*Gen 3 Cool Fuel Module Issue*

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Does anyone have a reliable contact at Mercrury or Someone that could confirm this?
Almost $350 for 12 screws i need for the two units. Likely to break upon removal
 
Holy crap! That's insane. Find a similar fastener at McMaster carr and buy a really good tap. Curious what you paid for this housing? I replaced both my CF3s with CF4s a couple of years ago. Each unit was around $950.
 
Next later model. Has a blue drain plug, screw in seawater fittings and supposedly no issues with paint peeling off the interior and clogging injectors.

Mine came with screw holes that were tapped.

OK, I just looked up what you bought. You got JUST the housing, 8M0047216, which costs less than $500. You COULD have bought 864650A13, which is the entire drop-in module. Runs about $1200. Apparently you have to now buy screws for $350, which gets you to around $8xx. Still a savings of $400.

You cannot buy a CF3 anymore. Unless you find someone with new-old stock. And You wouldn't want to buy a CF3 b/c of it's flaws. Anything you buy now is going to be CF4.

THIS is a CF3 module...
https://www.mercruiserparts.com/bam/subassembly/31679/12827/50

THIS is a CF4 module. Note #2 (plastic NPT water fittings) and #3 (blue wing-nut drain plug), both not featured on the older CF3.
https://www.mercruiserparts.com/bam/subassembly/31680/13883/45
 
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Ok, thanks.
I didnt know that Mercruiser changed the name.

Yes, I bought the new version of the housings. I also got the newer covers that are anodized instead of paint. Seven Seas bought the Kent Island location of Clarks Landing. I asked them about the housings and they had two on the shelf. I think maybe they are downsizing their inventory and they offered me a way better deal than you mentioned.
My engines have about 400 hrs and were running great except for being clogged up with silt. I pulled them this spring and am doing a light rebuild and going over all the acessories. Being a curious person and reading all the hype about the gen 3 fuel coolers i had to check them out. Everything on the inside was very clean. The covers had some gunk ,but not nearly as bad as others.

The water side of the housings were corroded and the nipples were shot as expected. I had replaced one set sever years ago.
On the screws, the math was based on 6 per housing. There are actually 8 including the two that hold the pressure regulator.

I use Mcmaster Carr a lot and will likely check. I have picked up some test screws at Ace. The original screws seem excessivly long and i think they bottom out in the housing. They dont look like most self tapping screws.
 
I replaced both cool fuel units in the last two years, one in the spring of 2017 and the other in the spring of 2018. The originals had the peeling paint issue.
This spring while still on the hard the blue plastic plug on the starboard engine module cracked off. I thought it might have been bumped while cleaning the bilge. It was a bear to remove the remaining threaded portion as it was falling apart and fused to the aluminium housing. I had to use a tap to allow installing a new blue plug.
Last week after a trip down the coast I noticed my bilge pump coming on. It turns out the port fuel module plug was cracked and nobody ever touched it. Same crumbling mess.
This is a safety issue ! I never remove these plugs because I winterize with pink antifreeze.
Mercury does not have their act together on this. I am fed up.
 
Fred, I had a blue wing nut break off too, and noticed it the same way you did (bilge pump was coming on). At first I thought I had inadvertantly cracked it somehow, but the more I thought about it the more I was certain I never bumped it. It was the stbd engine.

After the same grief you went through to carefully drill out the old one, I noticed the new one, when fully tightened, was resting on the fuel line. Thinking that maybe, over time, the vibration would cause a break, I backed it out and ground off part of the wing that touched with a Dremel. Now there is no contact.

I too have never removed these plugs, and both were relatively new (less than 5 seasons). The port one has not broken off nor have I replaced it preventatively. Maybe I should(?)
 
Why not just replace them with brass? Most people I know never use the to winterize any way. My cf3's are still the originals but when I replace them thats what I'm thinking of doing.
 
I will not replace the blue plug with another plastic one. There is a definite problem with them.
I will use the stainless steel ones that are available and use plenty of tef-gel to prevent corrosion with the aluminum module. I have even considered using 5200 on the threads.
The new Mercury blue plugs are not made of the same material as the old ones. It appears they are soluble in propylene glycol. Not good.
 
Hmmm. I am very concerned about galvanic corrosion on these $1000 aluminum pieces of junk. Maybe make replacing the blue ones annually should become part of the regimen? They're cheap enough.
 
Hmmm. I am very concerned about galvanic corrosion on these $1000 aluminum pieces of junk. Maybe make replacing the blue ones annually should become part of the regimen? They're cheap enough.
If you try that approach, leave the plugs out after you pink the system. My starboard side only saw one winter storage and it was destroyed.
I'm going with metal and working on it this afternoon.
 
There are wingnuts in other spots on these engines as well, I think (?)
 
I recently discovered that the paint on my Cool Fuel 3 module is peeling and as a result my entire fuel system is full of paint particles. Unfortunately I wasn't even aware of the existence of this problem until now, and I have since read every thread on every forum I could find to gather as much information as possible.

I am currently in the process of repairing all the damage. I sent my injectors to SouthBay Injectors in NY for cleaning, and I thoroughly cleaned the fuel line and the fuel rail. I am not 100% sure what to do with the fuel pump cover however. I am aware that there is a new anodized cap, but I am not sure if I should buy it, or simply strip all the paint off of mine and use it as is. Do you think the bare aluminum would corrode and cause more issues?

I am also curious if there are any better alternatives to this Cool Fuel module? Have any of you ditched this POS and replaced it with something better?
 
I don't think ditching it is an option. You're likely going to have to replace it with the Cool Fuel 4 module, which seems to have solved the flakey paint problem. If your CF is original (now 14 seasons old) it might be a good idea to replace it anyway. Not cheap but...
 
I recently discovered that the paint on my Cool Fuel 3 module is peeling and as a result my entire fuel system is full of paint particles. Unfortunately I wasn't even aware of the existence of this problem until now, and I have since read every thread on every forum I could find to gather as much information as possible.

I am currently in the process of repairing all the damage. I sent my injectors to SouthBay Injectors in NY for cleaning, and I thoroughly cleaned the fuel line and the fuel rail. I am not 100% sure what to do with the fuel pump cover however. I am aware that there is a new anodized cap, but I am not sure if I should buy it, or simply strip all the paint off of mine and use it as is. Do you think the bare aluminum would corrode and cause more issues?

I am also curious if there are any better alternatives to this Cool Fuel module? Have any of you ditched this POS and replaced it with something better?
I stripped mine and had no more problems for several years then sold the boat. It won't corrode any faster than the inside of an aluminum gas tank
 
I stripped mine and had no more problems for several years then sold the boat. It won't corrode any faster than the inside of an aluminum gas tank

That’s great to hear, thank you. Aircraft striper took the paint right off with a little bit of elbow grease. I was second guessing myself because of the oxidation, but you make a good point with the aluminum gas tank - I hadn’t thought of that.
 
There's a service bulletin out, and Mercury will replace the module and injectors if you have an authorized service center do the work.
 
I've heard reference to this service bulletin but haven't seen it. Not sure if it still applies.
 
I just had my fuel injectors and cool fuel module replaced, I only paid the labor
 

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