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PU-286 B/G Start Up Procedure Questions


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  #1  
Old 12-03-2014, 07:00:13 PM
DMLinton DMLinton is offline
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Default PU-286 B/G Start Up Procedure Questions

Got my PU-286 B/G home last night. It has the Hercules ZXAER engine. I had initially planned to remove the engine for another project but, after casting eyes upon the genset, I would feel bad about parting it out without first trying to get it running in its originally intended capacity - generating electricity.

Visual examination indicates that the unit is probably complete with only minor deficiencies like the choke cable having been broken/disconnected, the duplex receptacle probably never having been connected in the first place and a main power wire disconnected.

I didn't get much response to my thread requesting manuals that I posted a few days ago. I do understand that these manuals are difficult to come by. I have message a couple of folks here that have indicated they have manuals but, so far, no joy.

Anyhow, poking around the 'Net, I found mention of the need to hold the starter button in until the engine reaches full operating speed, flashes the field and starts the generating process. I would like to confirm that I am using a proper starting procedure. The Auto/Manual/Crank toggle must, I believe, be in the up position (no juice to starter if in the down position). Upon engaging the starter, one must wait until the engine comes to full speed before releasing the starter button (else the engine just quits). Following this procedure, the engine can then be shut down using the Stop button. Can someone confirm that this is the proper procedure?

Note that if the above noted toggle is flipped to the down position while the engine is cranking and firing, it will usually pick up and run although the starter is then disabled. However, the Stop button then has no effect and the engine can be killed only by flipping the toggle to the up position.

Thanks in advance.
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Old 12-03-2014, 07:37:55 PM
Rich Mc Rich Mc is offline
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Default Re: PU-286 B/G Start Up Procedure Questions

I don't have the schematic for the 286B/G, here is the "G" schematic if this will help.
Attached Files
File Type: pdf pu 286 g.pdf (43.7 KB, 63 views)
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  #3  
Old 12-03-2014, 08:25:35 PM
DMLinton DMLinton is offline
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Default Re: PU-286 B/G Start Up Procedure Questions

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Originally Posted by Rich Mc View Post
I don't have the schematic for the 286B/G, here is the "G" schematic if this will help.
Thanks, Rich Mc. Can you tell me what the difference is between the 'G' and the 'B/G' is?

The schematic you provided compares very well with what I have except that the schematic specs a 6V battery while the guy I bought my PU-286 from says that it needs 24V. I have been starting it with a 12V battery but it is sluggish.

Also, there is mention of 75 AC Amps in the schematic while my understanding of the B/G is that the limit is 52 AC Amps. Is this a difference between the 'G' and the 'B/G'?

I think I read somewhere that the incorrect battery can influence whether or not the generator will come on line. Do you know if that is correct?
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Old 12-03-2014, 09:50:26 PM
Rich Mc Rich Mc is offline
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Default Re: PU-286 B/G Start Up Procedure Questions

I have no experience with either type units B/G or the G. Reading this schematic I see that there is no connection between the battery voltage and the AC section except that the battery is charged from the DC exciter on the main AC generator. If it is 6 0r 24 volts, 12 volts should not hurt it for short tests, maybe the starter has a data plate on it.

The AC section of the "G" is self contained and not controlled by the battery circuit but it could be possible the B/G may have a field flashing circuit sourced from the battery (applying a DC voltage to the main generator DC exciter field).

I see the ampere meter is rated 75 amps DC full scale and that would be a reasonable rating for a normal 52 amps running.

If the engine is running switch S1 {VR switch} in the off position (manual mode) should be the simplest way to trouble shoot the AC section.
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Old 12-03-2014, 10:14:20 PM
DMLinton DMLinton is offline
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Default Re: PU-286 B/G Start Up Procedure Questions

Thanks again, Rich Mc. Studying the schematics I have, including the ones provided by dougimes, I was wondering if switching voltage regulation to manual would be a good idea for AC side troubleshooting. Thanks for confirming that.

There are two terminals (about #8 slot head screws) on the right side (looking from the control panel end) of the generator bell that I suspect are associated with the DC exciter. I put a 9 volt battery across them - first with the engine off and then with the engine running - got a wee blue spark between battery lead and terminal at one point in case that is relevant. The 9 v battery also lost about 3 volts so something put a load on it. The AC output voltage went from 0.1 volts to 0.5 volts so it is looking to me like an exciter issue. I have no idea whether I had the polarity correct with the 9 volt battery.

There is around 100 kOhms line to line on the AC side so I think the stator is good. Didn't check each AC line to ground though - have to put that on my list for tomorrow.

