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[Entwood]

mmm can you explain to me how excess oil pump pressure works in a negative pressure void

The cam covers are an open void internally .. so oil pressure there would be non-existent under most circumstances .. as the crankcase is held at a partial vacuum , by the action of the breathers, then there is even less reason for such a happening !!!

Pumps don't produce pressure BTW ... they produce flow, the resistance to which is pressure - simple but basic physics.

There is a lot of data around - should you care to research it properly - regarding the use of oil flushes on old engines .... it can actually (and usually will ) do more harm than good.

You comments about the oil flush cleaning the pump, and the results being visible at the pump outlet are true ... as the pump is cleaned the flow will increase; the outlet is a fixed restriction and as such causes pressure, if the flow through a fixed orifice increases the pressure at that orifice will also increase.... again simple physics.

As already said .. the relevance of all that to cam cover gaskets is precisely ... ZERO

 

You can wish as much as you like .. but you can't change the laws of physics ...

[Brucie1946]

Thankyou for your reply entwood

You sound a very learned chap, an engineer perhaps?

I dont wish to explain any further, because I dont have a problem with the information given.

Feel free to contact the v6technicians if you need any further clarification.

Must go and walk the dog now!

[VXL V6]

My first 3.2 suffered with tappet noise and when tested with a pressure gauge it was suffereing pressure switch issues. The car was taken to Geoff and Pete (V6Technicians) who worked on the Ellesmere Port V6 Production line in all areas and know the engine inside out, they used an engine flush and the tappet noise was instantly resolved and the pressure was brought back down to within the original limits.

The advise they gave me was to change the oil regularly and run an engine flush through it every 12 months / 12K miles. I stick by that advice to this day. If you use the flush at regular intervals I see no issues, however I wouldn't use it on a high mileage engine that the history is unknown on.

So many 3.2's and 2.6's that i've heard suffer noisy top ends due to VX / GM's 20K - please the fleet manager - service regimes, unfortunately the bit people don't read is the 'OR ONE YEAR' statement.
 

[VXL V6]

You comments about the oil flush cleaning the pump, and the results being visible at the pump outlet are true ... as the pump is cleaned the flow will increase; the outlet is a fixed restriction and as such causes pressure, if the flow through a fixed orifice increases the pressure at that orifice will also increase.... again simple physics.

Flush cleans the pressure valve that sticks causing higher pressures than the engine was designed for 

[Entwood]

You comments about the oil flush cleaning the pump, and the results being visible at the pump outlet are true ... as the pump is cleaned the flow will increase; the outlet is a fixed restriction and as such causes pressure, if the flow through a fixed orifice increases the pressure at that orifice will also increase.... again simple physics.

Flush cleans the pressure valve that sticks causing higher pressures than the engine was designed for 

and that relief valve is in the pressure line to the various journals, bearings , gears etc .. it is nowhere near the crank case covers !!!

The "engine" wasn't designed to take any pressure, the oilways and the items fed by them were....