Powermate Generator - Not Generating Power

hey guys welcome back so today I brought home this 5500 watt Powermate generator this is powered by a Yamaha mz-300 engine and I found it on Facebook Marketplace for 200 according to the listing the engine runs well but this generator doesn't make power and 200 bucks for a generator that doesn't make Power that's a lot of money so I offered them 100 and we agreed on 140 which I think is a good deal I mean these engines are well built and I've seen several with well over 1500 hours and they were running strong you know unfortunately I wasn't able to start this one the tank was empty and the seller didn't have any fuel so we could have issues there anyway worst case I have another generator with a blown engine that I think this one could go in its place but before tearing this thing down I I want to do some tests and just make sure that this power head is terminal so let me set up a little bit better and get going on this hopefully you can see the multimeter okay I've got it turned on and set to ohms now on 240 volt generators there are two main windings and usually it's wired in such a way that you have leg one on one set of outlets and leg two on the other but not always you know if there's any doubt you can use the 240 Outlet you have the ground here with this tab neutral then leg one and leg two so that's where I'm going to test and generally I see between 0.3 and 0.4 ohms and if you're not sure the reading should be consistent between leg 1 and leg two in this case we get point six point five that's a bit High you know I would expect it to be around 0.4.3 so it's not terrible but it is high check the other leg a little bit lower I got 0.5 so there is a slight difference between the two but not much so no red flags here I wouldn't say based on that that we have a bad stator so I'm gonna get the tank out of the way it's actually missing its Hardware so that'll be easy to just lift off and there is a quick disconnect back here I want to unplug that check it directly on the wires that go down to the stator that's also going to isolate it from ground so I can check each of the coils again to see if the reading is any lower because sometimes resistance can be introduced in the control panel especially on the circuit breakers so we'll eliminate that from the equation check it direct and see if see what we see foreign this connector has five wires there are two that are black and two that are white and the center one is green that is the ground wire so the way they usually wire this is that one of the legs is diagonal from each other and then the other leg is diagonal the other way so let's just do the same test and see if that resistance is any lower 0.4 0.3 that seems like a good reading check the other leg 0.4 0.3 so that's good leg 1 and leg two to what I'd expect them to be and they're consistent when testing directly down to the stator now since we have it isolated there's two more tests we can do first is we can check each leg to ground and make sure there's no connection so I can touch it to the engine or we can use this ground wire in the middle there's no connection to ground we'll check the other leg no connection to ground that's good the last test we can do is just check between leg 1 and leg two and that's like the ground test it's just making sure there's no failure in the insulation and we get nothing so it would actually seem like the stator is healthy on this generator so I'm inclined to think it does work potentially there are issues with the brushes or the rotor so let's take a look down on the end cap and see if we can't do any tests down there I don't know if this is brushed or brushless but if it is a brushed generator the brushes will be right behind here and yeah this is a brushed generator so let's get those screws out we'll disconnect the brushes from the AVR or actually in this case it's just a bridge rectifier and then we'll test the ohms through the brushes to the rotor foreign the brushes seem to be in good shape so I'm just loosely kind of reinstall them I don't actually want to connect them back to the bridge rectifier because that'll kind of skew the reading that I want to take now the rotor on this generator it should be around 30 or 35 ohms and when testing it through the brushes it is going to add a hundred maybe 200 ohms which is fine you know I just want to see that the rotor is not open circuit because that is typically how they fail you know they spin it 3600 RPM and the wires weaken and break so if I get any reading around 200 ohms or less I'll be pretty happy yeah it seems like a good reading 86 ohms let's check it to ground and there's a connection to ground so that that's the problem the insulation on the rotor failed and it's shorted to ground so there might be a chance with this one I do have I think one Powermate rotor I have no idea if it's compatible with this power head and the only way to find out is to uninstall this power head which has to be done anyway so let's get the stator off we'll get the rotor off and see if there's any chance of swapping that out with the one I have change of plan I'm going to start the engine before pulling the power head off I want to make sure that there's no surprises and there's plenty of oil needs to be changed but it's fine to test with that engine sounds great it started first pull and the carburetor is doing a good job so for once I may not have to clean that carburetor you know the seller did tell me he cleaned it out in order to get this generator running and that's when he realized it wasn't making power so I think we're good to proceed anyway before pulling that stator off I actually have to get the exhaust system off this one is kind of a unique design there is a