Kohler 5ECD Not Running EC62, UU, UF

While waiting for the new parts, and having nothing better to do, I thought I'd investigate as to why the high pressure pump in the module wasn't working.
After carefully cutting off the rolled over end on the bottom of the outer casing and pulling out the innards it looks like this: (the little metallic ring near the end of the casing is the bit that was cut off)
IMG_1940 (1008 x 756).jpg

IMG_1941 (1008 x 756).jpg

From left to right the parts are:
- Plastic top with brushes and outlet nozzle
- Magnet casing
- Magnets
- Armature with 5 little drive prongs that engage in the inner gear
- Pump gear spring steel spacer thingos and wear disc
- Pump gears
- Pump body
The gears and pump internals were totally clogged with what I will call "mud", for want of a better term, no doubt a product of the oxidation of the top of the module.
I cleaned everything and re-assembled it:
IMG_1946 (1008 x 756).jpg

IMG_1947 (1008 x 756).jpg

IMG_1949 (1008 x 756).jpg

IMG_1951 (1008 x 756).jpg

IMG_1952 (1008 x 756).jpg
IMG_1953 (1008 x 756).jpg

Without the rolled over part of the outer casing I had to hold it all together, but when I applied power it ran just fine.
So . . if this pump has been inoperative then presumably the Facet pump alone has been providing fuel to the injector. The flowrate would have been adequate as the Facet has to provide this to supply the high pressure pump under normal conditions, but the pressure would have been considerably less. Maybe just enough to keep the genset chugging along at very low revs, as it was.
A fascinating aspect of the design is that the fuel actually is discharged from the pump body (via the little square hole visible just below the right hand screw in the 3rd and 4th photo) and passes up through the motor before exiting through the nozzle in the blue plastic top. Thus the rotating armature and the carbon brushes are surrounded by the fuel as it passes up though the motor. One way to keep the motor cool, I guess.

Anyway, it was just an academic exercise - the pump is now worthless without the rolled bottom edge of the casing to keep it all together and seal it, but it was fun to see how it all works, and to understand why it wasn't!
 
Maybe I missed something, but how do you know the pump wasn't operating? I thought you just found mud in the fuel injector. How did you clean injector? Also, don't forget to order the barb fittings.

It would be interesting, once everything gets back together and running, to disconnect the high pressure pump and see if it can start or idle with only the low pressure. From the design of the high pressure pump, can a pressurized inlet flow right through the high pressure pump?
 
Pyro (Chris?),

As I mentioned previously, I accidentally pulled the brass discharge nozzle off the top of the pump when I was trying to get it out of the module (I'd pushed it back on in subsequent photos)
Without the nozzle you can see directly down into the pump discharge cavity, and you can also see the commutator, although at the time I thought it was an impeller or similar. When I applied power it moved slightly, then stopped, as though it was binding up somewhere. In fact it was - the pump casing at the bottom was choked with mud, preventing the pump from rotating. Once I'd cleaned and re-assembled it, it spun up freely.
Can you try powering yours to see if you get the same result? It's quite evident when it's running - you can hear/feel it very clearly.

I did find mud in the injector as well, and cleaned it using solvent and also a blast of compressed air into the discharge end (ie back flushing) whilst applying power to open the little piston thingo in it.

The brass discharge nozzle has a non return valve in it - you can see it in one of your photos - looks a bit like a Schraeder valve. It's possible to blow through the pump from the bottom end, but not from the top, thus the Facet pump can move fuel up through the high pressure pump and on to the injector.

When you start the genset there's a few seconds before it cranks when you can hear the Facet pump running, which I believe is priming the line prior to initiating the start sequence. It's the same when you operate the bleed system - I think that's only the facet pump that's running at those times. It certainly was in my case because the high pressure pump was totally clogged and not rotating.

