John Deere Z930M

bertsmobile1

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Correct pump ?
Your engine uses an impulse pump and they are all interchangable.
Check you have it plumed properly.
The top hole is for the impulse line from your engine
the tube nearest it is the intake and the one on the opposite side is the outlet.
There is a check valve in the outlet so if it is backwards it will not work.

Now IF you are willing to do what is asked we might be able to fix your problem.
OTOH if you are determined to race out and replace parts willy nilly I will go somewhere that I can be more helpful.

You said the carb is not getting fuel, 'How did you come to that conclusion ?
Are you sure that the fuel is being delivered from the fuel tank ?
Dose this model have twin tanks ?
If yes is the tank turned on ?

If it is a single tank, can you siphon fuel from it ?
If not try blowing back through the fuel line and see if it makes any difference.

Have you tested the fuel system as I previously asked ?
 

Breezytwo

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Correct pump ?
Your engine uses an impulse pump and they are all interchangable.
Check you have it plumed properly.
The top hole is for the impulse line from your engine
the tube nearest it is the intake and the one on the opposite side is the outlet.
There is a check valve in the outlet so if it is backwards it will not work.

Now IF you are willing to do what is asked we might be able to fix your problem.
OTOH if you are determined to race out and replace parts willy nilly I will go somewhere that I can be more helpful.

You said the carb is not getting fuel, 'How did you come to that conclusion ?
Are you sure that the fuel is being delivered from the fuel tank ?
Dose this model have twin tanks ?
If yes is the tank turned on ?

If it is a single tank, can you siphon fuel from it ?
If not try blowing back through the fuel line and see if it makes any difference.

Have you tested the fuel system as I previously asked ?


Hi Bertsmobile, are you into cars by chance maybe hot rods or modified cars? I just finished restoring/modifying a 1953 Ford f100 that had a fuel delivery problem, turned out that that the mechanical fuel pump which runs off the cam, as I'm sure you know, was bad and then the first replacement was also bad but three times was a charm and the 351Cleveland now runs good. Had a similar problem with a '67 Ford Mustang, the gas tank had to be over half full for it to run, as the fuel pump was bad but with the help of gravity it would run fine up to a point.

Back to the mower problem, to answer your first question, yes the Kawasaki fuel pumps are the same in principle but the connections are different depending on the specific engine and while I thought that the FX Kawasaki engines would all use the same fuel pump, they don't, the two bolts that attach to the engine are located differently making the the line attachments a problem. To answer your second question regarding the carburetor not getting fuel, simply by taking the line from the fuel pump to the carburetor off and cranking the engine several times with no fuel running out. At the same time there was gas on the inlet side as the fuel filter was full of gas, it just was not being sucked into this vacuums fuel disperser (that they call fuel pump). To answer your third question the JD 930M has only one fuel tank located on the right side facing the mower from the front. This tank holds about 11 gallons and has two lines coming from the top, one that sends gas to the fuel pump through a fuel filter and one that runs directly into the carburetor housing which I assume (one should never assume anything)is to equalize the pressure. I see no fuel shut off valve and again assume the solenoid on the carburetor shuts off the fuel and keeps it from flowing into the crankcase. I am a newbie to Z turn commercial mowers and am stumped as to what is or is not going on with my new uses 900 hours JD.
 

bertsmobile1

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the second line is the vent for the tank ( Cal EPA requirement ).
Just because the filter has fuel in it dose not mean there is a fuel supply.
The impulse pump is very weak and only pumps around 7 to 10 psi so if the outlet is blocked it can not suck it through.
Double check the fuel pump hook up to make sure the outlet is not connected to the inlet.
Confirm you have fuel to the pump by sucking on the line ( yum ) and allowing the fuel to syphon out.

IF you have fuel to the pump then you should be able to suck fuel through the pump by sucking on the line at the carb end.

Did you take the float bowl off ?
was it empty or full ?
 

Breezytwo

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The mower has fuel in the carburetor bowl, there is spark to the plugs, the engine cranks fine but it will not start. The fuel pump is working the carburetor solenoid is working it just will not start. It was running fine and then starting cutting out and after parking would not start. I suspect some safety feature but with no manual don't know what to look for. Oh, I only see one inline fuse and it's ok.
 

bertsmobile1

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Well you are obviously no slouch when it comes to engines.
Mower engines are exactly the same as car engines and follow exactly the same principles.
If your plug is not wet after cranking for a while then there is no fuel getting into the engine.
that means either the valves are not working as they should or the fuel is not getting out of the carb

To eliminate one or the other
1) drop some fuel , starter fluid down the plug hole and crank the engine
Engine fires & runs a few seconds = electrics OK valves are sealing the cylinder.

