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Onan MDKAL Generator Fuel Solenoid SM2000


Mike Ondra
 

Hello fellow Amelians,

Having an issue with the genset on SM2000.

After no use for 3 months, it would crank but not start. After 8 sec preheat, pressing START, engine cranks fine, but no ignition. Visual check confirms that the fuel shutoff solenoid is not moving to open position when START is engaged. When manually pushing the solenoid to open valve, starts fine. The valve remained open after release and ran fine for several hours. Normal shutdown. Then, to test, did the same procedure. Would not start until manual push on solenoid, but now does not stay in the open position.

This generator has only the cutoff switches for temperature and oil pressure, no gauges.

Perhaps someone has a quick explanation for the above from experience.

 

In the meantime, I am trying to figure out the control diagram to assist in troubleshooting. Here’s my logic so far.

The Start/Stop toggle switch functionally cuts off the fuel when pressed to the STOP position. In the START position it must energize the SOLENOID to open the fuel valve. The toggle then “defaults” to a neutral position in the RUN mode, so the SOLENOID must remain energized, but not through the switch or it would be continually energize even when off.

Furthermore, to protect the running engine, a fault in either oil pressure or engine temperature must de-energize the SOLENOID to cut off fuel. The pressure and temperature “senders” lead to a “2 pole double throw” switch which I presume has the capacity to de-energize the fuel cutoff solenoid when the “sender information” does not meet spec.

What I haven’t been able to ferret out is if there is an interface between the START function and the safety cutoff function.

Pressing the START should power the solenoid. Does the safety part of the system need to be “happy” during the start, or is it completely independent and takes over powering the solenoid only AFTER the engine starts?

Will continue the research, but would appreciate insight from other and  would like to know if my assumptions above may be heading me in the wrong direction.

Thanks

Mike Ondra

Aletes SM#240 Rock Hall, MD

 

 

 


Jose Venegas
 

Hi Mike,
When I bought the boat the previous owner told me that the generator needed to be preheated for at least 20 seconds. I do that every time and it starts every time. I hope this helps you.
Hi Mike,
When I bought the boat the previous owner told me that the generator needed to be preheated for at least 20 seconds. I do that every time and it starts every time. I hope this helps you.


Mark Erdos
 

It should be noted that in the Onan instructions and on the remote start
switch it states 20 seconds in the maximum for the pre-heat.


With best regards,

Mark

Skipper
Sailing Vessel - Cream Puff - SM2K - #275
Currently cruising - Tahiti, French Polynesia
www.creampuff.us

-----Original Message-----
From: main@AmelYachtOwners.groups.io [mailto:main@AmelYachtOwners.groups.io]
On Behalf Of Jose Venegas via groups.io
Sent: Monday, September 14, 2020 9:14 AM
To: main@amelyachtowners.groups.io
Subject: Re: [AmelYachtOwners] Onan MDKAL Generator Fuel Solenoid SM2000

Hi Mike,
When I bought the boat the previous owner told me that the generator needed
to be preheated for at least 20 seconds. I do that every time and it starts
every time. I hope this helps you.
Hi Mike,
When I bought the boat the previous owner told me that the generator needed
to be preheated for at least 20 seconds. I do that every time and it starts
every time. I hope this helps you.


Steve Bell s/y Dusk SM378
 

Hi Mike.
              Since we purchased Dusk and the  the previous owners have  had start problems with the genset .

They even had parrelled a smaller battery next to the genset which helped but in hindsight was not a good idea as the batteries were not the same.rating and the smaller battery was being overcharged so i was determined to try and resolve the problem.

I had the genset serviced and had the fuel.pump negative solenoid  terminal block all replaced  which seemed.to.fix the problem however within 24hrs i was back to square one.

