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Message: That's bad logic as i explained already - but will again, more slowly
Changed By: grant
Change Date: October 03, 2014 01:12PM
That's bad logic as i explained already - but will again, more slowly
Change Date: October 03, 2014 01:12PM
That's bad logic as i explained already - but will again, more slowly
proves nothing. Parts swapping is not diagnosis.
Let's back up and address the issue.
The assertion is that the DOF drew sufficient oil to affect the performance of the variocam mechanism. Correct? No other assertion makes much sense.
If this is true, then we MUST assume that there is insufficient headroom above the maximum flow rate to a) oil the car, b) drive variocam and c) drive the DOF, all simultaneously.
If true under normal circumstances this would affect 100% of DOF equipped cars. It does not.
So what is different about this car? There are 4 possibilities:
1. the DOF was not installed properly (how i cannot say)
2. the oil pump or local passageway restricts flow at pressure X so that it cannot deliver the volume other cars do
3. The motor draws more oil than expected, using up the flow needed by the VC and DOF
4. The variocam requires more oil or pressure than normal, for unknown reasons
There are no other explanations that fit all facts.
The most basic numbers to know are the oil pressure and flow. They could tell us if the motor has low pressure due to, for example, bearing wear (a normal issue with high age motors) or due to a poor pump or, blocked passages (typically high pressure before the blockage and low after).
You don't appear to know those. You were not paid to measure those, i realize, but without them you cant really say anything at all.
The issue i raised, as did others, is that you DID draw a conclusion, without the needed facts.
You said then, and re-iterated here, that swapping the part proves it is the fault. Not even close to true.
I think you should acknowledge that. we cant expect more from you than that. We'd love data, but someone has to pay you to make the tests, so we cannot expect it.
but we can expect that you dont claim things that are not substantiated by what you know.
Grant
Let's back up and address the issue.
The assertion is that the DOF drew sufficient oil to affect the performance of the variocam mechanism. Correct? No other assertion makes much sense.
If this is true, then we MUST assume that there is insufficient headroom above the maximum flow rate to a) oil the car, b) drive variocam and c) drive the DOF, all simultaneously.
If true under normal circumstances this would affect 100% of DOF equipped cars. It does not.
So what is different about this car? There are 4 possibilities:
1. the DOF was not installed properly (how i cannot say)
2. the oil pump or local passageway restricts flow at pressure X so that it cannot deliver the volume other cars do
3. The motor draws more oil than expected, using up the flow needed by the VC and DOF
4. The variocam requires more oil or pressure than normal, for unknown reasons
There are no other explanations that fit all facts.
The most basic numbers to know are the oil pressure and flow. They could tell us if the motor has low pressure due to, for example, bearing wear (a normal issue with high age motors) or due to a poor pump or, blocked passages (typically high pressure before the blockage and low after).
You don't appear to know those. You were not paid to measure those, i realize, but without them you cant really say anything at all.
The issue i raised, as did others, is that you DID draw a conclusion, without the needed facts.
You said then, and re-iterated here, that swapping the part proves it is the fault. Not even close to true.
I think you should acknowledge that. we cant expect more from you than that. We'd love data, but someone has to pay you to make the tests, so we cannot expect it.
but we can expect that you dont claim things that are not substantiated by what you know.
Grant
Original Message
Author: grantDate: October 03, 2014 12:56PM
That's bad logic as i explained already
proves nothing. Parts swapping is not diagnosis.
Grant
Grant