Low Oil Temp
09-25-2021, 10:09 AM
#21
Registered
Thread Starter
Just some notes on oil temps. Don't be scared to run the oil temp up a little. Would like about 215 or 225 ish. A little higher not an issue. Burns water out better. Most engines run the oil too cool.
I just took the oil cooler off to try it because mine(MPI) ran 180 to 220 ish even in hot summer. Friend of mine's carbureted 502's run with no cooler and runs around 220 to 250 ish when running hard in hot summer. Thus trying mine without cooler. Cleanest motors i have ever seen have been run their lives with quite a bit hotter oil.
I called Shell Rotella today and their upper level tech department said their 15W40 oil can take 300 F for a typical summer's usage without any issues. Interesting talk.
I just took the oil cooler off to try it because mine(MPI) ran 180 to 220 ish even in hot summer. Friend of mine's carbureted 502's run with no cooler and runs around 220 to 250 ish when running hard in hot summer. Thus trying mine without cooler. Cleanest motors i have ever seen have been run their lives with quite a bit hotter oil.
I called Shell Rotella today and their upper level tech department said their 15W40 oil can take 300 F for a typical summer's usage without any issues. Interesting talk.
The following users liked this post:
Cap'm Kurt (09-30-2021)
09-27-2021, 09:19 AM
#22
Registered
I run Amsoil 15w-50 racing oil and Amsoil techs told me their oil can handle 300 degrees no problem. I have a small cooler and my oil runs 280 after running hard for any distance. My oil comes out clean and it's still hard to see on the dipstick, when I change it. There is a new oil spec now that requires oil to be run in a test engine at 300 degrees for an extended period and then the engine is tested for wear and the oil is tested for viscosity breakdown. Amsoil ran the test with their signature oil and when they shut down and tested everything there was almost no change in the oil and no visible wear. So they put the engine back together and put the oil back in and ran it a second time. The oil still passed the test after running double the hours. The lab techs at the testing firm couldn't believe it. I also ran into the grounding issue, you have to go easy on the thread sealer so you get a good ground. I put my sensor right where the oil enters the filter before it goes into the cooler. I double checked it with my temp gun and it's accurate. My oil in my tow vehicle barely hits the thermostat temp even when towing, but it stays there for hours so moisture isn't an issue.
The following users liked this post:
Cap'm Kurt (09-30-2021)
09-28-2021, 01:36 PM
#23
Registered
Thread Starter
I run Amsoil 15w-50 racing oil and Amsoil techs told me their oil can handle 300 degrees no problem. I have a small cooler and my oil runs 280 after running hard for any distance. My oil comes out clean and it's still hard to see on the dipstick, when I change it. There is a new oil spec now that requires oil to be run in a test engine at 300 degrees for an extended period and then the engine is tested for wear and the oil is tested for viscosity breakdown. Amsoil ran the test with their signature oil and when they shut down and tested everything there was almost no change in the oil and no visible wear. So they put the engine back together and put the oil back in and ran it a second time. The oil still passed the test after running double the hours. The lab techs at the testing firm couldn't believe it. I also ran into the grounding issue, you have to go easy on the thread sealer so you get a good ground. I put my sensor right where the oil enters the filter before it goes into the cooler. I double checked it with my temp gun and it's accurate. My oil in my tow vehicle barely hits the thermostat temp even when towing, but it stays there for hours so moisture isn't an issue.
09-29-2021, 10:02 AM
#24
Registered
I have never tested the oil. I change my oil when I winterize so I have fresh oil in the motor over winter. I may put 25-50 hours on my oil depending on the season. My oil comes out just a little darker than I put it in and oil pressure doesn't vary from old oil to new so I'm not getting any breakdown. To be honest, I have been tempted to run my oil 2 seasons when I've had a short season. I keep my boat in a heated garage so the temp doesn't vary 20 degrees from winter to summer. The only problem I have with condensation is in the summer when it's super humid out. My garage is so well insulated it doesn't get over 70 degrees even in the summer when it's in the 90's. When I open the garage door the warm humid air hits the boat and it's soaking wet. I have to pull it out and towel it off. I may put a de-humidifier in the garage in the summer to keep it dry. I do run the Donaldson P550832 filter which is much larger than stock and has a 20 micron rating.