2) spray some starter fluid through the carb & crank the engine.
Engine runs on starter fluid = valves are working & carb is not

3 Remove the carb but leave the fuel line & solenoid connected.
Turn the engine on and blow over the emulsion tube with compressed air.
Fuel sprays out = carb and solenoid functioning correctly
Fuel does not spray out, remove solenoid and try again ( hold your thumb over the hole to keep the float bowl on )
Fuel sprays out = solenoid not working

4) replace carb, remove bowl crank engine while working the float .
Fuel dribbles/ pours out & cuts off = float valve & fuel supply functioning OK.
Fuel drips out = fuel supply blockage.
Fuel does not stop = defective float valve.

Don't let it confuse it.
The governor is just a cruise control
everything else works exactly the same except for the decompressor.
 

Darryl G

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The mower has fuel in the carburetor bowl, there is spark to the plugs, the engine cranks fine but it will not start. The fuel pump is working the carburetor solenoid is working it just will not start. It was running fine and then starting cutting out and after parking would not start. I suspect some safety feature but with no manual don't know what to look for. Oh, I only see one inline fuse and it's ok.
I don't think it's a safety feature. They may prevent it from turning over or cause it to stall when the parking brake is disengaged or the PTO is actuated, but if it's cranking I don't see how it can be a safety switch.
 

bertsmobile1

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The mower has fuel in the carburetor bowl, there is spark to the plugs, the engine cranks fine but it will not start. The fuel pump is working the carburetor solenoid is working it just will not start. It was running fine and then starting cutting out and after parking would not start. I suspect some safety feature but with no manual don't know what to look for. Oh, I only see one inline fuse and it's ok.

There are very comprehensive technical manuals available for every thing John deer ever made, including the ride ones.
They are by far the best mower manuals ever printed.
They assume the owner has never seen a ride on before so tell you the theory about how each part works , exactly where the part is hidden on the mower then go into a step by step detailed account of how to diagnose your mowers problem.
Not just a flow chart, proper instructions, push this in , pull that out sit on seat turn the switch to ??
Down side is they are around $ 40 as a digital download and closer to $ 100 as a paper copy.
he parts diagrams are also available on line , for free but you can only print 1 page at a time
And according to the Z930M diagram your wiring has a fuse, 2 x relay & diode.
There is also an engine control module fitted to some

Back in post 13 I asked you to confirm that you can get a fuel supply from the tank.
I am yet to see an answer to this.
I also asked for the same thing in an earlier reply.
In order for fuel to get out of the tank, air has to get in (or the tank implodes )
ZTRS kick up an enormous amount of dust and having the engine AND FUEL TANK behind the deck are prone to injesting lot of dust and that is before all of the other detritus that seems to be attracted to the big filling holes.
Good chance the outlet of the fuel tank is plugged which is why, way way back I asked you to blow back down the fuel line, this will temporarly dislodge a plug in the fuel line.
I also asked you to see if you can suck fuel through the fuel line which we are yet to see an answer to.
Fuel in a see through filter means nothing unless you can see it flowing.

One set of safety switches prevents the engine from cranking and another set prevents the engine from sparking.
You said your engine did both so there fore the safetys are not nor never were a problem which is why they were never mentioned.

Electrical system break down http://jdpc.deere.com/jdpc/servlet/com.deere.u90490.partscatalog.view.servlets.HomePageServlet_Alt

I have done the best I can for you
Good luck & good bye
 

Breezytwo

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Thanks for all your help Bertsmobile, I did get it started finally the main problem was the governor linkage. Now it will start and runs somewhat, looping and dying, but that I will fix. Oh, sorry you didn't understand my answer, the first thing I did was make sure is was getting gas and noting stopping it from the tank to the carburetor. I removed the carburetor and found nothing in the bowl and cleaned the jets anyway. Long story short, the main problem has been the governor linkage not opening the throttle, something I should have caught earlier but removing the carburetor made it obvious. There is also a shop manual for the Kawasaki 801V engine online that is very useful probably more so than any John Deere manual I have seen. Anyway, thanks again for your help, you are real asset to this forum.
 

bertsmobile1

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Always a problem having nothing but words on a screen and not being there on the spot to see, hear & smell what is gong on.
Then there are subtle differences in how people describe things.

The important thing is your mower is running, that is what the forum is all about.
Thanks for the compliment, I am just one of many that make this the best repair forum I have ever seen.
It was good before I got here ( yes I went back through the entire archive ) and will remain so when I go.

Don't mix up the JD owners manuals ( about 50 pages ) with the JD service manuals ( about 300 pages) .
Easy to do as the JD owners manual has more technical details than many service manuals.
I first bought one 3 years ago to fix a Diesel and was very impressed.
I bought another to repair another with an Onan engine ( never seen one of them before ) and found their engine manuals better than the engine companies manuals.
Over the years I have bought 5 and acquired another 4 and have no problems with buying more they have saved me hundreds of hours and from them I have derived my trouble shooting methods .
 
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