*Gen 3 Cool Fuel Module Issue*

I had other stuff done at the same time, I think 2-300
 
Does anyone have this bulletin? Are they replacing for free now? I recently was advised I have peeling paint.
I was told it's not a recall but a goodwill gesture, I was expecting to pay for it but the shop called and said Merc would cover the parts. Module.. hoses and fuel injectors.
 
Looks like Merc is going to provide parts. Work has to be done at a dealer, not a certified mechanic. For those of you who have done this, how many labor hours to do the whole thing? Injectors, cool fuel, rail etc?
 
Looks like Merc is going to provide parts. Work has to be done at a dealer, not a certified mechanic. For those of you who have done this, how many labor hours to do the whole thing? Injectors, cool fuel, rail etc?
I paid $600 per engine, not sure what they charge an hour most likely 4/5 hours per engine
 
And that is for everything? I called a dealer in CA and they said approx. 3500. I thought that was crazy!

$3,500 is a total rip-off. I pulled the unit the first time, along with the fuel rails and changed the injectors and even I could do it in a fraction of that time.
 
Working on my Kohler Generator today and noticed how familiar the design of their fuel cooler is to the Dreaded Cool Fuel III.

The right is the top cap of the Kohler fuel module.
Same harness. Same plug. Same method of sealing the wires through the cap.

I had just finally rebuilt both my Mercruiser fuel coolers last week.
New Bottom Housings, New top Cap.
Loaded them with the original pumps, filter module and pressure regulator.
This is the newer bottom section design with the threaded holes for the water hoses and the removable drain plug.

PLEASE NOTE:
The new bottom blocks are NOT tapped for the 6 screws that hold down the cap.

The top cap is NOT tapped for the screws that hold down the pressure regulator.

The 3 holes for the fuel filter ARE tapped.

I first thought this was a mistake. But now I think this may solve the mystery why those 6 screws have such a high torque value and why they almost always break when you try and remove them.

I have seen this once before on a cheap leaf blower.
When I disassembled the old fuel coolers i was very careful and did get a few of the screws out. But then I couldn't match the screw size and pitch with anything.

So: I got a bottoming tap and tapped them and bought new screws off Amazon.
Remember Somewhere before I looked up and found a huge price for the "special" mercruiser part number screws.

I really wonder if this has been uncovered before.
I wonder if there are any factory trained tech's on this board that can confirm my Theory!
Hope So!






Fuel Coolers.jpg
 
I have a cool fuel 4 that was already replaced once sometime in the last 12 years. It is leaking fuel out the top of the silver pressure regulator. It looks like the top cap is corroded around the pressure regulator.

Can I get the top cap off without breaking the screws? Any tips? What to do if they snap off?
 
You can get it off - if I remember correctly, the two fuel pumps are housed beneath that - I've had it off many times (years ago,which is why I can't remember!). Get it off without breaking screws?? That's another story.

Does the hosing look corroded around any of the screws? If yes, the corroded ones are going to be the the difficult ones. I suppose if you break the screw you can get a machinist to drill it out and re-tap, or tap it a bit larger. But if there's corrosion outside there is probably corrosion inside as well. It's like an exhaust manifold - if water is getting OUT it's probably getting into the exhaust passages. And if that's true of your CF4 you do NOT want water getting in the fuel.

Try it - you've got nothing to lose - worst case, you need to buy a whole new unit. Best case you're OK.

And be sure to send a thank-you note to Mercruiser for yet another wonderfully stupid design!
 
The housing so far looks like it's in good shape. I would expect the corrosion to be where the raw water circulates. However this is where I believe it is only fuel. I am hoping it's just the o-ring around the pressure regulator but I can see some corrosion on the cover around the pressure regulator. Hard to see in this pic, but you can see approximate location.

upload_2020-5-24_23-30-23.png


I'll try to remove pressure regulator off first then work my way down to the cover.
 
The housing so far looks like it's in good shape. I would expect the corrosion to be where the raw water circulates. However this is where I believe it is only fuel. I am hoping it's just the o-ring around the pressure regulator but I can see some corrosion on the cover around the pressure regulator. Hard to see in this pic, but you can see approximate location.

View attachment 85419

I'll try to remove pressure regulator off first then work my way down to the cover.
You probably know this already, but relieve the fuel rail pressure before removing the regulator. I found out the fun way on my first CF3 replacement.

Also, I found the reason my regulator began to leak was because of the paint blockage against its intake screen. The fuel pump was pumping/pressurizing but enough fuel couldn’t find a way through the paint to exit via the regulator so it egressed the next path of least resistance—the regulator o-ring.

Depending on how long ago your module was updated, you may still have a painted cover that’s now flaking. That was my situation on the starboard side. Module cap (no longer painted), regulator, o-ring, quad seal o-ring kit is #8m0130861. Removal of the module is necessary for access. Hope you don’t need this info...
 
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