H3011H only runs when starter is engaged

fordperf

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I have a H3011H that only fires when the starter is engaged. It fires but only runs as fast as the starter will allow. As soon as I let go of the starter, it dies. It feels like it gets spark while the starter is engaged, but no spark when letting off the starter. This had me thinking it was something positional, or some kind of sensor that may be actively killing the spark while in run position.

Potentially related, months ago I had issues with it not recognizing the parking brake was off, and when I released the parking brake and put it into drive the alarm would sound. I disconnected the grey connector that controls that under the seat, and was able to drive normally and mow. However I noticed just with this recent start/run problem that even with the parking brake off and the mower off, the mower does not roll--the back wheels seem locked. I had to drag it around in the shed it would not roll at all.

I dont know if 1) the brake is somehow broken and permanently stuck on; or 2) there is a sensor that is reading this 'brake on' situation as a reason to kill the ignition during run (I cant think of a logical reason for this).

I know the 3011 has a bunch of sensors that could go bad--I'm open to any ideas!
 
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fordperf

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Forget the parking brake issue, I stupidly forgot to disengage the transmission release lever which I actually knew was there because I had released it years ago for something else. Me 0, mower 1.

I also ordered a new ignition key switch off ebay and working on getting a new combination relay from somewhere. The combo relay seems to be the root cause of many 'will not start' issues on the 3011, I am especially concerned with the ignition relay inside not working to run the ignition coil OR possibly I have burned out my ignition coil. Tho since the engine seems to fire when the start is engaged I took a gamble that the ignition coil is working but the ignition relay isnt engaging long enough.
 

bertsmobile1

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Don't beat yourself up about it.
Have any Idea how many times I get called out to fix a
"I ran out of fuel & now it won't start " job only to find the PTO is still engaged.
I used to waste time asking questions but found from a PR point of view best to drop by sort it out as a freebie ( for existing customers ) then choof off.
 

fordperf

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Thanks man. The mower is at a cabin in the middle of nowhere several hours from me, so when I make a trip out there to mow the grass it's like a one day committment at least. And when stuff doesnt work, it just shoots the whole trip plan to crap.

My folks bought the H3011H in 1990 for I believe $1700 used. It's a 30 year old mower! It's gone through a few belts and we put tubes in the tires, but it has run faithfully and we try to keep it maintained. But things invariably break over time. The sensors, the combo relay, etc. In the attached pics you can see less than half of the area to be mowed. Right now I didnt mow it for a year, the grass grew to 10 inches, flopped over and kept growing heh. Some of the pricker weeds are 5 feet tall. It's a lot for this mower to handle, it's only a 11hp motor on it.

If I cant get it running reliably it may just be time to upgrade. Looking at a Cub Cadet XT2 LX46, but I am not rushing to spend $2500 lol

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bertsmobile1

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Ok to start from the top.
Your engine has a magneto ignition which is self energizing.
The key switch grounds out the coil to turn the engine off and goes open circuit to allow the engine to start & run
A relay is just a switch that is controlled by another switch ( or series of switches )
I do not have a circuit diagram for your mower.
However all mowers have 3 circuits
1) cranking circuit
2) ignition circuit
3) charging circuit

When you split them into these 3 fixing it becomes a lot lot easier.
The cranking circuit will go from the battery ( generally a take off from the battery cable to the starting solenoid to save wire ) througn the key switch, through the PTO switch throuhg the brake switch and if you ae a mechanical gearbox, through the Neutral switch then to the trigger wire on the starting solenoid.
This is a daisy chain so if any one of these switches remains open the mower will not crank.

The ignition circuit
This is a series of parallel circuits that will ground the magneto and kill the engine
usually
PTO + seat switch ( So you can not chop your own hand of foot off by clearing the deck chute with the blades spinning )
Seat Switch + Brake switch ( so you can not run over yourself if you fall off )

During cranking the set switch is out of the circuit but once you let the key return to run, it is in circuit so if the seeat switch thinks you are not there and the brake seat thinks the brake is not on then the magneto gets grounded & the mower turns off.
If the carburettor has a fuel shut off solenoid then you can remove the kill wire from the magneto and use the furl shut off to kill the engine.
However this is not a safe mannar to run the mower in but it might get you out of trouble.

On lesser mowers the seat switch & brake switch have 2 sets of contacts so the start & crank can be separate circuits for the brake and the seat can have 2 separate circuits, one to the PTO & the other to the parking brake.

