Author Topic: Speed/Governor Issues  (Read 21319 times)

KellyR

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Re: Speed/Governor Issues
« Reply #15 on: February 15, 2010, 01:49:19 AM »
The generator is an ST3 wired for 120v.  I still have the doghouse on it and put a 20 amp breaker in it, along with a plug for the generator wire.  That wire then goes to another plug on my power shed.  From there it's to the AC panel.  I've got a single, Outback inverter and 8 - 6v batteries at 24v for 760 amps total. 

After my last message, I went back out and tried it again, using my portable breaker box and the kill-a-watt meter.  I fine-tuned the governor to run at 61 hertz at no-load.  Voltage was still around 137.  At this point, I connected a 1.1kW load, which decreased the hertz slightly, but not too much.  Voltage also dropped slightly.  As for the engine, no change.  I then connected the generator to the power shed outlet and got it to start charging the batteries.  No error light this time.

Two things, I think I was too impatient.  THis time I waited until the engine had run for a few minutes before trying to adjust the governor.  Then, I spent more time adjusting the governor to be "just right" rather than "I guess that's good enough."

The engine has not been run often or for long.  I suppose there's perhaps 30 minutes total time on it at the moment.  See my other threads about cooling and fuel.  I'm still not quite happy with my setup, but those things that I want to change are fairly easy.  One is to get the Utterpower-style governor on it.  It blows black smoke when first starting, but clears up very quickly.  When I put the load on it, there was very little change in the sound of the engine and NO change in the color of the exhaust.

Stan

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Re: Speed/Governor Issues
« Reply #16 on: February 15, 2010, 03:49:34 PM »
My manual (1949 6/1 came with the engine) states in caps

"THE SPEED MARKED ON THE ENGINE MUST NOT BE INCREASED BY MORE THAN 2 1/2% WITHOUT FIRST CONSULTING US.".

I'd guess this is to keep people from mucking about without knowing what they are doing, but I wonder if it has something to do with the timing of the fuel pump discharge, changing with different speeds? 

I'll let some of the more knowledgeable diesel guys answer this, as I'm just a lowly aircooled VW guy.  :-[
Stan

KellyR

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Re: Speed/Governor Issues
« Reply #17 on: February 15, 2010, 04:06:29 PM »
I'm certainly not overloading the engine.  I was more concerned about it lugging.  My inverter can only handle 20 amps.  Since I've got the generator wired at 120v, the most that the inverter can pull is 2400watts.  That's not going to overwork the engine, even at my elevation (6400feet).  My inverter seems to be okay with the voltage being off.  It seems not to like the hertz being off though.

Stan, have you tried hooking a VW engine to a generator?  even one of the old 1200cc single ports would allow you to run a pretty big generator.

Stan

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Re: Speed/Governor Issues
« Reply #18 on: February 15, 2010, 05:10:53 PM »
Yup, thought about it lots.  Air cooled, no radiator, relatively cheap, easy to fix,  but it doesn't sound like a Lister.  ???
Stan

ronmar

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Re: Speed/Governor Issues
« Reply #19 on: February 15, 2010, 09:52:16 PM »
Unless you are measuring the voltage and current to the load and know the power factor of the load, you don't KNOW that you are overloading the engine...  I would guess that inverter/charger is a fairly inductive load(switching power supply?).

What temp is the engine operating at? 

Again, troubleshooting is just guesswork with so many unknowns.  This thing YOU built is supposed to do something, but untill you actually measure it, how do you know it is performing as advertised?

I say put together a couple of 500W and 1KW plug in electric heaters.  Measure the voltage and current applied to these to establsh a known electric load.  If using plugin heaters, you can move teh killowat around to total the loads individually.  Then you will know what it is capable of, or where it falls on it's nose.  The load bank will also give you the opportunity to break in the engine properly.  Get it up to op temp(around 200F at the cylinder head coolant outlet IMO) and Put 2+ KW of electric load on it for several HOURS.  This will also test your cooling system operation so monitor it closely.

I don't recall the derate per 1000FT, but i would say 2.5KW will be the upper end of your load capacity.  It is also the breaker limit you have set for it anyway.

Can't get it to hold 2KW of measured load?  Now you KNOW you have an engine issue.  One key area to look at is the sliding yolk/fork where the linkage attaches to the fuel pump rod/rack.  If this dosn't slide freely, it could be binding as the governor wants to increase the throttle.  This was the worst part of my governor assembly... 
PS 6/1 - ST-5.