09-30-2021, 12:34 AM
#25
Registered
VIP Member
TIL,
I agree on the two season thing. Motor will never know it - oil is a little more forgiving than we realize. I've seen oil run for 3/4 years with no issues. I have run two short seasons a couple times but typically change it in the fall.. 50-60 hours/season. Funny thing is boaters all seem to have any number of other mechanical or moisture related issues with I/O motors rather than normally just wearing out, or oil issues. Very seldom see a worn out motor.
I agree on the two season thing. Motor will never know it - oil is a little more forgiving than we realize. I've seen oil run for 3/4 years with no issues. I have run two short seasons a couple times but typically change it in the fall.. 50-60 hours/season. Funny thing is boaters all seem to have any number of other mechanical or moisture related issues with I/O motors rather than normally just wearing out, or oil issues. Very seldom see a worn out motor.
09-30-2021, 12:39 AM
#26
Registered
VIP Member
I run Amsoil 15w-50 racing oil and Amsoil techs told me their oil can handle 300 degrees no problem. I have a small cooler and my oil runs 280 after running hard for any distance. My oil comes out clean and it's still hard to see on the dipstick, when I change it. There is a new oil spec now that requires oil to be run in a test engine at 300 degrees for an extended period and then the engine is tested for wear and the oil is tested for viscosity breakdown. Amsoil ran the test with their signature oil and when they shut down and tested everything there was almost no change in the oil and no visible wear. So they put the engine back together and put the oil back in and ran it a second time. The oil still passed the test after running double the hours. The lab techs at the testing firm couldn't believe it. I also ran into the grounding issue, you have to go easy on the thread sealer so you get a good ground. I put my sensor right where the oil enters the filter before it goes into the cooler. I double checked it with my temp gun and it's accurate. My oil in my tow vehicle barely hits the thermostat temp even when towing, but it stays there for hours so moisture isn't an issue.
BTW,
Your oil temps look to be where you'd want them. I just took off my oil coolers on my 502's to see what temps it will run. Was way to cool even in summer with the big oil coolers that came on these 502MPI's. Oil was brown, not just slightly blackish like you want it to be. We shall see.
10-04-2021, 07:15 PM
#27
Registered
Thread Starter
Oil analysis came back better. Raising the oil temps above 210 degrees definitely helps the oil. Other than a random high reading of Boron everything looked normal.
10-14-2021, 10:23 PM
#28
Registered
VIP Member
Jeffsway,
That's good news. Most don't realize their oil is running too cool. If i recall correctly, GM stated many years ago that a lot of wear comes from microscopic "pitting" from corrosion due to acids and of course moisture. Little wear compared to other factors comes from the motors when its up to temp and running. And moisture certainly makes the corrosion situation worse. :You've done good with the oil temps.
I would stick with the 15-40 diesel oil. I use 15w40. After hundreds of hours on the 502 motors, really no signs of cylinder wear. I do like the feeling of using a really good oil, but experience says the 15w40 diesel is good enough. And because so much cheaper, even though price of oil would not even be an issue if it helps engine life. But its not necessary. I actually use a brand called Schaeffer 15w40 diesel oil. More than Rotella but less than Amsoil. Used it for 30 years now. I bet you would never know the difference even using Rotella.
That's good news. Most don't realize their oil is running too cool. If i recall correctly, GM stated many years ago that a lot of wear comes from microscopic "pitting" from corrosion due to acids and of course moisture. Little wear compared to other factors comes from the motors when its up to temp and running. And moisture certainly makes the corrosion situation worse. :You've done good with the oil temps.
I would stick with the 15-40 diesel oil. I use 15w40. After hundreds of hours on the 502 motors, really no signs of cylinder wear. I do like the feeling of using a really good oil, but experience says the 15w40 diesel is good enough. And because so much cheaper, even though price of oil would not even be an issue if it helps engine life. But its not necessary. I actually use a brand called Schaeffer 15w40 diesel oil. More than Rotella but less than Amsoil. Used it for 30 years now. I bet you would never know the difference even using Rotella.
10-15-2021, 01:14 PM
#29
I went back and forth with AMSOIL technical support and they said 20W50 ARO or 20W50 ZRF. I ended up using ZRF with good oil analysis results after each oil change. If you want more details as to why, let me know and I’ll probably bore the hell out of everyone.
The following users liked this post:
jeffswav (05-18-2022)
