Tomcats correct, all holes in the block itself are cooled oil.
Also sorry if it got a little OT. I tried to keep it just pertaining mainly to the original topic. But looks like some good came out of it as we both are flowing backwards and our motors are the exact same setup, 'cept for MK4 vs GenV.

US1 out!
;)

My 1995 Merc Mk V 454 has a (plugged) 1/4"NPT bung welded to the middle of the port side of the stock 8 qt oil pan (below and aft the motor mount).
It's a little above the oil level but the hot oil runs across it on the way to the bottom of the pan.

Just a note, my stock cast aluminum Mercruiser oil pan has a 3/8"NPT for the drain plug on the starboard side. I use this for the oil temp. sender and pump out the oil through the dipstick tube that Merc. tapped into the pan bottom port side. Love that male garden hose fitting they use.

SF Ocean... What kind of temperature readings are you getting at the drain plug location? This is where I was planning to install the senders, but an worried about oil leaks. Have you had any problem with leaks?

Does anyone have an opinion on putting the sender in the drain plug hole as opposed to in the oil filter adapter? I could go either way, but need good advise now while the engines drain plugs are still accessible. Once I put the SB engine back in, I cannot remove or install the senders if I install them in the drain plugs. That fact makes me partial to installing in the oil filter adapter. Please advise!

BT

Here is the compresion fitting I used, and the $29.oo digital thermometer. I mounted in the oil filter housing.

NPT to Compretion fitting

Thermometer:The nice thing about this thermometer is, It's got a High/Low temp. recall. and after you install it. You can bend and conform it to your liking.

Digital Thermostat

[ 02-10-2002: Message edited by: Kanookstr ]

Kanookstr... what kind of readings do you get at your oil filter adapter and what engine?

BT

Blue Thunder, I run a procharged 502 Mag MPI. My oil is running 240ºF. sometimes after a really hard run, she reaches 270ºF. But the range should be,
Above 212ºF, but below 280ºF
Good luck. ;)

[ 02-11-2002: Message edited by: Kanookstr ]