"Morgans" wrote in message
...

"Capt. Geoffrey Thorpe" The Sea Hawk at wow way d0t com wrote

Rather than a pre-oiler, what about grabbing the smog pump off that '78
Chevy you have up on blocks and putting it on your engine with the pump
outlet plumbed into the crankcase some distance away from the existing
breather? (Inlet goes to the clean air side of the air cleaner Note: IIRC
some air pumps have an inlet you can attach a hose to, some don't.)

Keeping the crankcase clean and dry would likely do more good than
pre-oiling...
That is the first time I have heard of an idea like that.

Of course it's the first time. I just thought of it today.

Where did you come up with that?

Thinking about how to do PCV (Positive Crankcase Ventilation) on an aircraft
engine.

Are there studies showing this to be of a measurable benefit?

I suspect that you could find a bunch of SAE papers from the '60s that get
into the impact of PCV and engine durability.

Example (quoting the abstract):
Some Effects of Experimental Vehicle Emission Control Systems on Engine
Deposits and Wear
SAE 710583
"Doubling the PCV valve idle air-flow rate greatly reduced engine rusting in
short-trip service, and reduced engine deposits and oil oxidation in mixed
city-suburban-expressway service"

I have had conversations with engineers that were around back then and they
were very sure that PCV systems made a big improvement in engine durability.
But I don't have any data handy. (I do control systems - not engine design
or lubrication)


I would think that keeping the interior clean and dry while running would
not do as much to reduce wear when the engine is started, as getting oil
onto the bearings and cam, before the engine is started.

Engines that run every day typically make it to TBO - engines that run 10
times a year don't. It's not wear from starting that kills engines before
their time, it's corrosion from all the krap in the oil.

My '97 Villager gets started from 2 to 8 times a day. To make a guess, it's
probably been started 15,000 times and the only sign of old age that it is
showing is a little lifter ticking following a cold start (probably because
I tend to not get around to changing the oil very often).

--
Geoff
The Sea Hawk at Wow Way d0t Com
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