Jeta Power 15kw generator connections

[mskobier]

All,
I am new to this group, and have read many of the pior posts. I have a Jeta Power 15kw three phase generator that was manufactured for the military in 1961. The military designation is MD-151815-WA, and the FSN NO. 6115-617-4919. The generator package only has 1540 hrs on the original Jeta Power hour meter. The generator "package" was designed for three phase only. The generator head is a GE type SJ 12 wire. In studing the documentation that came with the generator, it appears that the genreator can be re-connected for 240/120 single phase. I have been able to determine that it will have to be configured as a Low Zig Zag or Double Delta. I think the best option is to configure it as a Double Delta. Of course, I have not been able to find any information on the pro's or con's of either configuration. The problem I have found in searching the net is that there seems to at least a couple different "standard" connections for these configurations. Does anyone have any information on this type of generator head? Can anyone educate me on which is the best configuration, Low Zig Zag or Double delta?

Also, the engine is a Hercules D-198 diesel that runs great, but it does not have any type of glow plug system. It starts well down to about 50 degrees, then I have to use the ether system that was designed for it. I would like to locate some type of intake manifold heater so that I do not have to use the ether and can set it up for remote starting. I have considered using the intake manifold air heater from a Dodge Diesel pickup truck. Does anyone have any experience with retrofitting an air heater to these engines? I use this generator most every day to top off the storage batteries that I run the shop off of during the cloudy winter. It also supplies power to the shop while it is running. Any and all help/information on the generator/engine will be greatly appreciated.

Thanks
Mitch

 

[jdunmyer]

I have a 1994 Dodge Cummins Turbo Diesel truck, and that manifold/air heater works really well. It does require some extra "throttle" for those cold starts, the colder, the more I have to press on the pedal. It sure seems possible that you could retrofit that heater outfit onto your Herc.

The Dodge heaters are configured as TWO independant elements, each powered by its own relay. You can get 12-volt Ford-type starter relays at NAPA or such places that are probably cheaper than the Dodge relays, not to mention probably more reliable in the long run. (although I've had no trouble with mine) Those heaters also cycle on and off after the engine starts, until it begins to warm up. You can see it on the voltmeter and hear the engine bog down a bit.

 

[Jim McIntyre]

I've also got a 15 kW mil surplus genset with a D198. Shortly after I got it, we had a spell of -20F weather. On a whim I decided to see if there would be any way to get it started. It cranked for a few seconds and started up with no problem. I was really surprised.

I keep a good set of batteries in it - I wonder why the difference in starting your set. Maybe just the age and time, though 1500 hours isn't very much. Not sure what your ether system is like, but the one in mine is electrically operated, and could be remote controlled. (Well, if it worked, that is - it's never worked and I've not looked into the trouble...)

I've left mine set up as 120/208 mainly out of laziness, but it operates all our 240V loads just fine. Good question about double delta vs. low zig-zag. Some of my EE books on generators say that delta connections, in general, are best avoided, since they will allow harmonic currents to circulate - creating some extra heating in the stator windings. Other than that, though, I am not aware of any advantage of one connection over the other.

 

[Elden DuRand]

The Dodge heaters are configured as TWO independant elements, each powered by its own relay........... You can see it on the voltmeter and hear the engine bog down a bit.

I've got a motorhome with a '92 Dodge Diesel engine. I'm impressed by how easily it starts in cold weather with the electric intake heater. When I put an ammeter on the rig, I found out that the heater draws nearly 100 Amps when it's on. No wonder the engine bogs down when the heater cycles!

When it was really cold, I would use a 1200 degree heat gun stuck into the intake manifold to start the 4.154 Perkins in my '50 Chevy. If it was left there for a minute or so before cranking, the engine would start "trying" or cranking fast almost immediately and usually about 10 seconds of that would heat the pistons 'til it would go ahead and run enough so I could disengage the starter.

Take care - Elden
http://home.cybertron.com/~edurand

 

[mskobier]