The owner of the company who serviced the genset was extremely embarrassed and personally came out to try and find the problem. 2hrs later the problem seems.to be solved and bolied down to a faulty k3 relay for.the pre heat plugs as we are in the  meditterean he said it was not neccassary to pre heat the plugs with he present weather conditions  so he removed it and suggested i buy a new one when i got the chance he suggested to try and get a 70amp one as opposed to the present 30amp one

For 3.months we have not had a problem starting the genset with the realy removed whilst this may not be your problem it may be worthwhile removing the relay and trying it out.

We purchased a new relay for 7 euro


regards
steve
s/y Dusk




 

Mike,

Is it possible that you are talking about the Onan Governor, Actuator (new part #306−5006−01 old#151-0779-01), which increases rpm under load and shuts off when you press stop?

If you are, it is possible that the governor is bad, or the control board is bad.

I am not sure how to test other than to attempt to check voltage changes when pressing start or stop. If there are voltage changes the control board (PCB) is probably OK. There may be a fuse on the control board or in-line with the governor if you get no voltage. You should also see if the gov actuator opens up more fuel when load is added...if not, there is a problem with the actuator or PCB. The purpose of the Gov. Actuator is to maintain constant RPM, regardless of the load. This maintains a constant 50htz frequency.

I carried a spare but never had to use it.

Bill
CW Bill Rouse Amel Owners Yacht School
Address: 720 Winnie, Galveston Island, Texas 77550 
View My Training Calendar


On Mon, Sep 14, 2020 at 10:29 AM Mike Ondra via groups.io <mdondra=verizon.net@groups.io> wrote:

Hello fellow Amelians,

Having an issue with the genset on SM2000.

After no use for 3 months, it would crank but not start. After 8 sec preheat, pressing START, engine cranks fine, but no ignition. Visual check confirms that the fuel shutoff solenoid is not moving to open position when START is engaged. When manually pushing the solenoid to open valve, starts fine. The valve remained open after release and ran fine for several hours. Normal shutdown. Then, to test, did the same procedure. Would not start until manual push on solenoid, but now does not stay in the open position.

This generator has only the cutoff switches for temperature and oil pressure, no gauges.

Perhaps someone has a quick explanation for the above from experience.

 

In the meantime, I am trying to figure out the control diagram to assist in troubleshooting. Here’s my logic so far.

The Start/Stop toggle switch functionally cuts off the fuel when pressed to the STOP position. In the START position it must energize the SOLENOID to open the fuel valve. The toggle then “defaults” to a neutral position in the RUN mode, so the SOLENOID must remain energized, but not through the switch or it would be continually energize even when off.

Furthermore, to protect the running engine, a fault in either oil pressure or engine temperature must de-energize the SOLENOID to cut off fuel. The pressure and temperature “senders” lead to a “2 pole double throw” switch which I presume has the capacity to de-energize the fuel cutoff solenoid when the “sender information” does not meet spec.

What I haven’t been able to ferret out is if there is an interface between the START function and the safety cutoff function.

Pressing the START should power the solenoid. Does the safety part of the system need to be “happy” during the start, or is it completely independent and takes over powering the solenoid only AFTER the engine starts?

Will continue the research, but would appreciate insight from other and  would like to know if my assumptions above may be heading me in the wrong direction.

Thanks

Mike Ondra

Aletes SM#240 Rock Hall, MD

 

 

 


Germain Jean-Pierre
 

Hello Mike and Jose,

The PO was wrong. My MDKAL starts immediately without any preheat.

Find a Kubota dealer who has a roving mechanic...

Good luck

Jean-Pierre Germain, Eleuthera, SM007, NZ

On 15/09/2020, at 7:13 AM, Jose Venegas via groups.io <josegvenegas=icloud.com@groups.io> wrote:

Hi Mike,
When I bought the boat the previous owner told me that the generator needed to be preheated for at least 20 seconds. I do that every time and it starts every time. I hope this helps you.
Hi Mike,
When I bought the boat the previous owner told me that the generator needed to be preheated for at least 20 seconds. I do that every time and it starts every time. I hope this helps you.