Oil pressure dropping under load after oil change...
10-17-2011, 08:26 AM
#21
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Finally took my engine apart. All the bearings looked like the above picture excpet the bottom half of the thrust bearing and the bottom half of #4. They were completely wiped out with no coating left on the bearing. The only explanation for this could be the McLeod clutch I was running. It was way too tall(stack height of twin) causing too much load on crank.
10-17-2011, 11:56 PM
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Finally took my engine apart. All the bearings looked like the above picture excpet the bottom half of the thrust bearing and the bottom half of #4. They were completely wiped out with no coating left on the bearing. The only explanation for this could be the McLeod clutch I was running. It was way too tall(stack height of twin) causing too much load on crank.
10-18-2011, 11:55 AM
#23
Finally took my engine apart. All the bearings looked like the above picture excpet the bottom half of the thrust bearing and the bottom half of #4. They were completely wiped out with no coating left on the bearing. The only explanation for this could be the McLeod clutch I was running. It was way too tall(stack height of twin) causing too much load on crank.
10-18-2011, 12:51 PM
#24
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Finally took my engine apart. All the bearings looked like the above picture excpet the bottom half of the thrust bearing and the bottom half of #4. They were completely wiped out with no coating left on the bearing. The only explanation for this could be the McLeod clutch I was running. It was way too tall(stack height of twin) causing too much load on crank.
And also if this was the case, the clutch being partially depressed all the time would likely have slipped.
And for all the pressure it would be placing even if partially in contact, I doubt it would hurt the thrusts much at all. If it was in more contact, the clutch would have to be slipping, unless the engine makes no power at all.
10-18-2011, 05:19 PM
#25
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Check the crank for a bend. Also make sure to get the cap and line bore checked. My crank was bent .006 and my cap was damaged. Engine builder thinks that the cap walked on me due to using the stock main studs. I had a black lower half on the #4 bearing on mine.
The lower halves on both mains were the ones completely copper. The crank is going in the trash since im building a sleeved 434ci NA motor with an LS7 top end. Im only reusing the block and rods...which were undamaged. The block is being checked at ERL before they sleeve to make sure everything is good.
10-18-2011, 05:23 PM
#26
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Surely that would have been blatantly obvious when fitting the engine to the gearbox ?
And also if this was the case, the clutch being partially depressed all the time would likely have slipped.
And for all the pressure it would be placing even if partially in contact, I doubt it would hurt the thrusts much at all. If it was in more contact, the clutch would have to be slipping, unless the engine makes no power at all.
And also if this was the case, the clutch being partially depressed all the time would likely have slipped.
And for all the pressure it would be placing even if partially in contact, I doubt it would hurt the thrusts much at all. If it was in more contact, the clutch would have to be slipping, unless the engine makes no power at all.
10-18-2011, 05:43 PM
#27
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A worn thrust bearing will not affect oil pressure as they only rely on spent oil from the main bearing anyway. And I dont see how a worn thrust bearing will cause main bearing failure.
10-18-2011, 06:48 PM
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That's not true. A worn thrust bearing will do exactly what my car did. As you put load on the motor, it pushes the crank forward(and opens up on the thrust bearing relieving pressure) and caused the pressure to drop as the load increased. And the thrust is #3, and as my engine builder stated ,when one bearing goes out, it usually takes the next one out as well.
Last edited by Snyper; 10-18-2011 at 06:56 PM.
08-20-2023, 11:08 AM
#30
That's not true. A worn thrust bearing will do exactly what my car did. As you put load on the motor, it pushes the crank forward(and opens up on the thrust bearing relieving pressure) and caused the pressure to drop as the load increased. And the thrust is #3, and as my engine builder stated ,when one bearing goes out, it usually takes the next one out as well.
