Why no oil cooler 350 mag MPI
 

Makes no sense, even on a tow boat under strain could benefit.
My oil gets 180 or so is this too much?
Causes oil pressure to drop after a hard run, what is too low until oil cools back down to regular operating temps?


LC

Because to burn off condensation in the motor oil as internally the motor needs to reach 212 degrees at some point while running. Condensation forms from internally combustion process. The small block and V-6 and 4 bangers do not run internally as hot (when properly cooled) compared to the big blocks. Also very cool motor oil DOES NOT flow as well.

A motor oil cooler for these apps most likely would run too cool temps unless it was bypassed a lot. Also adding oil bypass and oil t-stat along with plumbing to these lower hp engines will add to the price of them passed on to the end user. The OEM has to design / engineer and keep pricing somewhat in line so this stuff sells more so to the average boater.

Can you tell me how low is to low on oil pressure. I could almost swear that merc says min idle oil psi is 5.

merc spec is 4 psi at their recommend idle spec of 600 or 650 rpms. I think that is nuts. The old basic thru GM was 10 psi for every 1000 rpms. Again old rule of thumb that a lot still go by.

my bad I just looked it up thru the OEM Merc since I had it front of me. spec is 600 rpm with a minimum 6 psi of oil pressure in neutral at idle. correct idle speed in N is 600 rpms. Then their next spec listed is 2000 rpms min. oil psi 18 psi.

this was for sterndrives engine serial # 0M087348 and above

post your engine serial # if does not fall in this range and I can tell u exact what it is thru their spec. I know some merc engine specs were rated at 4 psi MIN. @ correct idle speed.

I know I am an 0M08XXXXXXX

So we are good to go on that info. I just had a scare this weekend, Little below 20 PSI at N after a hard run. Shut down and opened hatch, checked oil level, all good there, Fired back up light was red on gauge, shut back down, we are talking less than 3 seconds. Fired back up about 5 min later oil up at 20-25 psi, going to 40-45 instantly upon advancing throttle to 3k on tach. But I touched the oil filter when all this was happening and I thought damm that is too hot, but if it needs 212 to bake off condensation I am under that by feel. This is what prompted the question. Thanks for the Info BUP!

No problem - heck I talk boats all day long everyday, today I'm being lazy. Also too low / or no oil pressure you will get a alarm. It will be a critical alarm (non stop) continuous warning horn and your engine will go into guardian mode or shut down completely. I understand alarm is warning at that timeframe so its better to catch it before low / no oil pressure ever happens.

Even Carb motors for merc will do the same as for a warning horn about low / no oil pressure including the 4 bangers as well except without putting the engine into guardian mode = carb engines..

Next bring a hand held temp gun with U next time out to shoot oil temps at the pan and filter to see what it reads. also read what your water temps are at the t-stat and housing. It has 160 degree t-stat so 155 to close to 175 is normal op water running temps.

My 6.2s used to do that,switched to the Mercury semi synthetic. Always had more oil pressure after hard run.

I use mobile 1 delvac super to aide in oil breakdown due to no coolers. I also put in lucas oil stabilizer and this works great keeping pressure up but it think it looses its ability to keep the viscosity up in short time. We have only logged 25 hrs so far so it may be time to go with merc semi syn and see if that helps.

Try switching to a straight weight oil. I run 40W Valvoline racing oil. Mineral oil now until I feel my rings are completely seated than I will switch to a synthetic 40wt.