bracket right here which is bolted into the core of the stator so until that's removed I'm not going to be able to get that power head out of there foreign foreign [Music] foreign hopefully this will do usually I slide a piece of wood under the engine to support it because once I get that end of the stator off you lose the support for the engine on that side anyway I've got the strap wrapped around kind of the bell housing so that should support this well enough so that when I get the stator off this won't flop and hit the floor foreign foreign foreign foreign why that stator wouldn't come off once I cracked the seal usually they slide right out but not this one I did have to apply leverage which you don't normally have to do but now I can see why you know this piece here is broken and clearly this was making some contact with the stator you know why I'm not sure you know potentially this data was just misaligned but my money would probably be on Rust you can see a bunch right here most likely that got caught between the rotor and the stator and just created some drag and you know this plastic piece just couldn't survive that so once it broke it allowed these wires to shift a bit and I'm sure the installation failed right in this area anyway let's get the rotor off [Music] I'm gonna do the easy thing here and just strike it with a hammer until it pops off the tapered shaft usually I don't recommend that unless it's a last resort because you can cause damage to that rotor and in this case the damage is already done foreign ERS on the left in the good spare on the right and you can see they look almost identical in every way except for one the good rotor is short by about half an inch so although the stator is good without the proper rotor I can't use it so I'm going to break out the other bad generator and see if I can't make too bad into one good this is the other broken generator in question it has a Subaru ex30 engine on it which through a rod and punched a hole in the side of the block so this engine is done but everything else on this generator is in very good condition including the frame itself which is a good thing because this one besides being weathered and having two flat tires I don't think is going to work with the stator on this generator because the mounting location for the stator is toward the back and on the Powermate it's actually more in the middle so as a result the cross member that supports the stator it's too far forward it needs to be further back in order for the good stator to work so this frames out this one's in the actual swap I think it's going to be pretty easy both of these are 300 CC engines they have the same tapered shaft same bolt pattern for the bell housing and I even think this one's going to drop onto the existing engine mounts without having to move them so it should be fairly straightforward but I do foresee at least two issues first the clearance on the air box is very tight on the Subaru and the Yamaha has a larger air box so that might be an issue in which case I will have to relocate the mounts and just slide everything back a couple inches to get the clearance I need the second issue and probably the bigger one is the exhaust system the one that came on here is pretty unsightly not to mention it mounts on the stator this stator cannot accommodate that mounting location so that is an issue I'm going to have to figure out I do have another Yamaha exhaust it's actually from a Yamaha clone of an mz360 which this is not this is an mz-300 so I don't know if it's compatible until I try so I'm going to break this one down in a very similar fashion we'll get the tank out of the way get the power head off only this time without using a hammer and start piecing together a working generator on this Frame foreign foreign foreign [Music] foreign foreign [Music] foreign thank you in this case I'm going to use a rod cut to size to push the rotor off it's fairly effective at removing rotors but you can't always use this method because the rotor bolt comes into diameters this one is an M8 which is fairly narrow it actually goes in the shaft and has a lot of slop which means you can use a larger rod to push against the tapered shaft and it won't damage the threads but some rotor bolts they are actually an M10 and there's no slop at all so the only Rod you can get in there is the same size and that will damage the thread so in that case I use water to build hydraulic pressure but this one don't need to do that so the idea is you just insert the rod this one's already threaded you want to make sure you can at least get a few threads to engage before it tightens up and now just torque down with an impact and that rotor should pop right off I was getting worried there for a second I thought I might be stripping the threads out thankfully it did release from the tapered shaft and the power head came off in one piece so I'm going to set this aside someplace safe and just continue on I want to get this blown engine out of the way but first i'm going to drain the oil no big clues in the oil it might be a little low it should have been enough to keep this engine running so I'm not really sure what led to this engine's failure my best guess would be someone ran it on a hill and either the oil sensor doesn't work or it was positioned in such a way that the oil went away from the Dipper but the oil sensor was still satisfied I'm not sure anyway let's continue foreign foreign [Music] foreign foreign it fits but only just I have the engine mounts installed Loosely and the air box the clearance on the bottom I'd say is acceptable but on the top it's touching the frame and that's going to Rattle make a lot of noise and potentially break that air box so I do need to slide the engine