11-12-2015, 02:02 PM
Ok Tiara lovers I have a follow-up post with more complete summary of my situation and am looking for input - help!
Need some help and clarity to an oil type & pressure issue I’ve been having with my pair of Crusader 454’s in my 98 Tiara 31. Early this year the oil pressure in my starboard engine dropped to 0. I was idling along and proceeded to stop & restart thinking / hoping it was a gauge or electrical issue. Sure enough the gauge read normal after restarting. Well, 10 min later it happened again, neither time did the oil pressure alarm sound. We got home carefully and following the guidance of a great Tiara Owner Forum I dug deeper. I swapped gauges and the problem persisted leading me deeper into the engine as the root cause. I proceed to change out the oil and filters with manual defined 5W-40 oil (note that the yard had done the preseason oil – filter change), and the problem seemed to go away. Well again the problem showed up a little later, but more as a less abrupt, up – down issue, meaning the pressure on the gauge would fall to 0-10 PSI for a time and then rebound to more normal, only to reoccur occasionally and randomly. Now, I’ve got the port engine (without any drop out pressure issues) running 50-70 PSI and the starboard engine running 40-50 PSI and occasionally dropping or running down to 0-10 PSI for minutes at a time (variance depending on running RPM’s). The normal PSI spread is a pretty big differential, isn’t it? What could be causing this? Should I worry? Did the yard gunk me up with bad or the wrong oil?
I’ve checked for leaks and all, and the bilges are clear. Oil levels are ok and the oil & filters have been changes 2x now as well, and last season’s oil analysis was perfect.
Also, my 4 wheel gear head have advised that I use 5W-40 diesel engine oil as it has zinc in it and is better aligned with the vintage engine blocks of my older 454’s. Presumably, the zinc takes the place of the lead in the cylinders that has been excluded from the now lead free gas. Is this true and or does it add any value or do any harm?
Need some help and clarity to an oil type & pressure issue I’ve been having with my pair of Crusader 454’s in my 98 Tiara 31. Early this year the oil pressure in my starboard engine dropped to 0. I was idling along and proceeded to stop & restart thinking / hoping it was a gauge or electrical issue. Sure enough the gauge read normal after restarting. Well, 10 min later it happened again, neither time did the oil pressure alarm sound. We got home carefully and following the guidance of a great Tiara Owner Forum I dug deeper. I swapped gauges and the problem persisted leading me deeper into the engine as the root cause. I proceed to change out the oil and filters with manual defined 5W-40 oil (note that the yard had done the preseason oil – filter change), and the problem seemed to go away. Well again the problem showed up a little later, but more as a less abrupt, up – down issue, meaning the pressure on the gauge would fall to 0-10 PSI for a time and then rebound to more normal, only to reoccur occasionally and randomly. Now, I’ve got the port engine (without any drop out pressure issues) running 50-70 PSI and the starboard engine running 40-50 PSI and occasionally dropping or running down to 0-10 PSI for minutes at a time (variance depending on running RPM’s). The normal PSI spread is a pretty big differential, isn’t it? What could be causing this? Should I worry? Did the yard gunk me up with bad or the wrong oil?
I’ve checked for leaks and all, and the bilges are clear. Oil levels are ok and the oil & filters have been changes 2x now as well, and last season’s oil analysis was perfect.
Also, my 4 wheel gear head have advised that I use 5W-40 diesel engine oil as it has zinc in it and is better aligned with the vintage engine blocks of my older 454’s. Presumably, the zinc takes the place of the lead in the cylinders that has been excluded from the now lead free gas. Is this true and or does it add any value or do any harm?
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