Now I have a better understanding of how things work I'm wondering why the need for the fuel cooler module at all.
I know that fuel vaporisation can be an issue but in this case you're drawing from a 350 litre tank of cool fuel and passing it through a very short injection line into the engine. The HP pump will add some heat, for sure, but the fuel is passing through it so quickly that I can't believe it's a problem. The only time I can see an issue is when the genset is stopped after running for some time and there will be some degree of heat sinking happening in the system.
Even if there is fuel vapourisation in the line because of this, when the Facet starts again it will be drawing in cool fuel and pumping it through in seconds. Maybe the genset will crank a tad more revolutions but it will start once the vapourised fuel/air is flushed through.

With that thought in mind, and not holding my breathe for Walbro to come up with a solution, I'm intending a plumbing modification to overcome the accelerated corrosion we're seeing in the pump module.
Very simple - just run a hose from the outlet of the raw water pump to the inlet of the heat exchanger, bypassing the module entirely. No salt water = no corrosion.

What's the worst that can happen? The engine will not start/stop due to a vapour lock.
In that case I'll reconnect the hoses as designed and start saving to buy another module in a couple of years and/or after another 34 hours of genset operation!!

At about AU$1500 each for the module, it's worth a try!
 
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Did a test on the high pressure pump this morning, just to get a feel for the flowrate, as compare to the Facet, using a cup of clean water.

IMG_1957 (1008 x 756).jpg
IMG_1958 (1008 x 756).jpg


The flow from the HP pump is definitely more than what I saw when bleeding the system, which supports the supposition that it was only the Facet pump that was running at that time.
Also, note the colour of the water - I ran it through 4 or 5 times, returning the same water to the cup.
I didn't dismantle the pump body (couldn't get the two little screws out) so there's clearly still quite a build up of mud in there. It looks very similar to what pyro was seeing in his first post.

Went to the boat this afternoon and replaced the inlet hose from the seacock to the strainer - no dramas all pretty straightforward.
I've also been giving some thought to the heat exchanger. Not all of the salty crap that the fuel module has been producing will have stayed within the module - and guess what's immediately downstream of it !!
So, with that in mind I decided to remove it and check it out as far as possible.
Getting it off was OK other than the rearmost lower bolt - quite difficult to get at.
(Sorry, no photos of the removal - I forgot my phone.)
It was in remarkably good condition, other than the anode connection nozzle - it was full of . . well I guess you'd call it dead anode.
After back flushing with water and gouging the crap out of the anode hole it looked like this.
IMG_1960 (1008 x 756).jpg

IMG_1961 (1008 x 756).jpg

It appears a bit grungy but that's mostly due to a poor paint job by Kohler and a little bit of green surface corrosion - the thing is made of cupronickel alloy.
I tested the thermostat in a bowl of boiling water but no movement at all - bit of a worry as the spec states it should be a 91 deg C unit, so it should be well open at 100 deg C.
I've often thought that the genset was running quite hot - if you lift the hatch after it had been operating for a while you could feel the radiated heat.
So, a new thermostat and 'O' rings and that's hopefully one less thing to worry about.

I also replaced the impeller, and surprise surprise, the one I thought looked new a few months ago was now missing a blade. I wonder where that went - didn't find it in the fuel module or the heat exchanger.
 
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Oh no! You removed the heat exchanger! In fact this is what I did initially as well. I took it out and closed loop flushed it with Barnacle Buster for an hour. It cleaned up a little, but was never the source of the problem. Here's the bad news, you think it was hard to get that last bolt in - you haven't imagined how hard it's going to be getting back in. It took me an hour to get that one bolt in. It was painful. For anyone else, be prepared to get antifreeze all over the place while removing the heat exchanger. I didn't do this, but another tip might be to use a tiny bit of bellows adhesive on that O-Ring. It would not stay in for me when re-installing.

I also tested my thermostat and was unsure how much it was supposed to open, so I replaced it anyways but don't think it was needed.

