Kohler 5ECD Code UU

YYZRC

Same old story. Genny ran fine last night for an hour. Ran fine this morning for 20 mins. Prepping for lunch and the genny cranks and starts and dies right away. Does another crank cycle and same thing. It did spit a code UU at one point. 

I pulled the port side plug and it looks ok (one season old) but ordered some new ones anyway. Put the plug back in and she fired right up. 

🙄🙄🙄

Black_Diamond

5e’s eat plugs.  😂

Aqua_Aura

UU is under voltage

LaRea

Check the top left fuse holder (F1).  When my fuse holder failed, it gave the same symptoms you are describing.

https://rinkerboats.vanillacommunities.com/discussion/comment/96396#Comment_96396

YYZRC

Will check it. Good to have you back @LaRea

aero3113

@YYZRC , I had that happen the second time I used the generator this season. I thought it was because I didn’t have the battery charger on. I started it again and turned the charger on and haven’t had an issue since. Do I need to have the battery charger on? Or am I making myself feel good by having it on!?

YYZRC

The only AC breakers I turn off when not in use are the water heater, range and air conditioner. The others are always on. 

When I got the UU I tried different combinations of breakers including turning the range on (breaker and cooktop) but no dice. 

Black_Diamond

Did you order the NGK plugs?  I had zero luck with any plugs besides the NGK’s in mine. 

Are you getting seawater flow?  It will shut down fast if the impeller or coupler failed. 

YYZRC

Yes I ordered the NGK BPR4ES @Black_Diamond

Flow is good, new impeller last season. I think the genny is just underused (50 hours in 13 years). 

Black_Diamond

Good one on the plugs.  

50 hrs is super low. Once I got my 5e running, I ran it with load every week for at least an hour.  They need to run.  Never had issues afterwards.  It was an adventure to get it running though…lol

YYZRC

Yes, definitely low hours! Too low! I am doing my best to add

Spyderweb

@YYZRC what did you have on drawing power when you got the UU?

aero3113

Do both the 5E and 5ECD have similar issues with eating plugs?

YYZRC

Spyderweb said:

@YYZRC what did you have on drawing power when you got the UU?

I tried starting it with and without load. Normally I start it without load the first time (as the switch is set to shorepower) and then subsequent starts are with load. This time it didn’t matter, it just wouldn’t stay running. 

The manual says it will run for 10 seconds before it dies with UU but it wouldn’t even stay running. 

Black_Diamond

Have you checked your coolant level?  Need to check at the pressure cap and at the overflow bottle. 

YYZRC

Yep all good. 

Black_Diamond

Anti-diesel valve would be my next check. Pull and clean w/carb cleaner. 

YYZRC

Where is it exactly @Black_Diamond ?

Maybe a dumb question but could I disconnect the fuel line at the shut off valve and put the fuel hose into a gallon can of Sea Foam? Guys on my dock swear by the stuff and I’m tempted to give it a go. 

Alternately I could pour it into the cool fuel modules but that doesn’t help me with the genny. 

aero3113

@YYZRC
I just remembered!! My first season with my 330 I was getting a UU code. I was chasing electrical and it turned out it was the injector! 

aero3113

@YYZRC read through this. When I change the injector it starts on page 4.

https://rinkerboats.vanillacommunities.com/discussion/10623/kohler-5ecd-generator/p1

YYZRC

Do you remember the part # @aero3113

I believe my fuel wasn’t the best (boat sat for almost 2 years before I bought it) so it wouldn’t be crazy to think the injector is bunged up. 

aero3113

aero3113

Here you go

https://www.partsfortechs.com/index.php?main_page=product_info&products_id=2095

Black_Diamond

Partsfortechs is a great part place.  

The 5e is carburated. 

The anti-diesel valve: on the outboard side of the carb. It has a single wire running to it.  It just unscrews. The plunger at the end should move freely.  Carb spray it and the hole it goes into. 

You can feed it from a gas can: but because the 5e has a fuel pump you neec to run the hose from the gas can to the fuel pump inlet.  BTW: there is a screw in fuel filter at the fuel pump inlet. I got rid of mine and just put in a bronze hose barbed adapter.  I just used the small raycor bowl fuel filter up at the shut off valve.