Bl**dy Mikuni

[Biggles]

My Mikuni MX60 has devoloped a rather anoying problem:-

 

The fuel pump won't start, so remove I make up a temporary connection to the control module bypassing the set wiring and it works put it back on the set wiring and it works.

 

Next morning no start. So do the same again and it starts. Next time it doesn't etc. SO I rung Mikuni and they sent a replacement pump fitted that same problem, sent control module back, it was tested and found no problem but changed the board anyway, refitted, same situation.

 

Has anyone seen the same issue and found a resolve.

 

Oh and NOT interested in the I told you not to buy a Mikuni, Ebber, etc. so no comments of that sort will be useful, just a waste of bandwidth,

[jelunga]

I do not have a mikuni but an Eversplogger. It works in the sequence of:-

Water pump

Air pump

Glow plug

Fuel

 

If any stage fails it shuts down.

I had problems at the air pump stage.

Due to lots of carbon dust in motor and cold damp mornings causing tracking in the air motor and no start.

Sometimes it would sometimes it wouldn't.

Cleaned up motor, checked all cabling ok and not dropping too much voltage and it works again ( for the moment anyway).

Spect Mikuni works in a similar fashion. Could it be these cold damp mornings causing electricity leaks?

[ridders]

hi biggles, looking through other stuff someone had a similar problem which turned out to be a fuel shutoff solenoid, does yours have one?

paul

[Biggles]

The unit is fairly new. Probably less than 100 hours hard use.

 

The sequence is exactly the Salem. The fuel solinoid is workig, I have tested the fuel pum supply and it is outputting voltage to the pump. If it was a ba connection to the pump it will shut down. Found this out when I disconnected the pump. If Needs to be in circuit.

 

As for leccy leaks whilst it is cold, the unit is to t all damp, and let's face it they are designed to work when it's cold.

 

My Webasto on my BMW is 10 years old and never fails to start when the outside temp drops to 3°. It's never been service to my knowledge.

[mrsmelly]

hi biggles, looking through other stuff someone had a similar problem which turned out to be a fuel shutoff solenoid, does yours have one?

paul

Hi Biggles

 

I had the mx60 on my last boat. A very quick hetaer of both water and central heating though quite tempremental. I had it serviced by mikuni and a new brain and water pump ( I can save you money on that if you ever need one ) But I asked an auto electrician what to do ( He had never seen one !! ) He did a mod and removed a bit of the kit now I am sorry I cant show you it cos I have sold the boat but it was seperate to the main unit and I think it was something to do with regulating the voltage to the glow plug. Ok I know its not your glow plug but once this mod was done I never had one single problem with the unit and it may tie in to the fuel pump I suppose

Hope this may help but I doubt it

[smileypete]

My Mikuni MX60 has devoloped a rather anoying problem:-

 

The fuel pump won't start, so remove I make up a temporary connection to the control module bypassing the set wiring and it works put it back on the set wiring and it works.

What do you mean by the 'set wiring' exactly???

 

cheers,

Pete.

[blackrose]

I told you not to buy a Mikuni, Ebber, etc.

[sebrof]

I told you not to buy a Mikuni, Ebber, etc.

 

Sound advice, Blackers.

[Biggles]

What do you mean by the 'set wiring' exactly???

 

cheers,

Pete.

 

The wiring that came on the manufactured loom, as opposed to the temporary wires I scotch locked in to get a better place to do the testing. The pump is in an awkward place.

 

Hi Biggles

 

I had the mx60 on my last boat. A very quick hetaer of both water and central heating though quite tempremental. I had it serviced by mikuni and a new brain and water pump ( I can save you money on that if you ever need one ) But I asked an auto electrician what to do ( He had never seen one !! ) He did a mod and removed a bit of the kit now I am sorry I cant show you it cos I have sold the boat but it was seperate to the main unit and I think it was something to do with regulating the voltage to the glow plug. Ok I know its not your glow plug but once this mod was done I never had one single problem with the unit and it may tie in to the fuel pump I suppose

Hope this may help but I doubt it

 

It is a good heater when it works.

[Naughty Cal]

The unit is fairly new. Probably less than 100 hours hard use.

 

The sequence is exactly the Salem. The fuel solinoid is workig, I have tested the fuel pum supply and it is outputting voltage to the pump. If it was a ba connection to the pump it will shut down. Found this out when I disconnected the pump. If Needs to be in circuit.

 

As for leccy leaks whilst it is cold, the unit is to t all damp, and let's face it they are designed to work when it's cold.

 

My Webasto on my BMW is 10 years old and never fails to start when the outside temp drops to 3°. It's never been service to my knowledge.

 

We have a Webasto air heater on NC (Airtop 2000ST) and it has never failed us. It is about 8 years old now and has to our knowledge never been serviced. It just plods on and on and on. One of the air fans is starting to get a little noisy and ready for replacing but at £6 for the new part we can hardly complain. Might strip it down and give it clean whilst we have it out but it is going to wait until Spring when we are not so reliant on it before we mess about with it

[WotEver]

Might strip it down and give it clean whilst we have it out...

Don't, you'll break it.

[smileypete]

The wiring that came on the manufactured loom, as opposed to the temporary wires I scotch locked in to get a better place to do the testing. The pump is in an awkward place.

OK, so what connection do you make to the control module?

 

Trying to understand if you're driving the pump directly or overriding something in the control module.

 

Best I can suggest is see if there's a fault diagnosis chart/table in the installation module and follow it as logically as possible.

 

Failing that take it out, set it up on a bench with a decent fully charged 12V battery (and fuse) right next to it and connect to a tank of water. If it works fine it could well be an install issue.

 

cheers,

Pete.

Edited December 16, 2011 by smileypete

[14skipper]

I think my Mikuni MX60 is bloody great (water system is shit ) but my Mikuni is great.And as its christmas any unwanted Mikis will be a rehoused. Remember a Mikuni is for life not just for ............

 

14skipper

[Biggles]

Ok here's the problem.

 

Fuel delivery. For some reason I have a reduced flow of diesel from the tank. This was arrived at by a very long day on the phone at regular intervals to Mikuni customer support which I have to say is first rate.

 

To establish this I set up a tempoary tank of diesel and it ran perfectly. So the problem is either the electronic fuel valve or a blockage in the very short boss into the tank, or as hard as it might seem a blockage in tank, but seeing as how the tak is new and it's only had fresh diesel in it I do wonder.

 

So now I have to drain the tank and take the electronic valve out. Messy.

[steve hayes]

Ok here's the problem.

 

Fuel delivery. For some reason I have a reduced flow of diesel from the tank. This was arrived at by a very long day on the phone at regular intervals to Mikuni customer support which I have to say is first rate.

 

To establish this I set up a tempoary tank of diesel and it ran perfectly. So the problem is either the electronic fuel valve or a blockage in the very short boss into the tank, or as hard as it might seem a blockage in tank, but seeing as how the tak is new and it's only had fresh diesel in it I do wonder.

 

So now I have to drain the tank and take the electronic valve out. Messy.

 

Slightly off topic, we had issues with deisel feed on a previous boat, engine would start and run easily when the tank was over half full, but was a pig to get started when the tank was emptier. We looked for blockages, air leaks, etc. kept thinking we found things but to no avail. Eventually it was found to be a hole in the fuel pickup pipe.

 

How full is your tank?