All,
Thanks for the replies. Jim, The ether system in mine is a hand pumped affair. You are supposed to open a chamber place an "ether egg" in it, puncture the egg and hand pump the ether into the intake while pushing the start button. The manual specifies the <50 degree F starting temp. It has started at lower temps without ether. I have a friend who is an ex-diesel mechanic who thinks the engine timing is retarded. He thinks this due to the engine sound and the smell of the exhaust. I know the injector pump was rebuilt/replaced in early 1990 by the previous owner, and it was hardly ever run after that. The injectors still have the military green paint on them and do not look to have been replaced. I am considering having them checked/rebuilt at the local injector rebuild shop. As for the injector timing, I have not yet been able to locate the timing procedure for this engine. I think there is a timing mark on the flywheel and some sort of mark on the injector pump in an inspection window. Does anyone have the injector pump set up directions for this engine? I also think part of the starting issue is that it is 44 years old and was in standby service and probably never saw a good hard load. As soon as I get a few things sorted out, I will put as large a load on it as I safely can, and let it run for a day. That should clean out any carbon build up. I'll also use some of the stuff they use on marine engines that you spray into the cylinder and let soak to dissolve any carbon buildup. My friend and I used it on a three cylinder diesel generator we found in the scrap yard that had low compression and was hard to start. Two treatments and it was starting a lot better and running much better. Again a victim of low loads for extended periods of time.
As for the current load of the electric air heater, on my engine, I have discovered that once it fires, it will continue to run without any problems. So the high current load would only be for a short period of time. Of course I could change the charging system to a 24v alternator to provide the necessary power for powering it when the engine was running. It still has the original generator and it works fine for now.
Again, thanks all for your responses.

Mitch

 

[jdunmyer]

Mitch,
If you decide that ether injection is acceptable, there's an alternative to that old "egg" setup. I installed a KBI (I think that's the name) kit on the Case engine on my sawmill. Mine is solenoid operated, but you can get them in a Bowden wire configuration also. The starting fluid comes in a can that looks exactly like the one used on your propane torch. The orifice that's in the intake manifold is sized to your engine. You load the metering chamber by pressing the button or pulling the knob (Bowden wire), then releasing it. The fluid is metered into the manifold at a controlled rate, so you don't damage the engine. Injection is ONLY done while the engine is cranking, of course!

You can see some pics of the KBI setup on my sawmill page.

http://www.oldengine.org/members/jdunmyer/sawmill

 

[Raymond]

You would be doing your engine a big favor and also eliminate the hard starting by installing a block heater. A 750-1000 watt unit should be all you need if enclosed. keep it between 90 and 105 deg. and it'll crank and pickup load like a hot summer day. It will also eliminate condensation on the inside which occurs every time one cools off and goes through temperature cycles that reach below the previous several days dewpoint. My 1969 D198 Hercules Bogue 15 KW unit has a capped 1/2" port in the side of the pan, and one up around the thermostat housing where I will be installing mine when I get off my butt. Mine starts great even below freezing but I'm worried about moisture damage. mine has around 650 hours on it. It smokes white running unloaded but 2 KW clears it up. I've had good luck timing the Rosa's by setting it to where it runs the quietest at idle when warm. You can then try 2 or 3 degrees each way, starting cold the next day to check. Be carefull with the injection line fittings on the pump. If you twist one you'll be very unhappy for a long time.

 

[mskobier]

All,
Thanks for the replies. I got to play with the engine some more over the holiday. I have discovered I can get the engine to start down to about 30 degrees F. Any lower than that and I need to get the ether out and give it a small squirt. Once it fires once, its takes off and runs fine. I agree that a block heater would be the best solution, but I do not have permanent power where the generator is located. I will primarily be using it to keep the storage batteries charged up and provide power when I'm working in the shop. When the generator is not running, I run off the Trace sine wave inverter for all lights and power tools. During the summer, the generator will not be used as much due to the solar panels being able to keep up with my usage. During the winter, we do not get a lot od sun, so the generator is necessary. The reason I was considering the intake manifold heater is so I could set up a remote start system for the generator. Its not necessary, but it would be nice. Anyway, thanks again for the info.

Mitch

 

[enginenut2]

Mitch,I have another suggestion for a cold start aid.I have had much experience over the years with Perkins engines and their use of a simple device made by Lucas called a Thermostart.It's made like this:the Thermostart is a cartridge about 2" long with male threads about 1" od that threads into the inlet manifold usually near the center.This cartridge has a small heating coil in the center with a shield around it and holes in the shield.It extends about 1 1/4" into the manifold and exterior to the manifold it gets a 1/4 inch line hooked inthe middle and a approx #12 wire connected to a lug that will be energized with battery voltage.Works like this:crank the engine about 5 seconds to build fuel pressure,energize the element for about 15 seconds and keep it energized then get back on the starter and away she goes.The line hooked to the thermostart is piped into the fuel supply before the injection pump but can't put fuel into the thermostart unless the coil is heated which opens a ball check,fuel flows over the incandescent coil and starts a little fire in the manifold heating the incoming air.IT WORKS.Go look at Massey Furguson tractors for an example.More later.

