Oil press drop on 496
 

While out for the first time this year the boat ran great until I was on my way back to the trailer. The oil pressure gauge was 60psi cruising at around 2200 rpm, when I accelerated the oil press started to drop rapidly going all the way to 0. When I drop back to 2200 rpm it comes back up to 60ish. The gauge was acting a little erratic and jumpy but never dropping down like it did on the way back. It is an electric gauge. I am going to see if I can find a mechanical gauge to hook up.
Any ideas?

If it really did drop back to 0 you would likely have a serious problem. I have seen electric senders act up as they warm up and as oil pressure went up, check it with a mechanical gauge first before you get excited about it. First time out this season maybe some corrosion on the terminal.

Also a silly question-suggestion, make sure the oil level is at the proper level in the engine??

Best Regards,
Ray @ Raylar

If you have a SmartCraft guage you can use it for comparison. If not, you can also use a scan tool to check/read the digital oil pressure sender to see if it give same reading.

I've now had two of the analog sending units fail. Talking about the one up on the back top of the block. Single wire going to it..

Thanks for the input guys. The oil level is good. Also it drops when just free reving. I'll work on getting a mech gauge.

Thanks again,

Tom

I am having the same problem with my 454 I think my pump is bad. Let me know what you find out.

Check your connection on the sender. If it were really going to zero the engine should alarm and go into guardian.

I bet it is bad sender. I have odd oil pressure, erratic, jumped around, read low then OK etc. Sender fixed it all.

I had exactly the same thing happen to me with the analog electric oil pressure gage. I also have a Smart Craft gage that can read oil pressure as recorded by the ECU. The Smart Craft gage said I had plenty of oil pressure and as Bob says if the ECU had detected zero oil pressure it would go into Guardian Mode. Check integrity of the electric oil pressure gage's wiring/connrections. I found the snap on wire connector socket at the sensor post to be less than tight. I tightened up the fit and no further problems.

I have had a number of senders do the exact same thing.