Your last generator Maintenance Run

[ultrarunner]

Sounds like a winner... not much military surplus here since base closings.

On a separate question... is there a downside to "Brushless" generators?

 

[3930dave]

actually only about 330 hours. You can see by the ridges that it wasny riding properly on the slip rings. The old Nexus series generacs are known for this to happen. Not every one, but enough. Replacing brushes with an added spacer solves the issue. Newer ... after 2013.. dont have this issue.

Great data - thanks g.

Rgds, D.

 

[3930dave]

Thanks Dave! I figured if someone was looking at gensets they might appreciate an alternative to the retail options. I'm sure Uncle Sam spent a lot of my tax dollars to buy this one, but I was able to buy it 'again', including trailer, with my after tax dollars for $4k and it only had about 90 hours on it when I got it. Runs a 4 ton heat pump, electric dryer, and well pump simultaneously (along with all the other smaller electrical appliances in the house). Rated at 10kw but it's probably equal to a 18kw+ residential unit, and much more durable with it's 1800 rpm, 4 pole alternator, and emissions exempt. About 1/2 gal of diesel per hour at 50% load.

90 hours ! I suspect the trailer is similarly "under-built".....

I hope you wore a mask (old school non-covid type) when you bought that ! Heck of a deal for sure.....

I do appreciate how down-rated equipment like that is..... enough so you should write that one into your Will :laughing: , it's gonna be running for a long time.

Rgds, D.

 

[3930dave]

Sounds like a winner... not much military surplus here since base closings.

On a separate question... is there a downside to "Brushless" generators?

I haven't repaired enough of both to have what I'd call an Informed Opinion, but my :2cents:......... brushless may add complexity to the build.

Good quality manufacturer.... I don't see brushless as much of an issue - so long as things keep working, you've eliminated a maintenance requirement.

For low-end products, I might be more comfortable with brushes and a spare set tucked away.....

Rgds, D.

 

[ultrarunner]

I always liked the old Milwaukee products with quick change brushes... what a great time saving idea when on the job.

Replaced a lot of Model A Ford Generator and Horn Brushes over the years... but never a generator to date.

 

[3930dave]

I always liked the old Milwaukee products with quick change brushes... what a great time saving idea when on the job.

Replaced a lot of Model A Ford Generator and Horn Brushes over the years... but never a generator to date.

My corded Makita drill is like that, and same for a late 70's 1/2" Craftsman drill I bought new. Haven't put enough hours on either (or, just good brushes) to need to change them, but it's nice to have that external access....... grs would have appreciated thinking along those lines, that recent rainy day. I've changed the brush/regulator pack on a Bosch alternator on one of my older cars....easy peasey, as it is external access too.

Watching some of Jay's (Leno's Garage) recent lockdown vids with me, my wife commented on some of his cars from the 30's..... "Wow, were those hoods ever well designed, for engine access". She doesn't spin wrenches, but has some idea/appreciation of what I go through working on modern stuff......

Green Progress ?

Rgds, D.

 

[Chilliwack Murray]

The main reason brushes are used is cost and to a much lesser extent size on portable and RV units. Brushless requires an exciter stator, exciter rotor and typically 6 diodes and a surge suppressor on the rotor. This costs much more than slip rings and brushes that will almost always last the warranty period. It does take a little more space to hang all that off the back of the rotor, even more if you add a PMG to power AVR.

Unless there is a severe backfeed or reactive power condition a brushless system has an unlimited lifespan. I’ve seen many units with well over 60k hours with no repairs to the exciter system.

Brushes are a wear item as are the slip rings. The worst thing you can do is let them get dirty or worn down so they arc and burn the slip rings. Take care of your brushes and your brushes will take care of you.

 

[3Ts]

no joy on the t connection to the tanks. Just different kind of connectors at end.
Fine thread vs course thread, male vs female?
thoughts?
thanks Drew

If you're trying to put multiple tanks together, why not use POL (tank side) to NPT (manifold of standard black pipe "T"). The propane coming into my house from the regulator is black pipe and so is the pipe to my generator, so anything that is available in black pipe should be useable. The POL to NPT hoses are available at etrailer and run from 3' to 15' or so.

Attention Required! | Cloudflare

 

[LouNY]

no joy on the t connection to the tanks. Just different kind of connectors at end.
Fine thread vs course thread, male vs female?
thoughts?
thanks Drew

They should match up with the internal threads on the tanks,
they are left handed threads I believe.
At least I hope so.
Lou

 

[Chilliwack Murray]

Whatever you end up using, leak test it thoroughly with very soapy water or better yet commercial leak test fluid.

LP is not something to take any chances with.