Foretravel Owners' Forum

I'm up at texhub's place in uvalde and we are trying to pull my 10 KW power tech generator with Isuzu engine to change out the end bearing and the motor mounts along with a new voltage regulator and breaker. Having issues with getting the unit out of the coach due to the exhaust pipe. The back side of the exhaust manifold has a 90° elbow that connects to the flexible exhaust that's covered in a heat shield cloth. While trying to remove one of the four exhaust bolts one of the studs broke. Everything is very Rusty back there. PB blaster was used but I didn't let it sit overnight cuz I'm in a hurry. What I'm trying to find out is how the flexible exhaust is connected to the 90°. I can't really tell for sure cuz it looks to me like it's just shoved into the 90° elbow but I can't imagine how it would have been secured that way. I'm thinking of cutting the pipe below the 90° elbow and trying to figure out how to join the two after it's out. If I can get the other nuts out once everything is out and I can work on it then I would try to do that and just replace those parts, but then I would have to get that stud drilled out and retapped and I'm not sure that I have time for that nor do I have the tools for it although there may be somebody local that could do it but then I would probably have to take the exhaust manifold off and that opens up another whole can of worms that I don't want to deal with.

So the question is how is the flexible exhaust pipe connected to the 90° is there another pipe there that I'm not seeing maybe the exhaust pipe goes over it?
I need somebody who has done this job to tell me how they did it. I just spoke to David also known as John 44 and asked him about how his went but he doesn't remember other than thinking that he just was able to get the nuts off the studs.
Thanks
Bob

Pretty sure that pipe is welded to the nipple that is screwed into the elbow. That flex pipe is also some type of stainless.

Thanks red tractor. So you think that the flexible pipe is welded to the nipple elbow?

I was working on a 8000 kw with the Isuzu engine but it looked like yours.

Sorry for your troubles Bob, my exhaust was wrapped so I can't answer your question on how the flex connects to the 90 however I would suggest carefully working on the other 3 nuts and get the Genny out and evaluate from there.

Thanks. Found a wire brush and put it to both the nuts and the exhaust hose. I think it's welded, so will try the nuts after the PB blaster does it's work overnight.

All I did was pulled the generator out on the slide to change the bearing. The voltage regulator can be changed the same way
and I don't see why the motor mounts can be done with just pulling the generator out on the slides. I hope this helps.

On my '99 with the same Isuzu generator it will only pull out enough to change the oil. Unless you disconnect the 2 fuel hoses in front, mark them so you'll know when you hook back up.  With the hoses disconnected the generator will slide out further which might give you enough room to change the bearings.

On my 99 when I went to change the bearing I realized that my 12kw generator is different than the lower kw models and it has an external exciter coil on the end.  Removal looked a bit daunting and getting further past that looked impossible (there was just a bolt hole thread but no bolt in the end).  If anyone has the 12kw and does this, please make a video, take pictures, etc.. Anything to help.  I simply reassembled and ignored the problem for the last few years but I have the new end bearing ready to go in and I really should go after it again.  I was actually with Paul Yasbeck when we attempted it and even he was a bit confused.  I'd presume he's seen just about everything.

My 10K has the same exciter coil you describe. Look at the pictures and let me know if the coil looks like what you have.


How not to change voltage regulator in genset (https://www.foreforums.com/index.php?topic=32784.msg294847#msg294847)

Just talked to Bob,it's pulled out enough to change bearing,he will deal with the exhaust bolts later,hoping exhaust won't leak
with the one broken bolt.

Okay so I pulled the end of the generator off and yeah I have the kind with the Exciter at the end. Getting to the bearing is going to be a little more challenging than I thought. At this point I'm not quite sure whether to proceed or not.

I worked on a power tech generator last year and replaced that flex pipe. Called power tech and sent a new flex pipe. Power tech welds a pipe threaded nipple on each end of the flex. I just put a new elbow on that 4 bolt flange and threaded the flex pipe into the new elbow.

Bad things happen when the bearing fails - it can take out the entire generator end $$$

Kubota electrical generation failure (https://www.foreforums.com/index.php?topic=10686.25)

(sorry that the YouTube link doesn't work anymore, but it showed that the entire thing was wobbling and parts had "destructively contacted each other")

If you have parts and you're close to the changeout interval, I would bite the bullet and do it.

You just need to undo the wires from the exciter in the box. Mark the them so they go back the way the way they are pull them
out. Then remove the 4 allen head cap screws and pull off the exciter. The bearing is now easy to remove.

