oil coolers

formulator

New member
Hi there

Im installing oil coolers on my 2008 Formula 292 Fastech twin mercury marine mx 6.2 377 sb they been great little stout engines but 4.5 quarts after running hard on a hot summer day, makes me a little nervous., oil psi is fine 40psi when cold and warm. but merc could have given this little beast one more quart , so im instaling oil coolers and oil temp sensors , hardin marine temp gauge which will be connected to a on off on toggle switch for reading port and starboard engines temps, talked to Rick at cpperformance which he was the best help and fast delivery not to mention knowledgeable, My Question is such ... is the oil cooler a good place to install a adapter for the sensor on the out line of the cooler . or does it need to be closer to the engine oil pan return , any advice or experience would be much appreciated thanks aka FORMULATOR
 
Hi Formulator,
Welcome to the forum.

I have a few thoughts having added oil coolers to my big blocks. It sounds like you are describing an inline oil temp sender adapter. This would mean more fittings and possible failure points in your oil lines. Preferred would be a threaded location in the pan, or on a remote oil filter housing, etc. The less fittings the better. Plus, I would think you'd want a temp closer to the crankcase. If no other options are available, I'd rather get what I can get temp monitoring wise.
Another thought that always comes to mind is beware of AN fitting sizes and true ID diameters. Be sure not to place smaller ID fittings or connectors in the system. They will restrict flow. Make sure you are maintaining your inside diameter throughout, regardless of whether everything "fits" together.
You didn't mention thermostats to bring the coolers into or out of the loop. Depending on where you live and boat, that could be an issue or not. I do not have them in my boat right now. I am a fair weather/warm weather boater. Cold weather boating, cool environment may make thermostats a good idea for best operating range. You don't want your oil too cool.
Finally, I wish you didn't have to share a gauge to manually switch back and forth to see what is up with the other engine. That might be a bigger pain than designing a solution to accommodate two gauges. That would be a bummer after all the rest of the work. I can't picture a 292 helm right now to see what is possible.
Good luck.
 
Thanks fund razor for the reply , ok sorry im not installing on my dash no no way to much work lol , just a little bracket with gauge and switch on port engine
just curious, clean little set up i guess, thanks for the heads up about thermostat , im not sure if my engines have one all ready from the factory ill check with my marine mechanic thats installing my coolers and lines will make it right for sure. I live in california so im not worried about cold temps not allowing my oil to heat up to proper operating range or condensation. thanks :USA:
 
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Thanks fund razor for the reply , ok sorry im not installing on my dash no no way to much work lol , just a little bracket with gauge and switch on port engine
just curious, clean little set up i guess, thanks for the heads up about thermostat , im not sure if my engines have one all ready from the factory ill check with my marine mechanic thats installing my coolers and lines will make it right for sure. I live in california so im not worried about cold temps not allowing my oil to heat up to proper operating range or condensation. thanks :USA:

The thermostat I am describing would be related only to the oil cooler "circuit" and act as a diverter to keep oil in the block if it is below a predetermined temperature. If your water is really cool, and your oil isn't as warm as you want, you don't want to supercool cold oil. Your mechanic will have good advice for your area of operation.
 
What they do at Skater on a new engine installation where the running parameters are unknown, is put a fitting at both ends of the oil cooler, then run the boat with two temporary oil temp gauges. That way we know what the temp cooler is doing. Oil temp in, oil temp out, log it, change the fitting to the other cooler and repeat.

It is the only way you can be positive the unit is doing its job properly.

Final temp is usually after. That is so if something happens to the cooler, tubes plugged from sand and seaweed, you know. Other say it should be prior, so you know if there is an engine problem. So in truth, it doesn't matter a ton, as long as you know what the cooler installed is doing to begin with.

And Fund is correct. You need it on both engines. If you can't, then make absolutely sure you have a working temp alarm light and buzzer on both.
 
Appreciated advice Ratickle & fund razor you too have giving great advice, ill keep it all in mind when we install in a couple of weeks. I have to say its been
a learing experience i was hoping to add a little more oil in the whole system ( meaning cooler and lines ) i didn't realize how important getting oil to a
good operating range was, i thought the engines would take care of raising the temperature by just running them. like i said 4.5 quarts isn't that much oil
when running hard on a hot day watching oil pressure come back up makes me nervous, my goal was to add more oil,cool it down when needed, thinking
i would be adding long jevity to these engines, fund ill check into if i need a thermostat for coolers size 2''x 16'' 1 1/4 hose rick at cpperformance said
this size would work great for my engine size and capacity no condensation issues i didn't think of asking him about thermostats ill find out soon enough.
Ratickle yes ill have sensors on both engines Thanks again u guys :beatdeadhorse5:
 
Hey Wheelinj !! thanks Oil cooler project came to a stop we tried to order stock transmission & oil coolers so the installation would be clean and easy. Sort of a plug-and-play job turns out I can't get the trans oil cooler that I need so I have a box with two new oil coolers gauge sending units in my garage on my shelf it was decided changing what is already in place for a small outcome wasn't cost effective the job labor parts $3500. Mercury Marine already figured out what works great with the 6.2 377 SB . Lesson learned don't buy parts until you do all your research sometimes it's better to leave things alone . So I'm just gonna run the hell out of these motors with clean oil . maybe someday I can step up to the blue motors but for now my 08 292 formula fast tech with small block motors is a awesome clean 70 mile an hour fine boat . So I'm going to relax Summers coming
 
:) Sounds like a good plan........

I would still accurately check temps to see if there is a possible issue.
 
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