How to repair that old Kohler 5E...

[boatereng]

How to repair that old Kohler 5E Generator:

Our 2006 Sundancer 280 came with the original Kohler 5E generator which after only one hour on the water stopped working. The hour meter had only 75 hours but it certainly has many more judging by the old white paint and some rust. Compression in both cylinders is still good. But the generator would only start for 2-3 seconds then stop. To see the LEDs for troubleshooting, one needs to remove the lid of the control box, detach the control board (remove 5 screws), lift above cables, and attach again vertically face on to prevent it touching the box which keeping the cables attached. LED 4 didn't lit after the initial 2-3 seconds, so no sensor was activated. For access to the side plastic cover and air filter you need to drain the fresh water tank, detach the hoses, front and side brackets and move several inches to the port side. After removing and opening, the air duct was almost full with disintegrating old foam, perhaps the original foam air filter in front of the metallic mesh filter attached to the carburetor air inlet. Clean thoroughly the air duct from the foam. I have installed instead a fine wire mesh behind the coarse wire mesh filter. Carburetor is mounted with only two 10 mm bolts and easily can be detached. Clean it and make sure main jet inside the fuel chamber and the idle jet beneath the short front tube (pull it up after removing the screw) are very clean. I used stainless cable strand for cleaning. After re-assembly the generator ran but was hunting and then it stopped again. Since I have noticed some debris in the fuel, the fuel pump was the prime suspect. Changed the pump ($21 on Amazon Prime, received next day), replaced and then adjusted again the idle speed screw on the top of the carburetor and the governor speed control at the front. If working out of the water, make sure to use some large jar filled with water supplied by a garden hose. I have installed a multi-turn valve that allows me to fine tune the water flow to match the consumption from the generator. Unlike Westerbeke, Kohler is using a 16 HP Kawasaki engine with built-in mechanical governor to control RPM. There is still an electronic feedback but is is only for safety shutdown, not for RPM control. As long as the generator provides the 12 V after LED 5 is lit and no safety sensor is activated, it will run. For carburetor-re-assembly I cut my gaskets from hard grey paper made for gaskets and use non-hardening Hylomar Blue gasket maker, resistant to fuel and oil. Change oil, oil and fuel filters, change zinc, detach and flush the heat exchanger to clean from former raw water impeller debris, use good fuel, clean the strainer etc., the usual stuff.

Handymen and handy-ladies, good luck! I hope I have saved you countless hours searching online how-to and many $$$.

[clowenthal]

I find I have to replace the carburetor every 3 years or so because of the ethanol. Other than that she runs like a beauty! Appreciate the tips - they can certainly come in handy!

[Brite_Idea]

I bought a ten year old boat last summer with the Kohler 5E it only had about 55 hours on it. It wouldn't stay running for more than a few minutes at a time. My mechanic checked it out and said it was up to date on software upgrades and that I should just keep running it and it would get better. I start the generator when I get on the boat and run it for an hour every time I use the boat. I will say that at first I had to keep resetting it using the rocker switch on the generator but after about five hours of run time it finally works like it should. I'm hoping that after I commission it all will be good. Generators need to run so if it's mechanically ok and the software is up to date? You need to run it!

[boatereng]

What software, Kohler 5E is a very simple combination of general purpose 16 HP Kawasaki engine and a generator with electronic (but not computerized) regulator and control circuit that contains several relays needed to stop the engine if some of the sensors signals bad condition that can destroy the engine. Unlike Westerbeke, there is no even electrical throttle and electronic RPM control. It simply relies on the built-in centrifugal mechanical RPM control. Just like any engine, regular runs for a few minutes help lubricate it. Indeed, it is better to run until it reaches the operational temperature so the thermostat opens and the coolant circulates the full loop for awhile. The front of the heat exchanger left from the control box should get quite warm. Your need to reset is not normal and indicates a problem with the generator or the electrical system that is loading it.

[Phil_n_Nauti]

Try replacing the impeller

[boatereng]

Looking how much the generator "pees" is among the first thing to do every time when it starts. Changing the impeller on 5E is again a bit tricky but mandatory when you receive it with the boat - rarely one can have a confidence when was the last time that impeller was changed. The four bolts holding the lid a way too long and as is installed on Sundancer 280 there is no enough space to remove the bolts and the lid. So one has to remove instead the two bots with hex pan heads holding the entire pump. The problem is that the impeller housing is too close. I had to cut off one hex wrench short elbow to make it fit. Overall not a great design. Sorry Kohler, in my experience Westerbeke makes better generators although they also have some flaws.

[SamFisher]

I have a 2015 350 SD with a kohler 5EKD...don’t know if this is essentially the same model but am having problems with multiple shut down codes...under volt...air flow etc...generator runs 15-30 minutes and shuts down...the engine seems to run unevenly (rpms) just before it shuts down...it’s indoors at the marina and they are going to sea trial it for a diagnosis...any additional input on this would be most helpful!

[G_Michlig]

I had the same issue last summer a d went through most of what you did with the same results. Then I dig in a bit further behind the impeller and found the drive sleeve was shredded, so the impeller wasn’t turning and the generator wasn’t receiving water. Ran like a champ after replacing.

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