back a bit but I do need to be mindful of how far because the stator from the bell housing to the end it's 14 inches long and when you get to 15 inches it's up against that tire so I don't want to move it too much not to mention the wiring from the stator to the control panel may not have enough slack to do that so I'm going to shift this Maybe by a quarter of an inch or a third of an inch to the left and call that good foreign [Applause] thank you foreign plenty of clearance now it's better than the Subaru I think we'll be fine so I'm going to take a second just clean some of this stuff off and move on to that power head I've already loosened these State amounts I'm going to leave them here for now until the power heads installed then I can see exactly where they should go this belt housing also has to be swapped out I've already cracked these bolts loose so I'll get those off and put the correct bell housing on foreign [Music] foreign the bolts that were holding the Powermate on are pretty short compared to the Subaru and that is a bit of an issue because this bell housing here is quite a bit thicker and that bolt barely sticks through so I'm going to stick with the Subaru bolts they actually might be a bit too long if that's the case I'll just cut some of it back anyway I'm going to put some thread Locker on here usually they are held in place with thread Locker on the Subaru not really seeing any signs of that but the bolts that came out of the Yamaha definitely had some on there and it's a good safety measure I mean these should bite in anyway but that's just a little bit of extra protection foreign torquing this bolt down to 18 foot pounds I'm going to build a shoulder on it it's an eight millimeter bolt in diameter and the shaft is a little bit over 10 millimeters and as a result there's a lot of slop and when you torque it down it's going to go to one side which isn't a huge deal that's the way it comes from the factory but I think it makes sense to just build a shoulder with electrical tape while we're here to help center that bolt also the slip Rings you can see there's a lot of carbon buildup and it's actually hard to get a reading through all this I tested this power head before uninstalling it to make sure everything was good but this here very hard to get a consistent reading so I'm going to clean that up with a bit of scotch Sprite and then get that stator on foreign foreign foreign just make sure to watch out for these wires there's one on each side which connects the rotor to the slip rings foreign foreign foreign I just removed the spark plug so there's no compression I want to turn the engine over and listen I want to make sure that the rotor is not making any contact with the stator foreign [Music] thank you thank you foreign foreign it's a lot less hideous than I thought it would be so this I would say is an option but now that it's in place I can see there's a couple other issues at first the exhaust is a bit higher than I thought it would be and it's going to be maybe a little too close to that fuel tank but some of that is due to the fact that I can't actually drop it all the way in place the bracket is causing interference and you can see that stud there it's barely poking through so at a minimum I would have to cut some of that bracket away to allow this to drop into place properly so that I can bolt it down to the head and then get a little creative and somehow figure out how to attach that to the stator before doing that let's try this one this is the one from the mz360 Clone the mounting is different it actually attaches to the end housing there's a bolt hole here and I think the other one's right there the only catch is the length has to be exact so let's drop it in see if it has any chance of working foreign yeah this one's going to be perfect so I think I dodged a bullet on this one I'm going to clean out those bolt holes they are full of dirt and I'm going to uninstall the front of the heat shield I do want to paint that up but there's no reason I can't install the rest of the exhaust while doing that foreign [Music] foreign it's really close but I do have to elongate this hole just a bit in order to get that bolt to go in all right [Music] foreign unfortunately this bolt it's not going to work it's the right thread it goes in but the flange on the side of the bolts hits this housing and it can't actually make it to the bracket to clamp it into place so I've already checked my stash for a bolt without the flange with this thread and came up empty so instead I'm just going to use a nut as a spacer and that should be good enough to clamp down on this bracket this control panel was just barely holding onto the frame most of the screws were missing but one and I had assumed if I replaced the screws that everything would be okay but now that it's off I can see that is not the case this plastic back here it is cracked and everywhere a screw goes to secure it is also cracked and broken or just missing chunks so unfortunately this control panel can no longer be used in the way that it is but I do have a spare and it's essentially the same exact thing so I was going to go with this but there is one important difference this one has a quick disconnect unfortunately so I can't use this one as is but this plastic backing here looks to be the same part so I'm going to try to swap the backings so that I can make this one usable again foreign ER out foreign foreign foreign to the slip Rings it was very hard to measure any resistance through here so I'm going to swap out the wire block with one that's in better shape forgot the jumper wire this generator is bonded to the frame so the neutral needs to be connected to the ground although the Subaru engine had a low oil system it