"Peter Dohm" wrote in message
.. .

"Brian Whatcott" wrote in message
...
The Older Gentleman wrote:
Brian Whatcott wrote:

Oh yes, they tend to run them on natural gas. That's quite a favorable
factor, apparently.

I have to ask: why?



I don't have the definitive answer - but here's my guess.
Those pump engines tend to be carbureted, and atomizing the gas at high
throttle would be an issue. Burning dirty is not good for engines.
(One reason why fuel injected engines with ECUs in cars tend to go 100K
easily these days)
Natural gas gets you 100% atomization out of the box.

Brian W

That is most likely the reason. We used to run a standby generator on
propane, and never saw any unburned carbon buildup in the oil. So I would
expect natural gas to be at least as good.


Exactly the reason, as well as the reason late model fuel injected engines
live so much longer.

In the 60s and 70s it was common place to overhaul auto engines with 60k to
80k miles that would always require boring and oversized pistons. Today it's
common place to overhaul engines with 150k miles that require nothing more
than deglaze honing and new rings.

Unburned liquid fuels on the top of the piston rings are constantly
competing with oil from the bottom. This keeps the rings operating in a
diluted mix. Natural gas, propane and now even fuel injection, eliminates or
greatly reduces the dilution, and pistons and cylinders usually last 2 to 3
times longer, and more. The best example is a piston type air compressor.
They often seem to last forever even in continuous use.