Stan

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Re: Speed/Governor Issues
« Reply #20 on: February 16, 2010, 12:49:47 AM »
Each engine is slightly different but Lister engines usually are rated at 4% lower power output every 1000' above 1000', AND 2% lower for each 5 deg C above 25 deg C.

http://www.dayliff.com/pidiefs/Lister.pdf

Stan

ronmar

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Re: Speed/Governor Issues
« Reply #21 on: February 16, 2010, 04:49:57 AM »
Each engine is slightly different but Lister engines usually are rated at 4% lower power output every 1000' above 1000', AND 2% lower for each 5 deg C above 25 deg C.

http://www.dayliff.com/pidiefs/Lister.pdf

Stan

Thanks Stan, that would make 2.5KW about right for 6400'...
PS 6/1 - ST-5.

BruceM

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Re: Speed/Governor Issues
« Reply #22 on: February 16, 2010, 05:19:03 AM »

"One key area to look at is the sliding yolk/fork where the linkage attaches to the fuel pump rod/rack.  If this dosn't slide freely, it could be binding as the governor wants to increase the throttle.  This was the worst part of my governor assembly... "

I second Ronmar's advice- same location my governor was binding, I had to bush the arm that the yoke is supposed to slide up and down in to get it to move freely without binding. 

59Hz to 63Hz for full range of load is pretty good for the governor on an engine at 6000ft on a 6/1.  (I'm near that.)



Stan

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Re: Speed/Governor Issues
« Reply #23 on: February 16, 2010, 10:37:23 PM »
Each engine is slightly different but Lister engines usually are rated at 4% lower power output every 1000' above 1000', AND 2% lower for each 5 deg C above 25 deg C.

http://www.dayliff.com/pidiefs/Lister.pdf

Stan

Thanks Stan, that would make 2.5KW about right for 6400'...

Is it a radiator model?

If not, you'll lose not quite 1hp for altitude, that gives you 5hp (assuming everything else is perfectly balanced, tightened etc. etc.   General rule is 2kw per hp. so that works out to 2.5kw.  If you are running a fan for a radiator count on losing a third of a hp more.
Stan

KellyR

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Re: Speed/Governor Issues
« Reply #24 on: February 17, 2010, 01:28:09 AM »
I've got a honda goldwing radiator with electric fan, though I'd like to switch it for an oil field engine radiator with a belt-driven fan.  It's still butt cold here (got the 9 last night), so I'm not running it with straight water.

I chose the 3kW ST because the engine would run it at my altitude without over loading.  I suppose I could run a 5kW, but what would the point be since I can only draw 2.5kW through my inverter anyway?

There are some more adjustments I'd like to make to the assembly, but I'll keep folks apprised on what happens.  I'm going to try to borrow a heater to put a load on the gen/engine without hooking it to the power panel.

Jim Mc

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Re: Speed/Governor Issues
« Reply #25 on: February 17, 2010, 02:50:13 AM »
Anyone have any suggestions for keeping the rpm of the engine constant at 650 so that my gen spits out 60hz? .



Yes.

The basic tweak is to remove the original governor spring and replace it with a longer, weaker spring.  You'll need to modify the fixed point mount by moving it away from the governor to allow the spring to be stretched to a greater length. 

Very simple.  Very effective.


KellyR

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Re: Speed/Governor Issues
« Reply #26 on: February 18, 2010, 01:35:27 AM »
Hey Jim,

Fixing the governor ala utterpower is on my to do list for tomorrow.  I'll have access to a metal shop then.  It will definitely be easier to fine tune the engine speed with that.

My only real concern at this point is with the generator itself.  As I mentioned, with no load the hertz came in at 61, but the voltage was a bit high--around 137.  If I decreased the voltage to 120, then the hertz reading went down to about 57.  Anyone know why this might be the case and what to do about it?

Jim Mc

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Re: Speed/Governor Issues
« Reply #27 on: February 18, 2010, 02:54:52 AM »
How did you decrease the voltage to 120? 

And exactly what problem are you trying to fix?  the too-high no-load voltage?  The drop in frequency?  The drop in voltage?


KellyR

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Re: Speed/Governor Issues
« Reply #28 on: February 18, 2010, 02:58:01 AM »
I adjusted the governor to decrease the engine speed.  That lowered the voltage and the hertz reading.  It would be nice if I could get the generator to run at 120v and 60 hertz.

KellyR

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Re: Speed/Governor Issues
« Reply #29 on: February 18, 2010, 03:23:24 AM »
Someone asked about wiring a while back.  I just checked inside the doghouse of the generator.  U2 and U6 are tied together and U1 and U5 are together.  Each of those has a wire leading to the outlet/breaker and there is ground wire.