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Detroit 6-71

I bought this generator in auction for $300 plus BP:

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It is an old 250 kVa emergency generator with 886 hours. Located inside a GE facility in Chicago.

It has an engine that looks like Detroit 6-71 with a turbo.

I have always been kind of a sucker for those detroits (first made in

1938). Once bought, tested and resold a 3-53 and loved it. Could not pass up a chance to buy the whole generator for $300.

Anyway, in my own mind, I would make more money if I separate this generator and sell the Detroit separate as a running low hours engine, and sell the generating end to be used with some other engine.

My own reasoning is that very few people would want this as a generator, because it is really noisy and not fuel efficient and leaks oil (they all do).

A 250 kVa generator is too big for a typical house or farm and would only be usable for special needs, and usually companies with big money would rather buy a $100,000 new generator that is EPA compliant, than some old generator for $10,000.

Whereas, I am thinking, there is a million uses for a good condition

6-71 diesel engine, like old tractors, landing crafts, or who knows what.

Makes sense? Separate or not?

i
Reply to
Ignoramus32337
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No shit, Sherlock. Congrats, and YOU SUCK!

What kind of engine would it take to provide 20kW from that genset? If it's small, perhaps the separation would be a good idea.

Reply to
Larry Jaques

Ignoramus32337 fired this volley in news: snipped-for-privacy@giganews.com:

I've worked on a LOT of 6V51s and 12V71s in 'Nam.

They're real workhorse engines. Even today, some modern custom-built tour busses and other vehicles of their ilk carry the same motors.

YOu may find the blower bad (at least its bearings), but you'll almost certainly find a home for the motor. Probably much more likely to than if sold as part of the genset.

One question, though... 'turbocharger' or 'supercharger'? Most of the older ones came stock with top-mounted mechanically-driven blowers (superchargers). Being a 2-stroke, pressure-aspirated motor, I'm not sure it would even start without at least a supercharger, even if it had a turbo, as well.

Lloyd

Lloyd

Reply to
Lloyd E. Sponenburgh

Right. They are awesome if you do not mind the noise, some lesser fuel efficiency, but like simplicity and reliability.

OK, so we agree.

Lloyd, it has a green roots blower on the side, you can see it. It ALSO has a turbo on top (you can also see it). You can press the magnification icons near the photo to magnify it.

i
Reply to
Ignoramus32337

Thanks... Kind of excited... Picking up wednesday...

You can use any kind of engine, but it probably needs the correct connector plate for the generator end, I will see once I separate them.

i
Reply to
Ignoramus32337

Ignoramus32337 fired this volley in news: snipped-for-privacy@giganews.com:

Ok... I see it now. It just looked like "background" until I magnified the picture.

Yes, with both a blower and the turbo, it should be a good motor, and relatively efficient -- but still check out those bearings in the turbo (unless you find a customer who already knows and doesn't care).

We ran them in boats with only the blowers, and they were still dynamite motors with lots of long-term reliability.

No wonder custom-builders still seek them out and refurbish them to "like new" condition.

Lloyd

Reply to
Lloyd E. Sponenburgh

"I gots t'know": what is Lot 52 "NOROPRESS; M# HSBL; KRAFT MAX 150 KV; HUB MAX 120MM; DRUCK MAX 150 BAR"

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Reply to
Bob Engelhardt

Gunner Asch fired this volley in news: snipped-for-privacy@4ax.com:

Minimum 200 hp. Something like say.. a Detroit 6-71

??? I can provide a good, solid 8KW from an 18HP engine.

So, you're saying that 2.5x that would take TWELVE TIMES the HP?

Somebody's numbers are wrong -- maybe mine.

Ig said it was a 250KVA (250KW). You're saying 20. ????

Lloyd

Reply to
Lloyd E. Sponenburgh

I recognize the words at least. Kraft = strength, power or force (but voltage is Spannung), Hub = stroke, Druck = pressure, 1 Bar ~= 1 atmosphere.

Does the Master heat gun go with it?

Perhaps that combination wrings confessions from the souls of the dead?

-jsw

Reply to
Jim Wilkins

The picture sucks. That may have something to do with the fact that I got it for $300 plus BP.

I do not know how I can check those bearings, as they are inside the turbo.

They are very lovely and very MANLY motors with a bad ass sound. They have that general BAD ASS attitude and that's why people love them. Plus a lot of power for weight and generally reliable if not pushed too hard.