Here is a link to a thread from awhile ago that has a reply as to how to remove the exciter.
tech bearing replacement (https://www.foreforums.com/index.php?topic=39397.0)

Mike

I did remove all eight of the Allen bolts the four smaller ones in the middle and the four outer ones that are larger using the torx tip socket. Then I tried to remove or budge and it wouldn't budge. I didn't remove the two wires at that point because I wasn't sure I was going to proceed any further I just wanted to see if I could get it loose and I could not without maybe hitting it with a hammer or a mallet to loosen it up a little bit and I didn't want to do that. There was a lot of debris inside the generator and including flaking paint dirt and other tidbits. Two previous owners ago, Paul Smith used to take my coach down to Cancun in parts South regularly, so I think maybe there is some corrosion there that's holding everything together. That's when I decided at that point that it was no bueno!
I really understand about changing the end bearing so maybe I will go back out and take those four outer bolts out again and try it with the rubber mallet if I could find it. Also on the end there is a little bolt do I need to take that out? It's in the middle. Or is that part of the spindle shaft and will be exposed when I take the Exciter part off? I've already decided that I've had it with this generator and if I blow it up I'm going to remove it and use that space for an additional 600 amps of lithium batteries and increase my solar capacity from 1400 watts to 2000. That would allow me to run my air conditioners off of lithium during the day with solar and it's rare that I would use the generator all night anyway. Even though my coaches in all electric coach my 600 amp so lithium gets me several days with solar even more so doubling that capacity Plus going with a victron DC to DC charger 100 amp would give me both air conditioners running down the road off of solar and off of upgraded alternator.
Anyway I don't know if that's going to happen but at this point I'm a little bit frustrated with the whole thing.
Just a little picture to show the difference between the old breaker that power tech put in and the new one good. They're both 50 amps 240 volts but they're made by different companies. The old one was made by Eaton heinemann and it's much larger. The new one is made by Carling. I forget exactly how much right now that power tech charge me but it was well north of $100 I could have bought the same one on eBay brand new for $38. It may have been north of $200 for the power tech one. Just a little rant to make you smile.

Thanks. I read that I remember thinking that if I had to re-exite the generator head, how would I know if it was a male or female generator?
I will try it again....

Okay and looking at the picture again of the generator Exciter there are inter bolts that are torques and outer bolts which ones do I remove to get to the bearing? Now bear in mind LOL that I removed all eight of them and nothing budged...
So reference picture and do I take the bigger torques bolts out on the outer frame or the inner ones? Thanks

Remove the nuts on the Q & R leads and move them out of the way. Make sure you mark which is which as if you put them back wrong it will let the smoke out when started. Then remove the center bolt and washer that you can see behind them. That should let the rotor portion of the exciter come off by pulling on it. Now if it is stuck on the shaft you will have to encourage it to come off.

Mike

Thanks Mike but how do I get to the bearing once those wires are off?

Never mind I've read the post again and I think I got it. Thanks for the advice I'll give it a try hopefully I will not let any smoke out!

Are you talking about the bolts on the wires plus the 3 that hold the exciter on?

I removed the wires and mark them I removed the center bolt and marked it. I removed the three nuts that were on the inner part. But there's six wires going to that do I remove those too? What is supposed to come off is it just a very center which is made out of a composite type material or the windings that are around it as well? I don't see how I would be able to get to the bearing by just taking the middle out.
I got a call into Jeff for tech support but don't know if I'll get a call back today or not mean while my generator sitting out there.

I forgot all about the center wires. The 6 wires don't need to be taken off it all comes together. I should half taken more pictures
when I did mine it would have help.

Old guy can you be more specific in how you got the Exciter and rectifier off? I really would appreciate it did you have to apply any pressure to it? If so how did you do that?
Still waiting on a call back from power tech I don't expect to get one today unfortunately the way things are going I might have to call him back tomorrow meanwhile the end of the generator is open to everybody that can see it I should at least put a pair of panties on it.
Thanks
Bob

If I was there I would know exactly what to do. I think the exciter should just pull off or is it part of the rear frame. I know that
the rear frame comes off I just can't remember if the exciter comes off first. You have undone the three bolts is it loose now.

The exciter has to come off first.

All right bearing is out it's a long story and I will fill everyone in on the correct procedure to remove it later. Now how do I put the bearing the new one on? Do I use like a deep socket and Hammer it in I can't use a piece of wood because it wouldn't go on evenly how did you put that bearing in?

I heat them up and slide it on. It doesn't take a lot of heat but you need to be careful and not damage the seal. I have a lot
of experience changing bearing so I don't know if I should recommend that way. I used to use a brass drift and hammer
but I prefer heating them.

