*Gen 3 Cool Fuel Module Issue*

No consolation to anyone who has problems but there was no paint flaking on my '07 CFIII. I did crack one of the stupid fittings off at the hose when I was replacing an impeller though and couldnt find a replacement fitting. My boat was used in salt water for two years when new then moved up here into fresh water, I have no idea what the previous owner did for flushing but there was zero corrosion in the housing and no paint flaking.

Since it had low hours I just bought a new housing for 400.00 and it had the newer screw in fittings instead of the whole assembly, still way too much for a breaking a plastic 50 cent fitting IMO. Whoever came up with the impeller/fuel pump setup on these should get kicked in the nuts..
 
As one of the above posts theorizes - I too believe it is an Ethanol based problem - If you have non-ethanol fuel available = no problem
 
In all reality, how many have non eth. available? Of the 2 dealers I spoke with, the reason it wasn't a recall was it is a low percentage problem.
I have not had any issues yet. I also treat every tankful with StaBil, who knows if that helps.
If I do have symptoms of this problem, I'm sure now I can fix this myself cheaply, with the info from the forum and from the dealers. Thank you.
 
Update on my issue.

I discussed this in another thread where I was chasing down an electrical problem that was undoubtably caused by paint clogging the fuel pumps.
You can read about my saga here. ,http://clubsearay.com/showthread.ph...relay-damaged-How-do-I-fix-this-See-Pic/page2

I replaced my Cool Fuel 3 unit, but the replacement part only addresses the poorly designed raw water issue, not the Ethanol/paint issue.

The original design had a water hose connection design I have never seen before. There were plastic plugs that got pressed inside the fuel cool unit that were held in (and removed) by a steel plate with a nut. Tighen the nut and the plugs got pushed in loosen the nut and the plugs come out. When you remove the nut, the steel plate pulls away from the cool unit and trys to back the plastic plugs out, but the plastic plugs break (mine did) and you have to replace the unit. (There is an option to replace just the housing for ~$450 or purchase the entire unit with the pumps ~$1,000 The new unit switched back to a more traditional setup with screw in plugs that the hoses slide over and a hose clamp is used. Once the screw in plastic plugs are installed they stay in the unit and you disconnect the hoses by loosening the hose clamps and sliding them off. Version 3 of this "upgrade" has a blue drain plug that allows you to drain sea water out of the unit when winterizing. So after purchasing 2 of these new and improved units, I come to find out that Mercruiser is still painting the inside and the government is still forcing us to purchase Ethanol. This unit will fail again in the next 5 or 6 years.

There needs to be a class action law suit against Mercruiser for this selling this crap and telling customers that it is safe to use Ethanol, it is not and they know it. I am out $2,000 and lost 1/3 of my summer because of this. What is that worth?

You can see what the inside of my 6 year old Cool Fuel 3 housing looks like. See all the missing paint? It clogged the intake screen on my fuel pump, overloaded the relay which burnt out the relay and the relay socket left me hunting for a fix.

P1050196.jpg


This is what came out.
P1050194.jpg
 
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I've skimmed this thread a couple of times but have a question that may have been addressed it - if I missed it, I apologize...

Has anyone ever pulled a filter (screen or paper) and found paint jammed up in there, or does the paint peeling issues occur downstream of all filters? I'm trying to understand the fuel flow chart. If the problems are downstream, could another filter be placed in that line further down to protect the rails/etc?
 
rondds said:
I've skimmed this thread a couple of times but have a question that may have been addressed it - if I missed it, I apologize...

Has anyone ever pulled a filter (screen or paper) and found paint jammed up in there, or does the paint peeling issues occur downstream of all filters? I'm trying to understand the fuel flow chart. If the problems are downstream, could another filter be placed in that line further down to protect the rails/etc?
Click to expand...
Unfortunately its downstream - the fuel is first drawn through the filters then goes into the pump cavity/pump cover area where the problem is - at the outlet (in the cover) is the first regulator the lines that then leave the housing use a unique o ring fitting and line you would have to have a special high pressure replacement line made with an integrated high pressure replacable filter - this would still not address the regulator on the housing but would protect the rail regulator and injectors...the best solution is cleaning the coating out of the pump cover (solvent, beadblast, etc) and preventing the problem altogether.
 
