250 Optimax Pro Xs oil leak

[521 Fishing]

2017 Pro XS
Serial number 2B363006
Model 1251P73BD
3 blade Fury 24p (I think)
Wot 5650 72mph
Mercury vesselview

Hey Guys,

After my last outing I noticed a very large amount of oil coming out of lower cowling of my motor. I took good off and oil was everywhere. After reading about oil leaks I check the oil pump and it was bone dry. All oil on port side. Seems to be from reservoir best I can tell. I checked the cap and it was rather loose. If I change the reservoir can I prime by using compressed air into remote fill until oil runs out engine reservoir? Gas a $6 a gallon has us all desperate. I greatly appreciate you help and your time.

ps if there is something else I should check for oil leak let me know. I degreased engine and ordered leak glasses and UV light. But feel like it was the reservoir bc of oil being all over port side. (No oil present around compressor)

[SilverFox579]

If you replace the engine reservoir an oil pump prime sequence is required. Unless you have Diacom diagnostics software you'll need to have the prime sequence performed by a Mercury dealer.

[Bob G.]

Can get an UV light at an automotive store for detecting Mercury DFI oil.

[EuropeanAM]

If the reservoir cap was loose, you can be GUARANTEED that you found the leak.

Tank replacement DOES require oil pump prime. NEVER, EVER use shop air to pressurize the remote oil tank- you will explode the remote tank and coat every square inch of the bildge in oil.

Service Manual describes using a gearcase-pressure-tester (hand operated) at about 6 psi to bleed air from the engine-mounted tank (this is NOT the same as the oil pump prime, however).

One final note: That particular oil tank has been on backorder for MONTHS. I know it's not the news you want... but you may not find one for a while.

[521 Fishing]

If I maintain my oil levels can I use my boat while I wait. It may be fine since I tightened but haven’t had a chance to verify.

[EuropeanAM]

Provided that it doesn't leak- yes. Note that even the slightest leak at the oil cap will result in a LOT of oil.

I don't recommend trying to "patch" things, but I've seen a few tanks where the owner applied a little bit of teflon tape and somehow managed to get it to stay tight. Not what I recommend- but when there are no parts available....

[521 Fishing]

As always. I greatly appreciate all of your help. I have worked in the auto repair industry all my life and have NEVER encountered a tech so willing to provide help free of charge. I’m in NC and wouldn’t hesitate to drive to you Don. You are a gentleman and a scholar.