My new to me boat has a 1998 Merc. 502 Mag with side mounted Whipple Supercharger. Engine is in the OL serial number range. Motor has standard Mercury style cooling system. Engine temperature is very cold, so I assume there is no thermostat in the engine. My question is there supposed to be a thermostat or not, if so what temp. If the Whipple doesn't use a thermostat what are you guy's running to get some engine and oil temperature

Factory 502 mag mpi is 160*

I had the same setup and started by gutting a tstat then made a washer that helped some but they do run cool .........make sure to check the oil in the compressor and change the back bearings if in doubt of service.

Let's get together on the water soon.

I run cp perf. 120° hi flow thermostats(couple of 3/16"th holes drilled in,new ones I believe don't need this done) and a thermostatically controlled oil cooler,water temp around 130° and oil temp 190°.oil system plumbed w/ -12 lines and fittings.

I have a m1 procharger on my 502 merc. It also runs cool.

Whipple recommends running a cold block with no water T stat. If you want warmer oil, you will need an oil thermostat to control how much goes thru the cooler. Call Young Performance, Eddie is the side mount ninja master.

Just got finished with a sidemount Whipple on an engine built to 500 EFI specs. Whipple states NO Thermostat in the several versions of the sidemount install instructions and that has worked well for us. Be sure to check water pressure in the block, want more than 15 and no more than 30 at WOT. Also upgrading the oil cooler to a 500 EFI unit or aftermarket unit with a oil thermostat is a great idea, gets the oil hot quick even though that engine cooling is 110 or so. Believe me, that engine makes plenty of heat even with no t-stat

Thanks for all the replies. My questions have been answers. I don't do much boating these days so, I'll leave it as it's is this summer and redo oil cooler with thermostat controlled this fall. I did change supercharger oil when I got the boat last fall and it was clean. Water pressure gauge is hooked to block and pressure reading are good. The dip stick on the whipple is in a hard spot to get so I took a pice of 1/8" steel that fits in the dip stick slot and welded a nut to the top. Makes a nice tool to remove dip stick with a wrench instead of chewing it up with screw driver. If anyone wants a picture of tool PM me with email,and I'll send picture.