Kohler 5ECD Not Running EC62, UU, UF

jmauld said:
Do you have any idea why mercruiser and Kohler did not do this in their design? Is there a safety issue/requirement that prevented it?

Edit: speaking with someone else, they think they did this to keep the fuel in the tank from heating up on an extended trip.
Click to expand...
That is exactly why in the automotive field, vehicles have returnless fuel systems and have for quite some time. Fuel pressure is controlled by the ECM which reads the fuel rail pressure sensor and then in turn, controls the fuel pump driver module which controls fuel pump speed.
 
On the Mercury larger OB's and Mercruiser the fuel system is returned to a small reservoir via the fuel pressure regulator. It isn't "returnless" in the true sense. For Mercruiser they incorporate a cooling feature to that little reservoir hence "Coolfuel". I suspect in the case of Mercruiser that there are so many types of fuel tank systems on so many different boats that they opted for the self-contained fuel management system. In this form they have control on the fuel pressure and flow rates.
The diesel powered boats all return fuel to the tanks so in retrospect I don't know why Mercury couldn't establish specifications for use of their products.
 
I rented a fuel pressure gauge today that had an angle fitting but not the right size. I’m letting the Gen run now to see if it will shut off. Then I’m going to pull the injector line, release the pressure and see if it restarts. That should tell me if the fuel is vapor locking, right?
 
I’m stumped here. It ran for thirty minutes. I shut it off and then it wouldn’t restart. The fuel cooler housing wasn’t even warm to the touch. I was finally able to get it to restart after messing around with different things for about five minutes and it’s humming along fine now.

I also had intentions to leave the boat with the injector in hand today so that I could clean it tomorrow. but I didn’t bring the right tools to get it off the generator.

I also also tried to replace the anode. I screwed the old one off but it’s broken off in the exchanger and the new one won’t go back in. Guess I’ll just replace the plug and pretend that never happened for now. If it wasn’t for hurting the resell value I would totally yank this turd out and replace it with a lithium battery bank and inverter.
 
Did you unplug the water flow sensor?
Any code after shut down?
Fuel pressure is critical! Without a pressure reading you won’t know if pump is weak
Get that injector out and clean it!
 
I measured pressure by removing the injector line and measuring at the output of the pump. First measurement before operating was 44psi. After I shut it down and it wouldn’t restart it also measured 44psi, but it was slower to build that pressure.

I will pull the injector off and clean it as the next step, followed by removing the heat exchanger and the fuel cooler to clean those.
 
jmauld said:
I measured pressure by removing the injector line and measuring at the output of the pump. First measurement before operating was 44psi. After I shut it down and it wouldn’t restart it also measured 44psi, but it was slower to build that pressure.

I will pull the injector off and clean it as the next step, followed by removing the heat exchanger and the fuel cooler to clean those.
Click to expand...
You can't clean the injector yourself. There is a special machine that circulates cleaning solution and cycles the injector to remove varnish from the internal workings plus it verifies flow calibration and spray pattern. Send it out to RC Fuel Injection (https://www.rcfuelinjection.com/)or another shop to get done.
 
ttmott said:
You can't clean the injector yourself. There is a special machine that circulates cleaning solution and cycles the injector to remove varnish from the internal workings plus it verifies flow calibration and spray pattern. Send it out to RC Fuel Injection (https://www.rcfuelinjection.com/)or another shop to get done.
Click to expand...
I agree with your statement however, I just went through the procedure myself as I explained in my earlier post and I was successful in cleaning it. its certainly worth a try and it cost nothing.

" FYI..This injector can be cleaned by removing the injector from the mount, hook up a 12 volt battery with a switch and spray with carburetor cleaner and compressed air until you get a good atomization."
 
By cleaning I meant knock out any debris that might be in there which you can do with Lenny’s method. But that service is only $30 and a one day turn around. Might as well do it.
 
jmauld said:
I have been having issues with my Genset this year. It finally got to the point where it just wouldn’t start at all. I opened it up tonight, replaced the plugs, plug wires, fuel filter and seawater impeller, and now it runs great……. For about 15 minutes. At which point it shuts down and returns a UU, UF, 62 or some combination of those codes. Seems similar to the issue described here. I’m not currently at the boat, but I suspect that I need to order a new fuel cooler. This coincides with the cool fuel pumps on my 8.1s failing this year. (Between these pumps and new manifolds, I’m hoping the repair bills will be done for this year).

I have the 7.3ecd low-co model, and I don’t see a parts list specific to this model. Is this part number Gm54991 the correct part number for my Genset?

Should I also order the pump that’s beneath the cooler, or should this pump still be okay?
Click to expand...

installed the new fuel pumps last night. Took the boat out and the generator ran the entire trip with no issues.
 
I've never seen such large amount of really good information (text and images). I had the red LP pump wire corrode off on the pump side of the connector. Have to pull the pick up pump to fix the connector correctly or just splice it. BUT, it looks like it's original so it may be time to change it completely.
 
My 7.3 ECD is stalling out after about 20 minutes of run time and then will start but then stall several times once its warm.
My fuel PSI is right at 45 for the 1st 18 minutes or so so then it spikes to 75 PSI and the engine dies. I have a new fuel injector as well as a newer pump (both High & Low). The boat is from Saltwater so I am guessing that the high pressure pump may be overheating even though the circulation is good causing the fuel to vaporize and increase the pressure, either that or the regulator is funky causing the spike. The genset never gets overheated as it stays right at 190 before the exchanger.
I pulled the injector out and cleaned it just to be sure it had a nice clean pattern and all is good there. Anything else to look at? New plugs and they are gapped correctly. Does Kohler make just a gasket set for this pump module so I can take it apart and put it back together? Any idea of a part # for that?
 
It’s as good of a place as any to start. I wish there were more diagnostic information/tools available to us.

The ignition module(s) are also a common failure point but I would lean towards the fuel pump first.


BTW sometimes I get error messages to show up on the unit‘s control panel that don’t show up on the remote panel.
 
jmauld said:
It’s as good of a place as any to start. I wish there were more diagnostic information/tools available to us.

The ignition module(s) are also a common failure point but I would lean towards the fuel pump first.


BTW sometimes I get error messages to show up on the unit‘s control panel that don’t show up on the remote panel.
Click to expand...
The ignition coils wont make the fuel pressure spike like that. My issue has to be fuel related. I guess I will just pull it apart and see what it looks like, probably at least a $400 tear down cause I dont see any parts that dont include a new high pressure pump with the gaskets
 
Does anyone have the Kohler Exhaust/Catalyst service bulletin SB-692 file?
 
You must log in or register to reply here.

Forum statistics

Threads
113,143
Messages
1,427,143
Members
61,054
Latest member
MrMckinzey
Back
Top