didn't have a low oil light like the Yamaha does so I pulled that light out of the old frame and a lot of times what manufacturers do is just bundle this up and zip tie it and let it dangle off the side of the block but I think you can do a little bit better than that I'm just going to drill a hole somewhere probably in this area and mount that light also need to do something similar for the ignition switch foreign [Music] foreign switch a try on the Yamaha I think it might be a better solution on this Frame instead of using that other switch yeah I think that's going to work out pretty well similar to where it was on the Subaru and a lot of Hondas and Honda clones put their switch there as well so let's get the blower housing off and get this switch installed that's not OEM I'm not sure what that is foreign foreign [Music] [Music] foreign foreign foreign I actually bought it for another project which I haven't started yet so I think I need to order another foreign double check the switch real quick the way the Subaru switch works is that it picks up the grounds from this screw here on the right that goes into the blower housing and when you flip the switch to off it passes that ground through this wire and then down to the coil so I just want to make sure that the blower housing is grounded well so I've got one lead connected to the engine ground multimeter set to test continuity I'm going to hold the other lead to the wire coming out of the switch and yeah that switch works fine so I'm just going to connect it up to the coil and we should be good foreign foreign [Music] [Music] [Music] foreign foreign foreign foreign I hope so I mean that power head it's unproven it came with a blown engine but I think based on the testing it should work So the plan is to get it started we'll check the voltage see where we're at most likely the AVR is going to need a small adjustment also I've got the multimeter connected to the 240 output that's just to verify I wired that properly because if I did it wrong I could have a scenario where I get 120 out but get nothing on the 240. so we'll double check that assuming everything is good we'll put it under a 5000 watt load and see if it can hold all right [Applause] [Applause] [Music] [Applause] a little bit hard to start but it did start and it ran pretty well I did notice the carburetor was flooding over and I think that's what the stuttering was at the end because when I turned the fuel valve off the engine smoothed out and ran perfect but when I turned the valve back on it started acting like it was running rich so right now I have it turned off we'll have to dig into that most likely we need a new needle but it had no issues really powering a load although it did give me a scare for a second I turned all of these on full which is actually 6 000 watts and the generator went to stall because this engine cannot pull that load it's only rated at 5 000 Watts so I backed that one off a bit and we were still pulling 5250 watts and the engine had no issues at all holding that that load and the voltage also is pretty much dead on so I don't think I need to make any adjustments there I think I can get that cover back on but I do need to drop the bowl on the carburetor and see what's going on with that needle and just to show you here you can see it's actively dripping I did shut the fuel valve off and the grass right there is going to be dead in about a week so yeah that bowl needs to be dropped and at a minimum that needle swapped out so let's give that a try just going to turn the fuel back on foreign yeah that needle is doing absolutely nothing and I'm killing all my grass got it needle doesn't look terrible although I do see that Ridge going all the way around so yeah that's probably the issue so we'll give this new needle a try and that should take care of this issue I see the problem the carburetor has a broken arm on the other side and that's why it couldn't seal properly so yeah although the carburetor runs the engine well it's not going to work so let me pull that off I just popped the air box off so you can see a little bit better the pin goes all the way through and there's two arms that hold that pin in place and that arm is broken off and not holding things in place so I do have a clone carb it looks brand new inside and the Yamaha clones usually run the engine pretty well so I'm going to pull that off put this in its place and we'll try this again foreign foreign [Music] [Music] the fuel turned on for about 10 minutes and this one is good it is not leaking at all so let's get it started we'll do the same test again real quick and just to make sure that this carb can run the engine as good as that other one that clone carb thankfully runs I would say as good as the OEM Mikuni and it figures the one time the seller actually cleaned the carb for for me you know I thought I was all set and in this case he was a little bit too rough and broke the arm off this carburetor so unfortunately this one is parts and this whole entire machine was made out of parts from four broken generators and in the end we've got one good one that's doing exactly what it should so I hope this video helped someone thanks for watching thank you

Channel: James Condon

Views: 149,933

Keywords: Alternator, Broken Leg, Brushed, Carb Clean, Clean Slip Rings, Control Panel Repair, Fixed, Flooding, Generator, Ground Fault, HU5000, Hertz, High Resistance, Homelite, How To, How-To, Insulation Test, Leaking Gas, Load Test, MZ300, Mikuni, No Output, No Power, PM0645500, Powerhead Swap, Powermate, Repair, Slip Rings, Small Engine, Stator Wiring, Sybaru EX30, Troubleshooting, Voltage Regulator, Volts, Yamaha, MZ360

Id: QEU3_l3Nqlg

Length: 82min 27sec (4947 seconds)

Published: Thu Feb 16 2023