Not good to heat a sealed with neoprene bearing. It didn't take much to put the bearing on mine. Clean the shaft with emery or steel wool until the varnish is off. I used a piece of pipe to drive mine on.

Do what Craneman recommends as in using heat can be tricky. 

You could also wrap the bearing shaft in dry ice for awhile, would help.

Bob,use a pipe or a socket to pound it on but only on the inner part not on the outer ring.

I like both the idea of super cooling the shaft and using a driver on the inner race.

The safest way is to use a pipe that fits over the shaft and fits squarely on the inner race.  The other way, is to use an oven set to 200F for an hour.  But that requires steady hands and one smooth movement until the bearing is seated.  In an industrial setting you would have access to an induction heater to heat the inner race.

Someone with experience could install that bearing with a punch and hammer but that is not for the unskilled unless you're installing someone else's bearings.

Bearing mounting|How-to: Handling & Aftercare:Bearing Handling|Products &... (https://www.ntnglobal.com/en/products/instruction/mounting/index.html)

Can you say BRASS DRIFT! And tap, tap, tap in criss-cross all around the circle.

So lots of learning as well as mistakes made in this job. I still have to wire the breaker box tomorrow but as for now the generator has four new motor mounts, a new 50 amp breaker, a new end bearing which was a mother of a job. Unfortunately people that made their prior threads about this job forgot to mention the humongous snap ring that holds that part in. Luckily I found it cuz I couldn't figure out why the thing wasn't separating the snap ring was hidden by some grease but when I sprayed some brake cleaner on it all the sudden I was like hey what is that? Then I made the mistake of using a puller that damaged the initial threads on the shaft. You really need two different pullers to do this job. The first one I got from harbor freight based on John morales's recommendation. And while that is a good puller for pulling the rectifier and Exciter off it does nothing for the actual bearing. To get the bearing off you need to use something that has claws that wraps around the back of the bearing. Luckily Mark and I went to O'Reilly's and they had a loaner bearing puller. And it worked great except for a damage the threads in the shaft. And then I damaged the bolt trying to get it into the threads.
So back to O'Reilly's for tap and die kit. Did I cleaned up the threads on the boat just fine but then I could not get the tap to cut new threads inside that stainless steel shaft. I tried and tried. Finally I was almost ready to give up I called John 44 who's going to hook me up with somebody local that might be able to help, as well as reaching out to old tool maker to see if he had any ideas but I couldn't get a hold of him. I finally an act of desperation I put the tap into my Bosch half inch impact driver and ran it at high speed with some oil and it finally started cutting. Took quite some time to get that to do it. So now I fixed that boo boo.
I got everything put back together again there was about to put the end of the generator on and look down and there was a snap ring sitting on the table. I forgot it so I had to pull everything off again but of course not the bearing this time put the snap ring in and back again everything. The motor mounts weren't too much fun either because the back mounts have a bolt that is very difficult to access from the bottom you can't get it from the back side of it only from underneath and my pan was full of grease and oil and gunk. 20 years worth. Getting some of the holes to line up became a challenge to as well but out came the trustee 48 inch pipe that I bought in Arizona to do the shocks with and that was able to lift the generator enough to get the old mounts out and the new ones in. I wish I had put new hardware in for the motor mounts but I don't have access to good stainless steel hardware here in uvalde. And I didn't feel like riding two hours to a Lowe's in San Antonio. So now what's left is to rewire the breaker box and I'm pretty nervous about that. I took pictures of course and labeled things as best as I could but I missed some of the wiring when I took a picture of the breaker and I'm a little nervous about wiring it back up again. Of course I did call power tech 2 days ago tech support I'm still waiting on a call back from them I got a feeling Jeff will call me next year. Once I get the wiring done will run up the generator burp the coolant system and probably have to burp the fuel as well get any air out. And then we'll see. There's much bigger job than I thought it would be but if it works I'll be happy and if it doesn't I don't think I'll replace the generator with another one.
Oh and the way I got the generator bearing in was just to do as craneman suggested and cleaned it with some steel wool, then I cut a four inch section off my galvanized pipe that I use for a breaker bar extension, and hammered away with two and a half pound Sledge hammer. I tried the large socket but it was hitting the inside of the shaft. The old bearing was still good but the new bearing is smoother.

Attached are some photos. 1. picture of 2 of the old mounts. The top 1, the center was rusted to mount bolt. RemovaI showed the center was detached. I think bolts in center should have anti seize applied on install. Appears that this mount was bad. Allowing passenger front of generator to lift up/down. With no external sign of bad internal status.
Get 8 new stainless bolts for the bottom of mounts. 2 per mount.
The pipe we cut to use for bearing install is 11/4 galvanized this allows for only inner race contact. Could just use any steel.
Other pictures are just showing restore.
Please note. This was a quick, no shade repair, in Texas spring bugs/heat. No pressure washer, etc. Plans had to change as job took longer and parts were such an issue. Bob did build new mount for the new cb. Its stainless light cover that you now see on passenger side of control box.
Generator is
Powertec 3 cyl diesel, with 10 k head, no bearings.

