"JohnM" wrote in message
...
Howard Eisenhauer wrote:
I'm looking at buying an Onan genset. It's a late 80's vintage 4 cyl
aircooled diesel unit, 120/240 single phase. Seems to be the same
model unit shown here-

http://cgi.ebay.com/ws/eBayISAPI.dll...ayphotohosting

As far as I can tell it has about 1500 hours on it since it's last
rebuild. I had the seller fire it up today & after warming up it was
blowing white smoke . The owner sez it was fine last time he ran it
back in June. It also seemed to take a while to settle down before it
ran evenly although there may have been some air in the fuel line.

Q.- Any ideas what the white smoke is all about? Is this likely to be
a tuneup item or something more serious?

Q.-What's a rebuild on one of these things cost?

Q.- Anything in particular I should be looking for/concerned about
with one of these units?

Q.- How much do you think its worth?

Thanks,

Howard.


As preciously mentioned the smoke is most likely from the fuel system.
Sitting since June is not that long for a diesel. Might be worth going back
and having another startup to see if the smoke went away.
Check the filters and see how new they are, check the water drain as well.
If they look ok, it might just mean that the thing has been maintained.
1500hrs is pushing it on a rebuild depending on what you plan to use it for.
What was rebuilt would be a good question. Normally the first thing to go
is the injectors and the pump. The injector pump tends to get pricey
rebuilding or new, depending on how common they are.

Keep an eye out for any ether cans lying around, meaning the machine is a
"dope addict". In my limited experience this usually means that there is
something wrong with the injector pump, again costly.

Would not think that air was in the lines as injector pumps are pretty picky
when they see air and you would see a cylinder misfire, or not even start
(or need the ether to get her running) if there was any type of air getting
in the lines.

Rebuilds get pricey on all diesels. I would think if the price is right and
you plan to use it for personal use, than jump on it. Clean the fuel out,
run some cleaner through the system, change the oil, check the rubber fuel
lines, you might see her purring fine. If she smokes a little well so be
it. Many a diesel smoke, and might outlast all of us. If after all that
you think it needs a rebuild and the smoke is still white, start with the
fuel pump (cheapest) and then the injectors and the injector pump. I say
this as there is no reason to rebuild the motor as it is, without redoing
the fuel system in a diesel, as it is normally the first to go.

No expert by any means, so take it for what it is worth. And God forbid, do
not let the run out of fuel.

--
Chris

If you can read this, thank a teacher. If it is in English, thank a
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