Hi. Lets cut to the chase here... Check for 5 - 7 DC volts on the brush block wires with the unit running. No voltage = bad VR Voltage = possible bad brush block or... that you may need to flash the generator field. I know you asked for a service manual but I am telling you these simple steps will save lots of time money and grief.
If you disconnect ONE wire off the brush block you should be able to read resistance of the armature. If you can not read that resistance then the brush block is probably not contacting the slip ring. If you do read resistance across the brush block with one wire disconnected then it is time to try a field flashing.
The manual calls for applying 6 VDC to the brush block wires engine running to flash the generator field . Over my many years of working on generators I have found that you can use an electric drill plugged into the the power outlet and the output power switch ON. You then turn the drill as fast as you can by hand...(YOU MUST PULL THE DRILL TRIGGER at the same time.) It is a little work to do this but it works well. You must be careful though because once the field does flash the drill is going to run... i.e don't grip the drill chuck to tight or at least LET GO of the TRIGGER when it takes off! What ever you do avoid using a rag on the drill chuck while turning it.
Give all of the above a try first and if we really have to, I will dig out the manual and copy and paste text only :( pictures I will have to send you links for.
Thanks for choosing FixYa.
Kelly
Hi again. that is good news that you have the 5 - 7 V. I have to assume at this point the the brush block is worn. Do the resistance check across the brush with one wire removed. I would bet you don't read any. The end bell will come off without any problems. I will need a bit to digg for your info. 3:48 am here.. not to worry. Links to come with what you need to do.
Kelly
Hi again. After reading your last post I suddenly am wondering if your generator has a round generator head or square head? Just from what you said I get the impression yours is the square head. However your model number is for the round head.
If you have the round head unit... remove the end cover screws and it will come out of the way to the generator itself. The probe the brush block assy. wires. You should read 20 Ohms. (One wire MUST be disconnected. If you do not read 20 ohms remove the 2 brush block mounting screws in gently lift it straight out of the generator (No angeled movements) I am pressy sure your going to have one brush shorter than the other one. Possibly even some signs of melting of the brush block assy. (typical of a brush to short / worn out) Once the brush block is out... use a flashlight and look at the slip-rings through the brush block hole. The should be shiny and the same color. If one is shiny and the other one is a different color.. again typical of the brush not contacting the clip ring correctly.
I just spent the last 90 minutes trying to find my service manual and it has walked!
I think we can still get this task accomplished. It will just take some good communication.
Kelly
Mike,
Sad that is putting up a fight. Usually there are 2 screws (Item 51 Q of the parts manual) at 9 and 3 o'clock that you remove and off comes the metal cover. Are you speaking of the brush block having 2 nuts that won't come off? If they do have non captive nuts in there just jam a screw driver inbetween the brush block and the nut. CAREFUL as you get close to thenuts coming off... may I suggest you tear a small strip of masking tape and place it under the net so that when ti drops it does not end up in a place you where you can not get to it.
The part number for the brush module assy is:
0063230
(hopefully the picture link works) http://www.aaaa-generator.com/CP_63230.j...
With no resistance across the brushes the first suspect would be the brush block assy itself. You have the power to the brushes so that is half the battle. The rest is getting power to the rotor via the slip rings. If you ever do get the end cap off and the brush block out.. try reading across the two slip rings. You should read 20 Ohms. If you read 20 Ohms on the slip ring then the brush block is the problem. I am still digging for my missing maual. Not a happy camper at the moment as I just used it last week.
A note of cleaning the slip rings once the brush block is removed. Get a paint stir stick... and split it to the pint it will fit into the brush block hole. Then tape a small piece of cloth in the end (This still has to fit into the hole) Make sure the tape is on the stick. Over that tear off a peice of 120 grit or higher sand paper and tape that over the stick taping it tightly stretches at the attachment point. You can add another piece of tape lower down if need be. Your only going to use the very tip. (Presto - changeo! You just make a slip ring cleaning tool. Then stuff it in the hole and have someone turn the motor though ignition off. When both slip rings are shiny STOP. You don't have to do an over kill cleaning job. Take off the tape for the sand paper and use the cloth still on the stick to wipe off the sand paper grit.
