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low oil temp
Running a 31 scarab with twin 454s. When I got the boat the oil temp would climb up and get hot. I removed the cooler and cleaned. It was full of rocks sand and impeller parts. I went ahead and cleaned both engines. Now after cleaning the oil temp is very low. Pressure is fine but temp will hardly show up on the gauge. I know they are right because I can hold the oil filter with my hand. I know its winter here and the water temp is pretty low for florida. Is this going to harm anything?
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It will eventually start causing milky looking engine oil/cream cheese breathers because the oil isn't getting hot enough to steam off the condensation. I had this problem at one time and ended up adding oil tsats.
BT |
the first question is what was it when it was hot and what is it now?
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and do not forget OIls job is also to help cool internal engine parts as well so in return its going to get hot from grabbing heat.
Cold oil does not flow as well - IMO good oil temps 185 to 225 maybe 190 to 220 and it has to reach at some point 212 degrees for a bit to burn off the process of combustion inwhich is water vapor & condensation. Oils job and related parts also is to flow at the right volumes at the right place at the right times - |
Are you taking the temp before or after the cooler? My oil barely reaches 140°F after the cooler.
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Originally Posted by Rookie
(Post 4663940)
Are you taking the temp before or after the cooler? My oil barely reaches 140°F after the cooler.
What are you getting for oil temps after hard runs before cooler? |
Took it out tonight and after a hard run I was able to get 190 out of one engine. Other engine showed nothing. Felt the oil filters and they where about the same temp so looks like I need to trouble shoot an indicating problem. Pretty simple system I’ll get into that tomorrow. So when the water temp comes up everything should be good. Rookie it it takes the oil temp right at the oil filter housing so I would say before the cooler. |
Originally Posted by compedgemarine
(Post 4663930)
the first question is what was it when it was hot and what is it now?
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go buy a laser temp gun. they are pretty cheap and you can shoot each engine to see what they are running and how close to each other they really are. senders go bad all the time and even gauges depending on how old they are and what brand. if the laser gun shows them to be close to each other then all is good other than the sender or gauge.
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Originally Posted by getrdunn
(Post 4663963)
On my 496 engines I installed oil temp sender in pan and water in block off a T fitting. Just my preference. What are you getting for oil temps after hard runs before cooler? |
These are also nice to place on areas of concern.
https://www.ebay.com/itm/PAPER-THERM...tz4A:rk:4:pf:0 |
Originally Posted by Gunradd
(Post 4663967)
Took it out tonight and after a hard run I was able to get 190 out of one engine. Other engine showed nothing. Felt the oil filters and they where about the same temp so looks like I need to trouble shoot an indicating problem. Pretty simple system I’ll get into that tomorrow. So when the water temp comes up everything should be good. Rookie it it takes the oil temp right at the oil filter housing so I would say before the cooler. I have been told that the sender location you are using often does not read well. |
Originally Posted by Rookie
(Post 4663975)
I use to get around ~170 max on the Scarab with same engines and running 6000+RPM. I Had 2 senders 1 before and 1 after cooler, just toggled between senders. This is so I would know the delta before and after the cooler to see if it is doing it's a job and what the temperature of the oil that is being delivered to the bearings, I don't need t know how hot my oil pan gets. I run 160°F sandwich thermostats. I think it's a pretty sweet simple setup.
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Originally Posted by ph1971
(Post 4664006)
Wouldn’t the before cooler temp and the oil pan temp be very close to the same? My sender is currently in the pan. Should it be moved? Where is yours before the cooler? Thanks This is a hotly debated topic like which oil to use. I prefer to see what the oil temp is coming out of the engine (oil pan, pre cooler). I want to know how hot the oil is getting. If you had a sensor after that cooler that would be helpful to see how well the cooler is working. My sensor is mounted in the oil filter pad, works great. Just my. 02 |
Originally Posted by ph1971
(Post 4664006)
Wouldn’t the before cooler temp and the oil pan temp be very close to the same? My sender is currently in the pan. Should it be moved? Where is yours before the cooler? Thanks |
The good news is your temp problem is on the easy side to address. Too hot can be much more of a challenge. If you get the gauge working correctly and are still having low oil temps when sea temp is hot, one way you can raise oil temp easily is to raise engine water temp (assuming you have room). I suspect you will find your oil temps to be ok though. I personally like 190f after a run as long as no creamed cheese develops.
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Originally Posted by ph1971
(Post 4664006)
Wouldn’t the before cooler temp and the oil pan temp be very close to the same? My sender is currently in the pan. Should it be moved? Where is yours before the cooler? Thanks Going more of the redneck way, if you have good hot oil pressure and it doesn’t smell burnt then you’re good there. If you’re getting moisture in the valve covers then you need to adjust something. But I feel the most important duty of the gauge is tell you if something changes. If the oil is always at X temp and suddenly changes that’s the important data point more so than the actual number. |
Thanks guys. Trouble shot it today using hot cooking oil heated up to 200. Got nothing on the gauge. Grounded out the sensor wire and it went full hot. That told me it was the sensor. Picked up a new one and all is good now. Temp is still only about 190 but it’s cold water the boat normally does not see. Got a pic of the part number Incase anyone needs it from advanced auto. https://cimg3.ibsrv.net/gimg/www.off...a8306e7c4.jpeg |
Glad you figured things out Gunradd. Sorry I hijacked your thread with my question. Thanks to all that answered. Gunradd, I have Hardin Marine’s thermostatic block adapter, and it works great for getting the oil up to temp if you need to bring yours up. I am getting to 240* on a long hard run so a cooler upgrade is in my future. |
Originally Posted by ph1971
(Post 4664006)
Wouldn’t the before cooler temp and the oil pan temp be very close to the same? My sender is currently in the pan. Should it be moved? Where is yours before the cooler? Thanks https://www.ebay.com/itm/P194-10AN-F...aTak:rk:1:pf:0 |
Originally Posted by Gunradd
(Post 4664080)
Thanks guys. Trouble shot it today using hot cooking oil heated up to 200. Got nothing on the gauge. Grounded out the sensor wire and it went full hot. That told me it was the sensor. Picked up a new one and all is good now. Temp is still only about 190 but it’s cold water the boat normally does not see. Got a pic of the part number Incase anyone needs it from advanced auto. 190*F is a good oil temp. BTW; I walked across my cove today. Few guys out there sitting on buckets fishing. Your water is not cold. :) |
That’s a cool fitting Rookie, was not aware it existed. |
Originally Posted by ph1971
(Post 4664096)
That’s a cool fitting Rookie, was not aware it existed. |
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