5kw Generator

[Racinbob 11,039]

I picked up a 5kw generator at the big show. I'm mounting it now to make sure there are no snags. The pulley isn't the original one.  Can anybody tell me the diameter of a #107739 pulley?

[Achto 27,502]

1 hour ago, Racinbob said:

Can anybody tell me the diameter of a #107739 pulley?

I do not know the diameter of that pulley but I can tell you that if the gen is a two pole it will need to spin at 3600 RPMs to make 60Hz. If it is a four pole it will need to spin at 1800 RPM's. I would think that it would be a two pole gen, in that case the pulley on the gen would be the same as on the engine. Is there an RPM rating on the gen tag?

Edited July 11, 2016 by achto

[WHX?? 48,760]

Ahhh..... Bob....ahem cough cough .... you know the drill.....  I can run home at lunch and measure mine!

 

Edited July 11, 2016 by WHX7

[Racinbob 11,039]

1 hour ago, achto said:

I do not know the diameter of that pulley but I can tell you that if the gen is a two pole it will need to spin at 3600 RPMs to make 60Hz. If it is a four pole it will need to spin at 1800 RPM's. I would think that it would be a two pole gen, in that case the pulley on the gen would be the same as on the engine. Is there an RPM rating on the gen tag?

I know it's 3600. I'm mainly just curious as to the original diameter. Right now it has a 3 3/4" pulley and would take a 61" belt. The specified belt, #107740, is 63". I will set this up so I can back off from full throttle a bit. Hopefully I will get it the way I want it the first time so I only have to buy one belt.

 

44 minutes ago, WHX7 said:

Ahhh..... Bob....ahem cough cough .... you know the drill.....  I can run home at lunch and measure mine!

 

I'll snap a couple right after I finish lunch.

[Achto 27,502]

Not sure what your mounting it on but keep in mind that you need 1.5hp per kw. So if you only have an 8hp engine it might not be able to pull full load at a lower RPM. Just something to consider.

[WHX?? 48,760]

How do you know how many poles it has Dan?? is it stamped on the data plate?

[Racinbob 11,039]

Actually the industry standard is 2hp per kw. I've got is on a 15hp tractor. I went ahead and made the trip to Tractor Supply. I picked up a 3 1/2" pulley and a 61" belt. I'm liking the pulley size but I probably will swap the belt for a 60". Tried her out and I'm getting voltage swings but the afternoon heat had me crying uncle so I just parked her in the barn. But not before taking these.

[Achto 27,502]

If there is nothing on the data plate or the plate is missing you would have to remove the end cover and count the rotor poles. If the plate states that the gen RPMs should be 3600 this would mean that the gen is a two pole. Most small gens use a two pole to keep manufacturing price down. Until inverter technology Onan's were popular on board gens for campers because they used a four pole gen & kept the engine RPMs down to 1800 for less noise.

[WHX?? 48,760]

That hot down there Bob?? Balmy 87 here today!! Go get some more of that ice cream!!  Btw nice tractor there Bob but the way yer grass looks you can leave the deck off!

 

Sounds like you are the Genny pro Dan, you work for that place in Oshkosh that makes them?

Edited July 11, 2016 by WHX7

[Achto 27,502]

21 minutes ago, Racinbob said:

Actually the industry standard is 2hp per kw

Not being impolite but 1.5hp/kw is the true requirement. Example 3kw gen will have a 5hp engine. The 2000kw gen that I'm running right now at 2008kw has a 3100hp engine.

 

Just now, WHX7 said:

Sounds like you are the Genny pro Dan, you work for that place in Oshkosh that makes them?

Yep 12yrs testing & R&D with 3kw - 2000kw generators.

[WHX?? 48,760]

Cool T&J right?? I did the HVAC work there in a new weld shop where they were fabbing frames many years ago.  I also have one of their small 3k units that I got out of R&D cause they were done messing with it.

Not to steal Bob's thread but anything you can tell me about this one,  two pole, four pole?? It came with a 520 and I haven't had time to mess with it yet but from what you are saying it may need a different pully. Th PO never used it either and it came with the 2 brackets in the pic, I believe the one on the left mounts right on the front attach. No idea what the bracket on the right is for.

I always  figured it might com in handy building deer stands out in the woods.

I'll have to get a close up of that plate.

Keep us posted on the voltage swings thing Bob

[gwest_ca-(File Mod) 11,031]

RPM 3600 stamped on the plate.

 

Garry

[squonk 41,018]

On my Generac  3000 w 3600 RPM (WH genny on homemade plate) I run an AX64 (Notched 66" X1/2") belt. Pulley is 4 1/2" OD

 

Edited July 11, 2016 by squonk

[Racinbob 11,039]

2 hours ago, WHX7 said:

That hot down there Bob?? Balmy 87 here today!! Go get some more of that ice cream!!  Btw nice tractor there Bob but the way yer grass looks you can leave the deck off!

 

Sounds like you are the Genny pro Dan, you work for that place in Oshkosh that makes them?