I am hoping your not trying to take of the whole large metal housing end of the generator. If you had to take out any bolts so far you probably are not doing something correctly.
STATOR REMOVAL.
First thing you have to do is get the sator off of the rotor. The end bearing will put up a fight but gently tap top and bottom or the metal end cap until the large metal end cap comes off. I use a flat piece of metal on the mating surfaces then wood of possible. Just be patient and don't get in a hurry. It will come off of the bearing. Once you have that off the stator will carefully slide off the rotor. What you will have left is engine and rotor.
Rotor removal:
Now comes the fun part....
The first thing you do is find yourself a bolt that is treaded for about 3 to 4 inches that will thread into the end of the rotor where the long bolt was. (You will need teflon pipe tape too....!!) Then you tip the engine so that the rotor is vertical. You fill the hole all the way to the top with oil. Wrap the threads on that 3 - 4 inch threaded bolt you starting about 1/4 inche from the end and make several wraps.
Place some rags on the motor rear case. Start screwing in your bolt. Usually by the time you get to the half way point on the bolt your going to hear a BANG! The rotor just popped free from the engine and the oil you filled the hole with will have leaked onto the engine.
Like or not you just became a generator repair person.
Your rotor part number is:
0063940
It appears there is an alternate part number:
SBA7-190-001
I note that once internet source says you can not buy just the rotor. Check out the powermate.com website. They are the one that listed the alternate rotor part. This is their price list that lists the alternate PN
http://www.powermate.com/pdfs/2008/01/14...
Search for either number in the parts list 0063940 or SBA7-190-001 List is $210.00
I did a few internet searches for the SBA number and found prices from $157 - $217.00
Let me know if you need more help. I will stick with you on this. Actually it is fun on this end when someone is willing to dive into a task, communicates well and in the end the problem is solved.
Kelly
Nike I am just doing a follow up. How is the generator repar going? I get the feeling this is a weekend project but like to know where you stand at the moment on a remedy. I will keep watching for any responses.
Kelly
If you get this 2 times I spelled your name wrong and I corrected it. My apology to you.
Mike, I am just doing a follow up. How is the generator repar going? I get the feeling this is a weekend project but like to know where you stand at the moment on a remedy. I will keep watching for any responses.
Kelly
Hi Mike, It sounds like you found the problem and fixed it already. I will just tell you my own experience with short rotor wires.... I cheat and use a piece of solid house wiring 12 of 14 Ga (depending on size of rotor wires) and the solder it for some distance 1/2 inch + on the old wire after scraping of the shellac. I have also used a blue / clear epoxy on them (6 hour wait) to keep the bigger wire from being thrown into the stator. Hope your wife is fine. I would bet that it works like a champ once you get it back together. It was great working with you.
Kelly
Hi Mike.
There should not be anything that needs lubricated or painted with only 13 hours total time on the unit. Cosmetic touch up painting maybe if you dinged anything in the repair process. I am just glad that through a collective effort, it is up and running again.
The GFI outlet beng tripped was a good find on your part. I noted that in the memory banks here to check a 220V capable generator at the 220V outlet in the future. I usually do anyway but, that was good thinking and troubleshooting on your part. Once again it was great working with you.
I only ask that you posiibly comment via a testimonial comment about your experience here. Great work by you!
Take care.
Kelly
Mike, I never heard back from you so I am assuming there are other "Life things" keeping you busy. I hope all is well on your end.
I just got the notification that your generator problem is assumed to be solved which means you will see the FixYa Payment charge on your end.
Take care Mike and thanks for an interesting problem that you solved without a service manual. It makes my day here.
Kelly
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Hello Kelly,
I have measured 5.7 VDC coming off of the half moon AVR module screwed to the back of the generator (+ wire), and I assume that this is where the self excitation voltage comes from. From what you said that would be about right and a good voltage. I hesitated removing the end of the generator, I can only assume the rings and brushes are on the tail end? If and when I take it apart will springs and clips and puppy dog tails fly everywhere?
Do I need to take it apart to check the brush block voltage? Will I be able to recognize it, is this where the red wire (+) from the module I mentioned go to?
It does not look like the generator will run when I take the rear housing off to get to the brushes and rings, so any suggestions before I disassemble it?