 

[enginenut2]

OK I'm back.I supervised the vehicle maint shop in an industrial plant and we had many various engines in cranes,fork truck,welder,manlift and earthmoving equipment and with operators of varying degrees of skill and caring,cold weather brought many challenges.The earlier perkins with indirect injection like your Hercules were not excellent cold starters, but there are things that help.Cranking speed is most inportant on any diesel and the proper selection of lube oil viscosity has a great bearing on it if you don't have a sump heater.Some talk of diesels getting addicted to starting fluid but I say they had a engine that was sick anyway and the fluid just let them get by a little longer but ether use with glow plugs or manifold heater in use can cause minor explosions and temporary incontenance to the user and observers.Ether of course should be used sparingly and with the engine rolling over as fast as possible.I have retrofitted these thermostart to john deere and case with good results and Mercedes uses a similar system hooked to a computor control on many industrial applications,cycling it on and off after the engine was running to cut smoke during warmup.Our big 14 litre v8 had two of them, one on each bank.I talk too much.Good luck

 

[Elden DuRand]

The Perkins 4.154 engine in my Chevy had the thermostart and it worked well. Took a little getting used to, though.

When it was really cold, I'd crank for about 5 seconds with the injectionb pump cut-off to build pressure to the thermostart. I'd quit cranking and fire up the thermostart 'til I heard the "ploop" sound of the fire starting in the intake manifold.

Immediately, I'd start cranking with the fuel still off. Once the engine started trying to start (cranking fast) from the fuel in the manifold, I'd slowly turn on the fuel (via a "choke wire"), being careful to not to it too fast. (If I turned the fuel on too fast, my theory is that the large amount of fuel delivered to the injectors would cause an evaporative cooling effect that would stop the partial ignitions.)

The engine would crank faster and faster as I turned on the fuel 'til the engine was running.

It only took about ten years to learn this practice.

Take care - Elden

 

[Jetter]

All,
Thanks for the replies. Jim, The ether system in mine is a hand pumped affair. You are supposed to open a chamber place an "ether egg" in it, puncture the egg and hand pump the ether into the intake while pushing the start button. The manual specifies the <50 degree F starting temp. It has started at lower temps without ether. I have a friend who is an ex-diesel mechanic who thinks the engine timing is retarded. He thinks this due to the engine sound and the smell of the exhaust. I know the injector pump was rebuilt/replaced in early 1990 by the previous owner, and it was hardly ever run after that. The injectors still have the military green paint on them and do not look to have been replaced. I am considering having them checked/rebuilt at the local injector rebuild shop. As for the injector timing, I have not yet been able to locate the timing procedure for this engine. I think there is a timing mark on the flywheel and some sort of mark on the injector pump in an inspection window. Does anyone have the injector pump set up directions for this engine? I also think part of the starting issue is that it is 44 years old and was in standby service and probably never saw a good hard load. As soon as I get a few things sorted out, I will put as large a load on it as I safely can, and let it run for a day. That should clean out any carbon build up. I'll also use some of the stuff they use on marine engines that you spray into the cylinder and let soak to dissolve any carbon buildup. My friend and I used it on a three cylinder diesel generator we found in the scrap yard that had low compression and was hard to start. Two treatments and it was starting a lot better and running much better. Again a victim of low loads for extended periods of time.
As for the current load of the electric air heater, on my engine, I have discovered that once it fires, it will continue to run without any problems. So the high current load would only be for a short period of time. Of course I could change the charging system to a 24v alternator to provide the necessary power for powering it when the engine was running. It still has the original generator and it works fine for now.
Again, thanks all for your responses.

Mitch

i have model-D1568M fsn-2c-6115-880-1944 hoping someone could tell me the timing marks that line up on pump and the marks on flywheel for no. 1 cylinder or should no. 3 be used?? also where can i get a manual for this machine(not making but 5-8 volts) and nothing on the 120v plugs.hope someone can help. Thanks again!

 

[mskobier]

All,
Its been a while, but I finally figured out the wiring to convert my Jeta 15KW three phase generator to single phase and actually work like it is supposed to. First, the generator is now wired in what is called Zig Zag, however, the standard Zig Zag as listed in all the references does not work. The reason is the voltage regulator senses the voltage across phase number three. Which in Zig Zag is in series with phase number two. The two phases are in series and the resulting output is the sum of the two phases. What I had to do was wire it so that phase number three was by itself and configure phases one and two so that they were in the correct phasing to get the expected output. It is very important to get the phases in the correct order. Because if you do not, you end up with a much lower output due to the phases being 240 degrees out instead of 120 degrees. Anyway, it works like a charm. I finished the wiring, started it up, set the voltage from the front panel, checked the voltages with a digital volt meter, then applied a 7kw load. The genrator held steady at 120/240 volts and the engine stayed right at 60hz. Can't ask for more than that! Anyway, I thought the group would like to know I finally figured it out. I still have the either system. For now, it works fine.

Mitch