 

Mid 90's Jim with the humidity at 4 gazillion. This old boy just can't take it like I use to. That was taken in the back under a live oak tree. Nothing likes to grow under them things.

[Achto 27,502]

4 hours ago, Racinbob said:

Tried her out and I'm getting voltage swings but the afternoon heat had me crying uncle so I just parked her in the barn.

Voltage swing is usually do to unstable engine speed, assuming that this is not the problem here's some thing to try. I'm going to guess that your gen voltage is regulated by a capacitor. This type of regulation can be a little unstable with no load, 10 volts each way. Try putting some load on the gen and see if it stabilizes. My favorite at home load bank is a 1500w space heater, the old tin box style with a rheostat to control the wattage. A two piece toaster is about 800w, or a couple of 100w incandescent bulbs . Don't try any thing with a digital control, electronics don't always get along with this style gen. Sensitive electronics were not an issue for engineers to deal with when these were made.  If the voltage stabilizes with load then I would not be too concerned about the no load fluctuation. If you still have a large voltage swing you may need a new capacitor. Let us know how it goes.

[Racinbob 11,039]

I'll get back on it Wednesday morning. I have a hunch the voltage regulator is bad. The fluctuations I was getting won't be solved by a load and engine rpm fluctuations wasn't the issue. If I'm right the good news is that they are still available. The bad news is that they are pricy. I have a couple more things I want to check out and then I'm going to tear her down and go through it. Not a real happy camper at this point.

[Achto 27,502]

4 hours ago, WHX7 said:

Cool T&J right?? I did the HVAC work there in a new weld shop where they were fabbing frames many years ago.  I also have one of their small 3k units that I got out of R&D cause they were done messing with it

 

2 hours ago, gwest_ca said:

RPM 3600 stamped on the plate.

T&J was before my time I came in under Baldor's ownership, then ABB until they decided to get out of power generation, and now Generac's name hangs out front. As far as your belt drive gen you'll have to get the gearing right to achieve 3600RPMs. Unfortunately the mounting brackets are usually made by the purchasers, the gen leaves with just the plate on the bottom.  You'll most likely have to figure out how to fab that together. There is a slight possibility that your gen may have lost residual voltage from sitting for a long period of time. If you have no voltage after you get it mounted you may have to flash the gen with a 12v battery to bring it back. Doesn't always happen but it can. If you have any issue when you get that far let me know. 

[Wildhorse 298]

Nice setup Bob! One of my future projects is to get a generator too.

[Achto 27,502]

17 hours ago, WHX7 said:

 

Kind of looks like the bracket on the left mounts to the tractor and the bracket on the right mounts to the gen. Then may be the one on the right mounts to the one on the left as a kind of quick release.

[Achto 27,502]

On ‎7‎/‎11‎/‎2016 at 9:22 AM, Racinbob said:

I picked up a 5kw generator at the big show.

Say Bob, was that gen made by Generac? Do you have a wire diagram for it? If it was and you don't have a diagram shoot me the a pic of the id tag and I'll see if I can find one in our archives.

[Racinbob 11,039]

Thanks but I have the Wheel Horse owners manual as well as the Generac manual with the wiring diagram. I've been tied up the past two mornings on other projects but tomorrow i plan to get back on it. With the heat we've ben having unless I absolutely have to I don't even try to work out in it during the afternoon.

[Achto 27,502]

Under stand the heat thing, we got a little break today other wise it's been hot & muggy. Good luck with the project. If you need parts let me know, no promises but I can check to see if I can get them.

[Racinbob 11,039]

Thanks.I don't want to jump to conclusions because there's more troubleshooting to do but if it is the regulator I did some research and found out a Generac 063180 AVR will replace the obsolete 42541 with a couple of wiring mods.

 

[Racinbob 11,039]

@WHX7  Jim, no worries about stealing my thread. That thing is a beast. Look how heavy that cover is compared to the later models. Built when they really did things right. You would want to match the pulley to the pto pulley if you want to run wide open. For starters I'm using a 3 1/2" pulley. Rather that guesstimate I finally broke down today and ordered a mid-range laser tach so now I'll know where I'm at.

[WHX?? 48,760]

Yeah I'd love to get at my genny project Bob, right after a good general clean up on her, install pedal kit, ventilate belt guard, carb cleaning... . Like I said the PO never used it and it came with the tractor when he got it from the PO'S PO!! Also came with a milk crate of belts that don't really match up with anything so I think po was just cleaning out his garage on me!. 

Using Dan's 1.5 hp per kw calculation I don't think I will be/have to running WFO on it but the cooling fan is part of the genny pulley so that one may have to stay as is. Either way I have lots of tinkering to do. Let us know/start a thread in tools on that  tach you got and how it works out...that tool is on my wish list as well.

25 minutes ago, Racinbob said:

Look how heavy that cover is compared to the later models.

Yes my end bells are cast iron  instead of AL, may need to put a set of wheels under it like Mike did for moving it around!