just the factory oil cooler as a baseline. The oil temp shot up to 250+ faster than Biden's deficit. (measured before the cooler) The rate of climb was scary. At the 600-650hp level a 3x16 CP Performance cooler worked just fine. On an 800hp 496HO it's looking like a 13 plate box cooler is the trick. Hope that helps.
10-06-2023 | 09:26 AM
#19
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From: Lake George
Rule of thumb is 10psi per 1000rpm so 20 at an idle is not out of the ordinary for hot oil. My engine once warm has 25 at 800rpm and 65 at 6000rpm. Any more than that you'll start to have distributor gear fatigue. I understand you have coil packs on a 496, but its just a big block rule to keep in mind.
I 10000% agree on never ever ever buy a used oil cooler. They aren't that expensive. If the $200 you're going to save makes it feasible, a less expensive hobby is in order.
You may very well need better oil control. But a used cooler isnt the route I would take.
I 10000% agree on never ever ever buy a used oil cooler. They aren't that expensive. If the $200 you're going to save makes it feasible, a less expensive hobby is in order.
You may very well need better oil control. But a used cooler isnt the route I would take.
10-09-2023 | 07:59 AM
#20
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From: SW Ohio
Rule of thumb is 10psi per 1000rpm so 20 at an idle is not out of the ordinary for hot oil. My engine once warm has 25 at 800rpm and 65 at 6000rpm. Any more than that you'll start to have distributor gear fatigue. I understand you have coil packs on a 496, but its just a big block rule to keep in mind.
I 10000% agree on never ever ever buy a used oil cooler. They aren't that expensive. If the $200 you're going to save makes it feasible, a less expensive hobby is in order.
You may very well need better oil control. But a used cooler isnt the route I would take.
I 10000% agree on never ever ever buy a used oil cooler. They aren't that expensive. If the $200 you're going to save makes it feasible, a less expensive hobby is in order.
You may very well need better oil control. But a used cooler isnt the route I would take.
I guess the thing that caught my attention is that it stays at ~40lbs at idle, even after coming up to temp (water), so long as I stay at idle, but, then, after cruising is when it drops off when back at idle. Maybe I'm overthinking it. I've been accused before....
Loud and clear on the used oil cooler. I was a bit concerned about the potential implications of it. I won't.
My real concern with dropping oil pressure is the correlation with oil temp. I know that hot oil is oil breaking down. I just don't know what that threshold is or how hot it's actually getting.
Thanks. Brad.