When I put it back together and ran it, I got a "HE" error (I think, from memory). It was an overheat error. Turns out just pouring antifreeze (AF) back in will cause an air bubble in the block and will not circulate AF. There is a small vent plug at the back right corner on the top of the block/manifold. Open this up, fill until it overflows and then reinstall cap.

I actually have a video of this that might be helpful I was going to post on YouTube.

As for the pump. My pump was definitely working. It would hold 45 psi, sometimes dropping a bit. I think the fuel was just so contaminated the fuel injector clogged and couldn't run. Your brownish water is a perfect example of that.

I noticed a small drip of water around my hose between fuel pump and heat exchanger. That 100 mm :) hose is pretty well worn and may not be compressing very well to the barbs. I could probably crank on the hose clamp more, but probably better off with a new hose. In the mean time, I wonder if there is a small course filter that we could find that is worth adding after the impellor to catch the inevitable impellor bits.
 
Yep, I was thinking that getting that bolt back in was going to be a bitch - thanks for confirming it!

I've tracked down another local supplier for Kohler parts who seems a bit more switched on that the previous guy I dealt with. I ordered a new thermostat and 'O' rings, for the eye watering price all up of AUS$120.40! Did I mention that this stuff is expensive in Australia?
I noticed there were 2 part numbers for the thermostat, one is for a 160 deg F unit and the other is for the 195 deg F (91deg C) but based on the genset serial number I apparently need the higher rated one.

No work on the genset for the past couple of days - the weather has been too good to pass up on the chance to get across to Rotto for an overnighter.
 
Excellent write up and pics guys!! The Kohler Generator could almost be made into a mini-series for NBC. "The life and times of a Kohler mechanic". Anyways, i experienced what you were experiencing with my Kohler 5ECD in the past. My Genny mechanic said he was not re-installing a new Pencil Zinc because they deteriorate and cause most of the clogging. Just thought I'd pass that along for consideration.
 
Mark,
Interesting comment re the anode - mine had completely disappeared and I think has been in there since 2007, so probably not doing anything for the past 9 - 10 years!
Nonetheless the heat exchanger is in excellent condition even without it - so the anode doesn't appear to have any purpose.

On that subject, I received the following response from Walbro after sending them a few photos and a link to this thread - will be interesting to see if I get any follow up.

Thank you for reaching out to Walbro with your concern with the material used in the fuel cooler/pump module found on the Kohler generator in your Sea Ray 355 Sundancer. I have passed your email onto the Walbro people working with Kohler on this generator application to investigate the issue of corrosion. I want you to know that both parts are made from the same raw material (UNS A03560 – T51 Aluminum) and same hardcoat. Below are the specifications pulled from the drawings of both parts.

Got my order from ASAP in Pennsylvania a few days ago and before re-assembling the system I took the top off the module for a quick look inside.
The first surprise was how little effort was required to take out the 6 screws – they were not much more than finger tight. Could this be part of the reason for the leakage/corrosion?
The quality of the components is actually very good, including the castings, but I did notice some corrosion on the outer surface of the pump casing. Not a big deal I guess as this doesn’t come into contact with the fuel, but not what I would expect from a new part.

So here it is all ready to go back on the genset:
IMG_2039 (1008 x 756).jpg


What’s missing in the photo is the inlet hose from the raw water pump to the module. I intend by-passing the module as explained in a previous post, (note the plug in the outlet) but I will install the inlet hose now and just cable tie it out of the way, as it’s very difficult to get at with the genset in the boat. That way, if the by-pass idea doesn’t work it’ll be relatively easy to revert to the standard plumbing.

So, back to the boat in the morning and hopefully have an operating genset again.
 
I still want to know what the change was between GM39595 and the superseded part GM54991. I need to double check but I don't see any numbers stamped on the original painted housing.

Can other people with 5ECD please post a picture of the top of their fuel module along with age and hours, and water type (salt/fresh/brackish).