Lots of questions, I hope they don't irratate you, just trying not to make a mistake!
Mike
Kelly,
I tried the drill, Wow times have changed it took me awhile to find one in my tool box, but no luck. I don't know which wires are the brush block wires to check continuity/resistance at. The only documentation I have is an owners manual I downloaded from Powermate.com and it doesn't show much (Brush Block or rings).
Any idea which wires I should check?
Mike
Kelly,
I tried the drill, Wow times have changed it took me awhile to find one in my tool box, but no luck. I don't know which wires are the brush block wires to check continuity/resistance at. The only documentation I have is an owners manual I downloaded from Powermate.com and it doesn't show much (Brush Block or rings).
Any idea which wires I should check?
Mike
OK I will start taking it apart to check the brushes. If I run into anything unusual I'll check back with you. It's raining here (Tropical Storm Hermine) so I may not get to it today, but I will try.
Kelly,
Attempted to take the end off of the generator and found two bolts inside the end piece that apparently have nuts on the ends so I can't remove them. Now I have the thing spread apart about 1/4" and can't get those two bolts lose or tight again..... All other bolts are removed.
Found brushes and they look OK unfortunately the rings have no resistance between them. I have to figure out a way to remove the end piece so the rotor can be removed for further testing/observation.
Any suggestions on how to get the silly thing apart?
Mike
Kelly,
My generator head is round and the brush holder looks OK, no melting or heat damage. The brushes are two different lenghts and the brushes look OK, I'm not sure how long they are suppose to be. My main concern is the fact that there are no ohms between the two rings, it shows an open circuit!!
I looked up the rotor cost and they don't sell just the rotor, you have to buy the complete gen head for 450 bucks!!
I may be getting ahead of myself though, I need advice on removing the stator and rotor assembly from the engine. I pulled the log bolt out from the center of the rotor, but nothing moves away from the engine. I now have all 4 bolts that hold the two halves together out along with the center bolt but it won't move. The two bolts that appear to have nuts on the backside do not look like they would stop the unit from coming off. Is the rotor compressed on the engine output shaft? Do I need a puller to pullthe two apart?
Mike
Kelly,
Sorry I disappeared for a few days, my wife went into the hopital on Tuesday and we just got back home on friday. Before I left though I found one problem on the rotor, the wire connecting the winding to the ring was broken right at the solder block. It would not stretch far enough to resolder so I had to reroute it a little and did get it resoldered. Once it was back on I measured about 60 ohms across the rings. I know you said 20 ohms but all looks OK with the rotor and brushes and stator, so I'm going to try to put it back together today and see if it will run OK.
The two bolts I spoke of were holding the rear metal housing to the stator housing and I had to remove it to resolder the wire on the rotor. If I can get the bolts back in and the nuts on the end the last task will be to reseat the stator housing in the housing on the motor end and find a plate to gently squeeze the rear housing back into place. Once that is done I can reassemble the unit and fire it up!
I will definetately let you know how it turns out and if I have a question or problem, I will ask.
Thanks for the help so far,
Mike
We have been sucessful in repairing the generator!! I put it back together, put some gas in it, fired it up and the LCD console came alive! It has 13 hours total time on it and 13 hours since last maintenance. I checked the 120 Vac outlets and didn't see any voltage then checked the 240 VAC outlet and saw 120 VAC between hot and nuetral the I was able to read 245 VAC on that outlet. I rechecked the 120 VAC outlets and noticed the GFCI was tripped on both so when I reset then it showed 120 VAC on both.
I the tried a small load test with a circular saw and it did run the saw showing 40% load and then down to 22%. I will try to load it more as it is suppose to be an 8.2KW generator.
Either way it appears we have fixed it!! Is there anything else I need to check, lube, thighten, loosen or paint?
Thank you for sticking with me and after you post a reply I will accept the resolution and I hope I can post very positive feedback!!
Thanks,
Mike
Kelly,
Yes my wife's recovery isn't going as planned, but they never do. I appreciate your help, I learned a lot and will definitlely leave a positive testimonial and gladly pay the fee. Thanks for sticking with me and enjoy the rest of your weekend.
Mike
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