I figured an additional filter downstream would screw up pressure but didn't realize it wouldn't fully address the problem. Thanks for the explanation!
 
Ron

Theoretically, if you could install an in-line filter between the Cool-Fuel unit and the fuel injector rails on the engine, that would at least prevent the injectors themselves from getting messed up. But the fuel pumps could still get contaminated. And because of the pressure in the fuel lines I think you would have to be very careful what you would install as an in-line filter both from a flow standpoint as well as the pressure concerns.

Dave
 
Both of mine are being replaced (sandy damage) do the new units have the same issues? Should I ask the mechanic to have them blasted?
 
Joe
I think if you get the CF4 replacement you'll be fine...

download
 
I compared part numbers between the latest version cool fuel 3, it's covers pumps etc., and the previous. All parts are the same except for the body, sea water fittings and hoses.
That means to me there is no reason to believe the latest version is not also painted or if over spray all samples may not be affected.
 
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I believe the seawater fittings suffered from corrosion and CF4 solved that problem. The service bulletin points to engine SNs that start with 1A380210 and below (on inboards) as effected. I think someone above commented that said SB did not mention anything about paint chips.
 
The sea water fittings have been modified but the Gen 3 cool fuel unit, to my knowledge, is still painted on the inside. I happened to look at the replacement unit before they installed it on my boat.
 
The newer units have a blue plug for draining the water duirng winterization. They also changed the fittings for the hose to a more traditional design. Brass nipples screwed in with the water hoses attached via hose clamps. However, the inside is still painted. There is a screen on each of the fuel pumps that (in my case) developed a film that made it harder for fuel to pass through. The pumps work harder to generate pressure and then the electrical drain burned out my relay. I changed the entire unit, however the old pumps still work. Mercruiser sells a kit to just change the housing and reuse the pumps. How considerate of them..Don't you think?
 
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Had idle problems and went through IAC replacement and got the dreaded Cool Fuel 3 diagnosis. Estimate provided was $3700 for new module and mechanic also said it include replacing fuel injectors at $250 * 8. Can I just replace the fuel module or do I need to replace the injectors as well ($1700 vs $3700). Boat runs great except at idle and like I mentioned, already replaced IAC and associated filters. How can I be sure the module needs replacing and I am just not getting $crewed for more of my hard earned dollar?
 
As I understand the problem, once the paint starts coming off it clogs up the fuel pumps located inside the unit and some of that paint may also find it's way to the injectors. Why not have the Cool Fuel Unit installed first and see if that solves your idle problem. If it does, then don't worry about the injectors for now..
 
Question...
Nosing around the bilge and noticed that there are no hose clamps on these things, so I took a pic. Is this normal??

arrows pointing to non-clamped hoses...
d905d38f-0f4e-495d-8b6d-b3824a185dba_zpsebfc7fad.jpg
 
rondds said:
Question...
Nosing around the bilge and noticed that there are no hose clamps on these things, so I took a pic. Is this normal??

arrows pointing to non-clamped hoses...
d905d38f-0f4e-495d-8b6d-b3824a185dba_zpsebfc7fad.jpg
Click to expand...

Yes.............that's the way they come. Mine are like that and I verified it with some of the Techs in our service department. They tell me the hoses are on so tight you have to cut them off.

Dave
 
OK. Thanks Dave
 
I am suffering from the same issue. I just purchased a 2006 340DA with 8.1 v-drives, and was having multiple symptoms on the port engine only. It ran rough at idle, and would not go above 3400 rpms. At WOT, the engine would climb to 3400 rpms, and then drop over a period of a minute to 2800 (still at WOT). The IAC valve kept failing, and replacing it only fixed the issue temporarily. A tech finally came and checked the fuel pressure which was spiking. They then found that the fuel regulator was clogged with large chunks of black paint. They called merc, who is sending out new units for both engines free of charge (I still have to pay all labor). I am waiting for the new part to come in now, and am not sure if they are sending just the housing, or the full kit with all hoses, etc... I have heard of people having their engines cut out completely, but not the rpm drop that I am seeing, does anyone know if my rpm symptoms are consistent with the faulty cool fuel module, or could there be another issue I have not yet found?
 
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