I'm thinking now that the simple way to answer the starter voltage question is to check the DC generator output voltage. The DC generator (the battery charging one not the exciter one) seems to be working fine.
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  #6  
Old 12-03-2014, 10:45:01 PM
Rich Mc Rich Mc is offline
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Default Re: PU-286 B/G Start Up Procedure Questions

The G does not have a automotive engine generator. It also has a magneto. Do you have a distributor or magneto? These could be some of the changes from 286/G to 286B/G.
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Old 12-03-2014, 10:52:11 PM
DMLinton DMLinton is offline
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Default Re: PU-286 B/G Start Up Procedure Questions

Mine has a magneto. The battery charging DC generator is belt driven off of a pulley on the none drive end of the main generator.
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Old 12-08-2014, 11:37:05 AM
DMLinton DMLinton is offline
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Default Re: PU-286 B/G Start Up Procedure Questions

The PU-286 B/G generator has a somewhat unusual startup procedure. First, the engine and generator electrical circuits are distinct and separate systems. Hence, the suggestion, found elsewhere on the Internet, that the engine start up procedure provides for flashing of the generator exciter fields is NOT correct.

The are two engine startup modes - Auto and Manual.

Choking
  • choking is normally managed by the automatic choke.
  • the automatic choke can be over ridden by engaging the manual choke through operating the lever located on top of the air cleaner and adjusting with the choke control located in the control panel. I have not found it necessary to use the manual choke.
  • at temperatures below freezing, priming of the carburetor with fuel is recommended by operating the plunger located to the left of the carbureter. I do not know the recommended number of plunger strokes but 3 or 4 works on mine.
Auto Starting/Stopping
  • The Auto/Manual selector toggle on the control panel must be in the Auto position (up on mine).
  • Press and hold the Start button until the engine starts AND comes up to speed. If the Start button is released to early, the engine will shut down. Another member here, Mr. Mark Sedutto, reports that on his PU-286 B/G if the engine rolls but is not firing, releasing the Start button has no effect - the engine will continue to crank. He must flip the Auto/Manual toggle to Manual to stop the cranking process.
  • To shutdown, press and hold the Stop button until the engine comes to stand still.
Manual Starting/Stopping
  • The Auto/Manual selector toggle on the control panel must be in the Manual position (down on mine).
  • Choke same as for Auto starting.
  • Apply hand crank.
  • To shutdown, move Auto/Manual toggle to Auto.
Notes:
  1. The starter will not energize if the Auto/Manual toggle is in Manual position.
  2. If started in Auto, moving the Auto/Manual toggle to Manual will have no effect.
  3. If started in Auto, the engine can be shut down only by pressing and holding the Stop button.
  4. If started in Manual, pressing the Stop button will have no effect.
  5. If started in Manual, the engine can be shut down only by moving the Auto/Manual toggle to Auto.
  6. Upon starting, the engine will come up to full speed, i.e., 1800 RPM.
  7. The PU-286 B/G has a throttle over ride control located near the lower right corner of the control panel. It provides for idling the engine. It would normally only be engaged for engine tuning tasks. Mr. Mark Sedutto, who has provided me with an immense amount of advice, advises that he idles his engine down for a cool down period when shutting his unit down. I like that idea.

I should have noted in my previous post that the PU-286 B/G does, indeed, have a 24 volt starting system. I am using two 12 volt garden tractor batteries in series and find it works very well.
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Old 02-07-2015, 02:45:53 AM
YellowLister YellowLister is offline
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Default Re: PU-286 B/G Start Up Procedure Questions

I just stumbled across this post.. ive got myself a pu 286 nh according to the id tag on the gen end.

Im trying to figure out the right way to hook up 3 prong outlets to this.. ive posted in another thread the same issue.. looking at the diagram it still does not indicate if which is hot and the ground, (L1 and L2) my gen has two wires coming from the gen end.. going to a 50 amp breaker, out to the power outlet panel..

My pu 286 has a vacuum operated choke.. and will usually fire with half a pump from the primer, and yes having to hold the start button till the governor kicks in..

Mine is very quiet.. and I also have a strange coolant setup.. ive read these have a vent in the radiator. mine has a tube coming from the carb side of the radiator, going through the exhaust manifold, over the the water outlet on the mag side of the engine.. Not a lot of pics for me to compare to.. mine gets really hot, i need to get a temp gauge.. but ive only ran it about 10 min with no load..
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Old 06-05-2015, 07:15:16 PM
InterpreDemon InterpreDemon is offline
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Default Re: PU-286 B/G Start Up Procedure Questions

Have been running '286's for over twenty years. Glad to find and bump this thread. Have virtually all documentation and have digitized, so PM me if you need anything.

1. In auto mode, hold start until DC charging system comes up, which will kill the starter, AND THEN wait until the oil pressure gets above the "red zone" on your gauge, and the run relay will hold it up from there. No/low oil pressure and the counter (stop) winding in the relay will be energized by the oil pressure switch and the relay will not remain latched.