On this model these switches are single pole switches and the cleaver stuff is done in the very expensive relay housing.
Yours sounds like it has seen better days'\
Usually they are just a few individual relays and some diodes and can be fixed if you can follow smoke trails.
Otherways it is new relay box or rewire the mower.
Both of which are worth doing as this is a very good mower.
Wat wat better than anything you will pay less than $ 5,000 for now days.
The caveat will be condition of the rest of the mower in particular how much rust there is.
 

fordperf

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Ok to start from the top.
Your engine has a magneto ignition which is self energizing.
The key switch grounds out the coil to turn the engine off and goes open circuit to allow the engine to start & run
A relay is just a switch that is controlled by another switch ( or series of switches )
I do not have a circuit diagram for your mower.
However all mowers have 3 circuits
1) cranking circuit
2) ignition circuit
3) charging circuit

When you split them into these 3 fixing it becomes a lot lot easier.
The cranking circuit will go from the battery ( generally a take off from the battery cable to the starting solenoid to save wire ) througn the key switch, through the PTO switch throuhg the brake switch and if you ae a mechanical gearbox, through the Neutral switch then to the trigger wire on the starting solenoid.
This is a daisy chain so if any one of these switches remains open the mower will not crank.

The ignition circuit
This is a series of parallel circuits that will ground the magneto and kill the engine
usually
PTO + seat switch ( So you can not chop your own hand of foot off by clearing the deck chute with the blades spinning )
Seat Switch + Brake switch ( so you can not run over yourself if you fall off )

During cranking the set switch is out of the circuit but once you let the key return to run, it is in circuit so if the seeat switch thinks you are not there and the brake seat thinks the brake is not on then the magneto gets grounded & the mower turns off.
If the carburettor has a fuel shut off solenoid then you can remove the kill wire from the magneto and use the furl shut off to kill the engine.
However this is not a safe mannar to run the mower in but it might get you out of trouble.

On lesser mowers the seat switch & brake switch have 2 sets of contacts so the start & crank can be separate circuits for the brake and the seat can have 2 separate circuits, one to the PTO & the other to the parking brake.

On this model these switches are single pole switches and the cleaver stuff is done in the very expensive relay housing.
Yours sounds like it has seen better days'\
Usually they are just a few individual relays and some diodes and can be fixed if you can follow smoke trails.
Otherways it is new relay box or rewire the mower.
Both of which are worth doing as this is a very good mower.
Wat wat better than anything you will pay less than $ 5,000 for now days.
The caveat will be condition of the rest of the mower in particular how much rust there is.
The mower is in great shape as are the accessories (mulch kit, bagger). The only reason I am spending this much time on travel and diags is because the mower is a champ when it works. I wish I had pics of the mower to share, I have pics of every other damn thing lol.

Regarding the cranking circuit: since my motor does in fact crank over, is it safe to assume that all the safety switches are in fact properly closed? Could they be damaged-closed?

I didnt think the starter would turn over if the PTO switch was open (engaged) so I assume because the starter engages that the PTO was properly disengaged. The mower has a seat switch which worked last I knew; again it would not engage the starter if that seat switch was broken, so I assume that works too for the same reason as the PTO. Same with the brake switch. So because the starter cranks, I assume the PTO, seat, key, and brake switches are all closed. One might be broken, but it broke closed instead of open (if that's possible).

I do not know if it has a fuel cutoff solenoid. It has a manual fuel cutoff lever on the carb.

I bit the bullet and ordered a new combination relay for $130 as well as a new rectifier and key switch. I plan on immediately replacing the combo relay and rectifier, but since the key switch seems to be functioning I will hold off on that.

I will also check the fuse first, because like a dummy I forgot to look last time. I also picked up a new plug.

I appreciate all your help!
 

fordperf

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I watched some videos on bypassing the combo relay using an external switch, but I know that also bypasses the safety features. The terrain is rocky and hilly and frankly falling out of the seat is an actual possibility, I would rather not be run over by my own mower. If replacing the combo relay and rectifier do not solve my problem I may consider the bypass but I would rather not. People other than myself use the mower and I cant risk not having the safety features.
 

AVB

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If I am reading the schematic coorectly ( very blurry on the copy I got) you should check to see if 12v is present Black/Yellow wire at the ignition switch when it is in the run and start positions. If not present in the run position it would indicate a bad ignition switch.
 

bertsmobile1

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Number 1 rule
Check everything assume nothing.

All of the switches appear to have only one pair of contacts.
If that is the case they will be simple on off switches so you can connect a meter to the terminals then work the switch plunger.
Every time you depress the plunger the meter should change.
Check the seat switch by getting on ^ off the seat , check the brake by turning it on & off, same thing with the PTO switch.
Do it a couple of dozen times, If it fails to work on any single occasion then the switch is worn out,

If all f the switches are working properly then all that leaves is a broken wire or a broken relay or ignition switch.

I can not be any more specific than this because we did not get that mower down here so I can not get a wiring diagram for it.

Usually the switches are a ground circuit but when a master relay module is used then can be either a power or a ground circuit.
 

AVB

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Honda H3011H Wiring.PNG
 
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