What's the temp where you are? Very curious if you will run into vapor lock. I am contemplating doing the same. Let me know how it works on a hot day.
 
I spent an entertaining 4 hours in the engine compartment of my boat this morning re-installing the fuel injection system for the genset.

The part I was dreading, getting the bolts in for the Facet pump bracket, wasn't actually all that difficult, given that I couldn't see them.

The PITA part was that pesky bolt at the bottom of the rear flange on the heat exchanger. After struggling with it for
about 10 seconds (I have a very short tolerance threshold) this was the answer:

IMG_2044 (1008 x 756).jpg

The exhaust was easy to remove and gave good access to the bastard bolt. (Ironically it's not visible in this photo!)

As I was bleeding the fuel line in preparation for the first start the Facet stopped and the error code EC58 came up.
A quick check online showed this to be Engine Coolant Temperature Sensor Input High. I had omitted connecting the plug to the sensor in the bottom of the coolant tank.

So, second try and success - it started and ran fine. After shutting it down and feeling very pleased with myself I noticed a drip of coolant from the heat exchanger front flange. AAArg!
Nothing for it but to remove the HE again and check it out.
The 'O ' ring was OK so I suspect that the thermostat wan't seated correctly in it's groove.
It's difficult to hold the thermostat in place while you fit the HE to the flanges - in hindsight I should have glued it in with some gasket sealant. I used grease to keep the 'O' rings in place.
Got it all back together and this time no leaks.

The only action remaining is to replace the exhaust gasket - I've re-installed it with the old one and although it's pretty crappy it doesn't appear to be leaking, but I will replace it anyway.

My plan to bypass the fuel module didn't eventuate.
I had a length of hose, clamps, etc. all ready to go but when I tried to fit it from the raw water pump around the front corner of the control panel it was obvious that it wasn't a good idea. It was forced to take a sharp bend around the corner of the panel by the proximity of the port engine muffler - I could see it either developing a kink or maybe rubbing through. Also it passed across the front of the panel at about the level of the "Run" switch. Not the end of the world I know, but not a good look either.

I haven't entirely given up on the idea - I'll get a couple of elbows and try to make the hose run a bit neater and without the possibility of getting any kinks in it. For the moment, though, I'm just happy to have the genset working again.

Interestingly enough, it didn't give any LOC code although the raw water system was empty for the first start.
I had a look over the side and it was pumping through plenty of water so all seems to be OK.

If I get a response from Walbro I'll post it here, but for now that's me done until I revisit the raw water bypass idea.
Thanks to pyro for being the first - it made it much easier knowing what to expect.
 
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A follow up to my genset saga - specifically related to removing and replacing the exhaust system.

If you're planning on removing what Kohler call the "Catalyst", basically a stainless steel silencer-type thing that I suspect is a sort of catalytic converter, you'll need a couple of 'O 'rings and probably a length of 50mm (2") exhaust hose.

What I thought would be a straightforward job started off badly when I tried to pull the rubber hose off the catalyst:
IMG_2068 (1008 x 756).jpg

It had hardened over time and become very brittle - it literally fell to pieces as I tried to twist it off .

When I had previously removed the catalyst to get at one of the HE bolt's I didn't look too closely at the flange so after failing to find a part number for a gasket I bought a piece of gasket material intending to make my own.

Big mistake - the "gasket" is actually a pair of "O 'rings that looked like this:
IMG_2069 (1008 x 756).jpg

Referring to the parts manual again I see that they are listed, but simply as 'O 'rings - I had seen them previously but ignored them as I was looking for something called a gasket.
I sourced an equivalent locally - they're made from Viton which is a heat resistant rubber.
Also worth noting are the two water passages that are blocked with salt. (I had cleaned out the top one before taking the photo) Can't be helping much with raw water flow through the system.

So, the genset is running and all issues have been attended to, other than the raw water bypass.
Will get onto that when I get the parts I'm waiting on.

