How low is too low for safe oil temp. I added a oil temp gauge this year and found out my oil temp was only about 120 degrees. Water temp is 160 degrees. I swapped the Auto Meter gauges from water to oil, same temps, they use the same sender. I have a 496 stroker about 600HP. Filter pad has center valve removed, side valve plugged, canton racing filter adapter, 3x18 oil cooler, Hamburgers filter housing. After seeing the low temps I added a Canton racing oil thermostat, still have low temps. I ordered a laser IR handheld thermometer and will see if I can get more information from that. I am checking the temp on the inlet to the filter after the thermostat.

Recirculating pump or crossover ? Crossover I’m betting

Yep, crossover works well, water temps do not fluctuate. Oil temp is my problem, maybe a defective thermostat? Cannot get much help from Canton Racing, guess I am going to have to call them back again.

Is this idling on the trailer or in the water with a good load on the eng?
Idling on the trailer my oil temp never really comes up much. Once running on the water with a load, it comes up ~200 degs.

Good question. After running all day does not get over 120.

Getting readings from an external temp gun would definitely be the next step.

Where is the oil temp sensor mounted amongst all the aftermarket oil sys components? Is it possible that it's air-bound?
My experience is that liquid temp sensors don't read air temp very well.

Handheld temp gun just came in today, I will test it out over Labor Day weekend. Sensor is in a -12 AN gauge adapter attached to the filter housing coming from the thermostat assembly.

UPDATE, oil temp was not low. AN anodized aluminum fittings do not conduct and a ground is needed for the sensors. Handheld temp gauge shows pretty normal temps on the AN fittings, actual oil temp is probably a little higher. I will have the gauges working for the next water test.

Good find. Have run into that with snodized parts too.

I use a flat male spade connector hose clamped to sensor’s brass hex body, to attach a thin ground wire.

You an also try to find a two wire temp sendor that reads in exact ohms you need. On 2 wire senders, 1 wire is sense, other is ground.

I am going to use stainless washers and sandwich a ring terminal. Auto Meter senders all came with a 1 wire hookup. I will report back in a couple weeks after I run it on the water.