Sorry I couldn't remember a lot of what I did. I should have taken more pictures like you have. The trick when using a puller against
a threaded shaft is to put a nut between the puller and the shaft and that will protect the threads in the shaft. If the new bearing
felt smoother than the old one, I would say the old bearing was shot.

Old bearing you can feel the rollers rolling. Doesn't have abnormal play outside of desired movement. Just can feel crunch. Like walking on snap, crackle, pop! New bearing, smooth, no feeling, no CSP. 

Yeah old tool maker pointed that out to me too after. Unfortunately 35 years in the medical field didn't prepare me for that kind of stuff LOL. But I didn't think that it would go into the threaded area but it did. Hopefully someone will learn from my mistakes which is the point of the thread now anyway. Originally it was a cry for help. I get to wire the box today and fire everything up fingers crossed.

Sorry about that Bob.  I was out leading the glamorous life of the full-timer, perusing the aisles of Food World, WalMart, and Lowes.  Congratulations on coming out the other side.  That's a daunting job to undertake and the best way to learn.  And boy, did you learn! 

Bob, did your generator work? A the bearing and Voltage regulator where replaced on mine it had to be excited.

What are the steps to excite the generator head?
10K model

Mine didn't need exciting started up and had power. I think brush type need exciting.

So far wiring the box has been smooth. Notes taken. Photos also. Wires checked for any damage, signs of corrosion. All wires show age.  Heavy rain delay. By sunset, should be able to test.

Mine  is brushless. I don't remember the procedure to excite it.

Well as the grateful Dead said... What a long strange trip its been. Yesterday evening Mark and I spent several hours trying to reinstall the EPO power watch dog. Finally I took it apart and saw that what they use is one of those six-way or four-way crimping tools that makes a square crimp out of a copper tube. Not having that tool I improvized. I have a ancor crimper that looks like it might be for category 4 or 5 connections. We experimented and found that it made a decent crimp for what we wanted to do. At least 80% of it. Mark finished it with some vice grips and we were able to fit it in the round holes that are in the watchdog and they wouldn't pull out. Both stranded, fine and course, 6 gauge wire just would not stay in place. With this method All is now well with no stray wires. So this morning found us firing up to genny, and it fired right off. First black smoke then white smoke then no smoke. And it ran really nice for about 20 minutes when all the fuel in the fuel filter ran out. And then it died. So we figured it needed to be bled. After trying to for 20 minutes we realize that the fuel lines were reversed so we corrected that, we bled the fuel system starting at the fuel filter and moving up to the fuel rail system that feeds the injector ports. Now it started and ran like a champ. We let it run for 20 minutes until the thermostat opened up and then we bled the coolant system. It needed about 2 quarts maybe of coolant to top it off and then we continue to run it for a little while. All the while it was running fine. Of course the generator breaker was off cuz I did not want it making power yet. Then I went inside while we flipped the breaker on the generator box., And I flipped my manual transfer switch to generator. Nothing. The power watch dog was dead except for a small red light that came on only once saying that the park power neutral was bad. Now I know that wasn't the case because my multimeter showed that I had 122 volts between neutral and line one and line two separately both at the transfer switch and at the input side of the EPO power watch dog. So as I suspected that thing had given up to ghost at the RV Park in Corpus Christi. I had put a call into tech support from them and never got a call back, not a surprise. So then it was brainstorming to try to figure out what to do next. Mark graciously gave me a male 50 amp plug and several feet of 6 gauge fine stranded wire from a shore power connection. I removed my old wire that had those nice square crimps that I wanted to save and put the new wire into the main breaker box. I then plugged the male and into another EPO power watch dog, the plug-in model that I had and plug that into the 50 amp female plug that I had already installed under the bed. Fired the generator back up flipped the breakers on turn the transfer switch to generator and all was good. Power watchdog came on no fault codes. So I set my victron multimeter at 10 amps and started adding some 120 volt loads to it. First big load of course was the battery charger in the victron multiplus to charge my battery bank that was down to about 60%. I think that's 120 amp charger. Increasing the amount of amps that victron would allow, I now turned on the rear air conditioner which has no soft start, and it ran fine. Then I turned on the front air conditioner which does have a soft start, and again everything was running fine I turned up finally to 50 amps and the generator was under a good size load at that point with no hiccups. Starting was no issue the vibration that I used to have was pretty much gone. And to my ears the generator sounded quieter than normal. Not by much but some. I let it run for several hours and not a hiccup everything ran like it should. The only thing I didn't put on was the electrical heater on the aqua hot. I felt that I probably would have overloaded the circuit at that point with everything else running and I didn't need hot water anyway.