As a matter of interest I took a few temperature readings using an infra red thermometer:
Fuel Module - ambient temperature before starting the genset - 19 deg C
Fuel Module - after running for about 5 minutes - 28 deg C
Fuel line from module to injector - 40 deg C
Coolant tank - 105 deg C

I'll check them again after the by pass.
 
Wanted to post back final results: It runs perfectly in the boat. Ran it with AC load. Turned on and off a few times. Worked perfectly.

Wish you posted the exhaust pipe gasket before I reinstalled my generator! I would have also checked that while it was sitting in the garage. To hard to get out now.

Talking to my friend with a Volvo about this, he mentioned about a aftermarket Volvo fuel cooler for $200!
https://www.amazon.com/Volvo-Electric-Assembly-21608511-21545138/dp/B076Q9RG1R
This seems somewhat similar to the Kohler setup.

He thinks the regulator is external, so not sure what type of pressure this makes. If I had found this earlier I would have explored if it was feasible to use. Surprised that aftermarket makes fuel coolers for Volvo, but nothing for Mercruisers. Just posting if someone in the future wants to explore that further.

Curious to see other people's pics of their fuel modules to see what condition they are in.
 
Wanted to post back final results: It runs perfectly in the boat. Ran it with AC load. Turned on and off a few times. Worked perfectly.

Wish you posted the exhaust pipe gasket before I reinstalled my generator! I would have also checked that while it was sitting in the garage. To hard to get out now.

Talking to my friend with a Volvo about this, he mentioned about a aftermarket Volvo fuel cooler for $200!
https://www.amazon.com/Volvo-Electric-Assembly-21608511-21545138/dp/B076Q9RG1R
This seems somewhat similar to the Kohler setup.

He thinks the regulator is external, so not sure what type of pressure this makes. If I had found this earlier I would have explored if it was feasible to use. Surprised that aftermarket makes fuel coolers for Volvo, but nothing for Mercruisers. Just posting if someone in the future wants to explore that further.

Curious to see other people's pics of their fuel modules to see what condition they are in.
That link you posted doesn't appear to be a fuel cooler. It's a filter combined with a low and a high pressure pump. There doesn't appear to be a water inlet/outlet.
 
I think the hose is water in and the smaller brass fitting on the top is water out (or maybe vice versa)
Fuel inlet is at the top (side) of the filter and outlet is the larger brass fitting on the top (on the centreline of the pump)
 
I purchased a boat with known bad generator Kohler 5ECD generator. These are the fuel injected generators and many people seem to have similar issues to what I am facing. Hoping to share some of what I learned.

Problem description is the generator would not start intermittently. Some days it would start but would die shortly after. It would throw errors EC62, UU and UF. This year after dewinterization the engine barely runs.

We determined the issue is likely fuel related. The fuel injector was replaced 2 years ago on this unit and has less than 4 hours of runtime since that service. We removed injector, tested, and discovered the injector valve was sticking. Sometimes tapping on it would release it, other times you had to wait. We are going to send it off to get cleaned. Kohler part number for this GM62619 and is somewhere around $130. The injector is actually a Siemens Deka injector with part number 39-032. Also labeled on the unit is 8032F06572 and 07/315 15. There is no information on the internet for this injector. I called a local injector cleaning company, they barely wanted to talk. I emailed another place online, no response. I emailed InjectorRx and to my surprise the owner called me and went out of his way to look up the specs for this injector. I am sending the injector to InjectorRx. I think I have found an equivalent Bosch injector but waiting for confirmation from the guy at InjectorRX for confirmation. I can't say enough about how helpful this guy was - send your injectors to InjectorRx!