I think that at this point in time, the market for them is entirely driven by nostalgia, not by money making or convenience considerations. Whoever specifies one for their boat do it for nostalgic reasons.

I love those motors too.

Here's the 3-53 that I sold four years ago (or so). All pictures were taken with the motor running.

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I bought that one for $200, forgot what I sold it for.

i
Reply to
Ignoramus32337

OK, I will drop it in my yard and will try to sell as-assembled.

OK, sure, I can sell it "complete or just engine" same price.

The gen end has some scrap value too as it is likely made of copper.

i
Reply to
Ignoramus32337

It is 250 kVa

Reply to
Ignoramus32337

It is a "NOVOPRESS", a modular pressing and cutting system, I think of German origin. It went for $120.

I got lot 58, which is a copper bar cutter novopress. "druck" means pressure. Lot 58 went for $100 and included several Dayton vises and a Reelcraft compressed air hose reel.

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i
Reply to
Ignoramus32337

Ignoramus32337 fired this volley in news: snipped-for-privacy@giganews.com:

There's nothing you can do to hurt them except not keep them full of clean oil and filters, and never, ever, ever over-tach them. Other than that, they're bullet-proof. You _cannot_ 'overtorque' them unless you LUG them -- so long as they maintain their set speed, they are working in their 'reliable' realm.

Custom coach builders are still using them as if new engines! There's no 'nostalgia factor' in picking a solid, bullet-proof motor that will go

300K-500K miles!

Lloyd

Reply to
Lloyd E. Sponenburgh

I see a 6-71, with marine transmission, listed on E-Bay and

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has a 4-53 listed for $11,200 outright sale and $7,200 with core. The same company has "overhaul kits" for the 71 series for from $1,000 - $3,000.

There is apparently a demand for the engines.

Reply to
John B.

Would this pass emissions tests?

Think about this.

Let's say that you install this engine into a bus or medium truck. You would get, say, 8 MPG.

With a newer, more efficient, engine you would get 9 MPG.

This means that if you drive 60 miles in one hour, you would pay for about one extra gallon of fuel. Say $3 per hour.

If you drive 10 hours per day, you would spend $30 extra per day on fuel.

If you drive 250 days per year, you would spend $7,500 extra on fuel.

Over the expected lifetime of 500,000 miles, you would burn 56,944 more gallons of fuel with the Detroit as opposed to a new engine, which is equivalent to, say, $170,000 dollars in additional costs.

i
Reply to
Ignoramus32337

20 KW is about 27 HP. allow say 50% for incidentals and you could probably build a 20 KW gen set that would last forever with a 40 HP engine.
Reply to
John B.

Gunner Asch fired this volley in news: snipped-for-privacy@4ax.com:

Pretty close, if you're supplying a combination of resistive and non- syncronized inductive loads. C'mon, Gunner. I know 'Watts' are only volts times amps in a DC environment, but we still use the term to describe VA in an AC environment (approximately).

Lloyd

Reply to
Lloyd E. Sponenburgh

Gunner Asch fired this volley in news: snipped-for-privacy@4ax.com:

Yeeessss... you didn't read another word of what I wrote, except "pretty close".

Power factor has to do with voltage vs. current phase relationships.

With purely resistive loads, its 1.000. With most 'common' inductive loads (motors, not loaded exactly optimally), it can be as bad as 0.6. BUT... it depends entirely on the load's individual characteristics. And two inductive loads of about the same power factor, and out of rotational phase enough to present each's peak current at the OTHER's peak voltage end up 'looking like' a 1.0 power factor. Given enough of them, randomly chosen and non-syncronized, they collectively approach a power factor of

  2. Since "residential loads" (as you expressed in your first comment of how many homes could be supplied by this) are a mixture of many, many purely resistive loads and a few totally non-syncronized inductive loads... You'd realize _about_ 250KW worth of energy from a 250KVA genset.

LLoyd

Reply to
Lloyd E. Sponenburgh

But Gunner, let me add just one more thing you apparently ignored.

Say, for grins, that the power factor WAS 0.8 (about normal for ONE motor, inadequately loaded).

Then the 250KVA generator would be providing a 'useful' supply of 200KW.

That's still a HEAP more than 20 !!

Lloyd

Reply to
Lloyd E. Sponenburgh

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