So lessons learned.
Always always take lots of pictures before you start, and as you go along. Don't work when you're tired or frustrated or hungry or thirsty. Take a break. Mark everything. Mark had a big tray of multicolored zip ties and that helped a lot. When using a bolt puller leave the bolt 🔩 in the threads so that doesn't damage them.
For this type of a job you need two different pullers. The one I got from harbor freight for 15$ was good for pulling the Exciter off, but it would not pull the bearing off for that you need one that has grips on it. You also need a decent snap ring tool. The one that I got from harbor freight is fine for small snap rings but will not do the job for the big one. I finally got it off with a small ice pick and a small screwdriver. Putting it back on would have been a challenge except for Mark found his snap ring pliers which are slightly better than mine and did the job. These generators are 20 years old or more and some of the parts are not available. So you may have to improvise like I did with the 50 amp breaker. I also put new connectors on some of the wires that went to the other circuit breaker and the voltage regulator. Even though I bought a new voltage regulator I used the old one and that seemed to work just fine so I have a spare now. Unfortunately we couldn't get the generator all the way out as I didn't have time to mess with the exhaust system. It was rusted pretty good and I had broke one of the studs so at some point I'll probably want to pull it again replace the studs in the exhaust manifold and probably at that point replace some of the sensors like the oil sensor and temperature sensor. I also wanted to clean and powder coat the base and take the bearings out and clean them but that wasn't going to happen because the generator was still sitting on the tray. Which brings me to the last lesson I guess and that is to not start a job like this if you're in a hurry. The whole point of doing this was so that when I drive up to Oklahoma City with my ex-wife Julie that we would have reliable generator and air conditioning. I achieve that goal so I'm okay with it but I didn't do everything that I wanted to. Also the first set of motor mounts I have to return cuz they weren't the right ones even though they were the same part numbers that other people have posted. Shipping was an issue I probably paid over $200 to ship the bearing and other parts from power tec as well as the motor mounts which only had to come from Dallas but was quite expensive.
Hopefully you're not bored by now reading this long post and it will help somebody else that will want to try this as well. I suspect that I would have paid several thousand dollars at a generator shop to have this done. And I would have been deficient in the knowledge that I gained as well as what Mark gained in doing it.
I want to thank Mark, known as texhub here for his kind hospitality, knowledge, use of his tractor and driveway, and shower, and gallons of water that I drank. And also his wife Linda for putting up with me for several days. Their friendship will not be forgotten.

Some of my lesson learned.
1. Used fork lift attachment. Ran forks under pulled out generator. Placing forks between bottom of tray and cross bar at front.
2. Attached straps with ratcheting ability. This kept pull on generator as I lifted and pulled backward. Very carefully drove forward for reinstall. Humans can't push it when on forks.
3. The colored zip ties. I recommend as sop. MARK YOUR FUEL FEED LINE WITH YELLOW ZIP TIES. Use different colors on wires. Photo. This was gold standard.
4. Bleeding the lines. Just crack lines, 17mm. Takes seconds for bubbles, then fuel.
5. Expect metric, sae, straight slot, phillips.
6. Generator started normal, ran smoothly. Will recheck all lines again securely tightened.
7. We worked as a team. Bouncing ideas, facts, forum assistance. Safety was job 1. Bob suffered, cuts to many fingers. Lots of bad positions bent over gen. I recommend a bench to allow better body position. This was a in the dirt fix. Have container (s) for bolts, nuts, screws. Have stainless replacement bolts, washer, nuts.
Mark

Add a line #8 Take pictures at each step of disassembly, it has saved me many times.

I'm still a little fuzzy on the puller arrangement to get the exciter off.  I know you said that's the easy part but I can easily visualize getting the bearing off.  The exciter I am confused about.  It's probably because I didn't have the exciter stater pulled off on mine.  Also on mine the exciter has no bolt holding it in.  There are threads there but that bolt is long gone.... somewhere?  Makes me think my end bearing was already done once.  It would make sense as my gen a good many hours on it.  I think I'm going to tackle this.  I have everything I need and the bearing has just been sitting in a drawer for years now ;)  Thanks for the explanations and pics.  It REALLY helps.  I'll make a video and put it on youtube.