hi all, am hoping the collective brain can help with troubleshooting. IO360A1A, 1300 SMOH, have been experiencing fluctuating oil px, which i realize many have in various forms, and have read through some of the posts here. I have 2 issues, one is the widly fluctuating pressure doing acro, specifically from inverted back to upright and a general low reading. I Flew monday 3 times around the patch, oil pressure was from 60 down to 20 and all places in between. Oil level has no apparant affect(7 qts). today hooked up another external gauge, same readings. upon cold start (95 f ambient) at 1200 rpm, oil px is 60 and if throttle pulled back to idle oil px drops to 40. pulled Oil px relief valve, no trash under ball. cleaned and reinstalled. adjusted oil pressure up but no matter how much i adjusted the px , the engine acted the same. adjusted to 'max, start at 1200 -again 60 psi, and idle 40 psi, so first question is why does the adjustment have no effect on oil px ??. I then moved onto vernitherm. i have the Air Wolf external filter, with both lines coming form the temp bulb/verniitherm housing. after much cursing and dissasembly, got the vernitherm off and i am perplexed. i thought the vernitherm had to 'seat' on the back of the case and when oil temp reached a given value, it opened and allowed oil to pass through, well the vernitherm is in the housing that is plumbed to the external filter and back again. The 2 oil coolers are plumbed in parallel from the back of the case, through the rear baffle cooler, down to the main cooler, and back to the case, so i dont see the point of the vernitherm being needed for an external filter. the vernitherm does not even reach the end of the housing, so there is no way it contacted the flange. What do you think could be my issue ? the Lycoming parts book lists 5 different springs as choices for oil px relief valve, then sends you to ssp 1776 as a reference for identifying the correct spring, but this just lists free length of springs, co i can not as of yet conclusively identify what spring i should have. Also forgot to say, oil pressure follows the throttle.
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