2. The cooling system runs at atmospheric pressure, there is a protected vent hole in the top of the radiator that must be kept open, and without a thermostat or water pump. It's what I call a "turbo thermosiphon" system in that the coolant actually boils around the cylinder jackets, absorbing huge amounts of heat in the phase transition, and the steam flow to the radiator sweeps along coolant as well. The steam in the mix condenses back and the cycle repeats. It is virtually constant-temperature and operates with perfect reliability over an extremely wide load and ambient temperature range. The tube that runs from the block through the exhaust manifold coupling and on to the radiator allows a small flow of coolant to go through that coupling and boil off, which keeps a "close on rise" thermo-switch in there cool enough to remain open, however if the coolant level drops too low the flow stops, the switch heats up and closes and it drops the run relay the same way the oil pressure switch does (they are in parallel).

3. Run only as little anti-freeze as necessary to protect in your climate since more antifreeze raises the boiling temperature and thus the temperature of operation. Here in New England I run 20%, which is only good to about +15, but my garage is heated to 40 deg AND my generator starts automatically at 32 deg and runs until it is 40 even if the garage heat fails. To mitigate the higher operating temperature even with only 20% glycol I also run mid-grade gas in the Winter and premium in the Summer to reduce the risk of knock under full load. In a warmer climate without freeze risk I would just run plain water and regular gas.

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Old 06-05-2015, 10:42:21 PM
InterpreDemon InterpreDemon is offline
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Default Re: PU-286 B/G Start Up Procedure Questions

Quote:
Originally Posted by yellowlister View Post
Im trying to figure out the right way to hook up 3 prong outlets to this.. ive posted in another thread the same issue.. looking at the diagram it still does not indicate if which is hot and the ground, (L1 and L2) my gen has two wires coming from the gen end.. going to a 50 amp breaker, out to the power outlet panel..
This generator does not have either 120v leg bonded to the generator equipment ground (frame/chassis), and depending upon how you intend to use it, as a separately derived power system, for example to use at camp or as the worlds heaviest portable, or wired into your home as a standby unit, will determine how you configure the output. Many of these units have been altered over the years, both on the AC side as well as the DC side, the latter due to few having any idea as to the intended operation of the original wiring and/or not being able to run it as origonal due to missing/bad parts made of unobtanium. So, "your output may vary", though the original was in the form of a duplex, two prong outlet and of course the large terminals below as well as the unobtanium, grounded body two-prong Cannon plug connector.

If you were to use it for portable operation AND the duplex receptacle has been upgraded with the three-prong, grounded model (many have been so upgraded over the years because modern polarized plugs will not fit in the old two-prong even with the ground pin snapped off), the simplest thing to do without modifying the generator itself would be to make a shorting plug you can plug into one receptacle and your extension/break-out cord in the other. First, switch off the 50a breaker, then make sure you have continuity between the ground socket(s) and the generator frame... most receptacles will make this ground even with no wire connected to the ground lug, but you should make sure you have a green wire bonding that ground to the box anyway... and since almost nothing works in an old two-prong receptacle anymore you might as well upgrade if it was not done by a prior owner.

Once that's out of the way you have two options, 1) a shorting plug if stand-alone operation is only temporary and 2) a jumper on the lower output terminal strip if more permanent, for example at the hunting cabin. The shorting plug is easy... just pick up a three-prong plug and install a short internal jumper between the ground pin and the wider of the two spade pins, which is "neutral" (left if you are looking at a receptacle), and screw the back cover back on... that's it. When you plug that baby into the duplex outlet you will now be making one of the 120v legs neutral and bonding it to the frame ground of the generator, the other leg being "hot". This will be fine if you are only going to use the other receptacle in the duplex to power something, however if you are going to use the lower terminal lugs for power, you need a better bond, SO... making sure the main breaker is "off", use your ohmmeter or continuity checker to determine WHICH of the two L1/L2 terminal posts is ACTUALLY mated to the neutral (left/wide) side of the duplex receptacle... they often get swapped around over the years, so you must check, then run a heavy jumper from that terminal post to the bronze frame grounding post right below. If the generator is at your cabin, that frame post is also where you will be tying in your ground electrodes and building ground system, depending upon the size and complexity of your distribution system. That separately derived type system, as well as proper wiring into your home as an automatic or manual standby system are long topics for another thread/post, but the 286 does indeed make for a terrific standby system, mine with hundreds of hours through hurricanes and nor'easters the past couple decades.

Another thing regarding portable operation. Keep in mind the protection as-is is at 50 amps, which is too much for any extension cord distribution system, in fact it's too much for the duplex receptacle and wires powering it from the control panel, so a good idea would be to wire a small 4 or 8-circuit breaker panel to the terminal outputs, or use a computer power strip with a breaker from the duplex, etc.
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Old 06-09-2015, 05:01:55 PM
DMLinton DMLinton is offline
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Default Re: PU-286 B/G Start Up Procedure Questions

Thanks for all the additonal, and very useful, information, InterpreDemon.
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