Plugging up an injector so quickly points to something else wrong. Generator is out of the boat and operating from an external fuel tank. We would prime the fuel system and noticed the first bit of return fuel from the schrader valve near fuel injector was initially a noticably darker color. After a few seconds it would clear up as it fresh gas from the tank made it through the entire system. This has been repeatable for 3 times letting it sit for more than 3 days. The discoloration is coming from either the high pressure water cooled pump, pick up pump or the fuel line.
View attachment 68188

The fuel on the right is the first fuel out of the pump after being in there for about 4 days. The fuel on the left is the new gas from the external tank and collected AFTER the stuff on the right. It does not seperate after leaving it overnight. I'm not sure why its discolored, but I suspect its clogging the injector, and I suspect I'm not the only one with this issue.

Next we are going to measure the fuel pressure from the high pressure fuel pump - although no one knows what it's supposed to be. Then attempt to check if fuel discoloration is from high pressure or low pressure pump. We may try a close loop flush of Seafoam or other cleaner to see if the internals can be cleaned up. Or we may attempt to open the top up to inspect insides. Not sure if this is servicable so expecting to replace at that point. I suspect the high pressure fuel pump is a standard off the shelf fuel pump with a custom Kohler assembly to water cool the pump. This thing is very expensive ~$550, but no alternatives found so far.

If I replace the high pressure pump I will probably replace the low pressure pump to guarantee an entire new fuel system. I was able to find a cheaper source for the low pressure pickup pump. The Kohler part number is 278490 and runs about $110. It is a Facet Pump part number 40178 that creates 2-3.5 psi. You can find this for about $60, only difference is you will have to splice the connector onto the new Facet Pump. The part number is actually stamped on the bottom as documented here:
https://www.pegasusautoracing.com/document.asp?DocID=TECH00023
Cross reference: http://www.facet-purolator.com/wp-content/uploads/pdfs/2018 Industrial catalog.pdf

Will post updates.
Hi I ordered the GM62619 Fuel Injector and it only has 2 prongs on the electrical connection and it doesn't have the screw that goes into the housing. It also doesn't say MotoTron SENSTMAP001A01 on it like mine does. Any ideas where to get this part, I cant find it online anywhere.

Chris

index.php
 
That's the MAP sensor (manifold air pressure). Are you trying to replace fuel injector or MAP sensor?
 
Oh :/ well that makes sense why they don't look the same. I think I need to change out the fuel injector if I knew where it was. I don't see it called out in any of the service views, do you have a pic of where it is installed?
 
For some reason the fuel injection parts are not called out in any of the service manuals or parts manuals. I have no idea why.

The fuel injector is on the other side of the white hose. You can see the connector at the very top of your picture in the background. You can trace the hard fuel line and follow it towards the small manifold with the shrader valve with cap. The black thing with the connector and two wires is the fuel injector.

Remember you will need to bleed the fuel line using that shrader valve after replacing it. Hold the select (dot) button down while switching switch to run. Take a valve with hose and bleed fuel out for a few seconds or until no bubbles. I was never able to get a good enough connection to the valve to get no bubbles, but you can tell when most of the air is out.

Why are you replacing it?
 
Oh, its the thing with the 2 white wires coming out of it in this pic?

When I try and start the generator it cranks but immediately faults our to a UU code.

Initially I was getting an LOC code, i replaced the old water hoses and cleaned out the strainer and replaced the water pump impeller and this code went away.

I also replaced the fuel/water seperator and inline fuel filter, and spark plugs.

I disconnected some of the terminals on the SCR and re-connected them and it turned on (a lucky start), so I replaced the SCR module thinking that was the trick but no luck.

The negative battery terminal was all rusted so I decided to loosen the bolts and wire brush the connections but of course one of the terminals just broke off from being so corroded so just ordered a new of those. Maybe that will fix it, doubt it.

I've been reading on clubsearay, some people changed their fuel injector and it fixed the UU problem.

I really have no idea..but welcome any advice. (I hate this generator)

Chris

yfCmfRQsRZ2cnW480Hw0Dw.jpg
 

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