Replacing Cool Fuel III

I remember there being a screw but no real trick. I think it's got a detente in there that may be catching. Make sure you pull STRAIGHT out.

Yes, water will flow through - The chambers where the filter is and the fuel pump is (and the gasoline) is jacketed with seawater - that is what cools the fuel.
 
Just changed mine today. To remove the fuel line, loosen all the cf bracket bolts so it can move around. Then wiggle the fuel line while shifting the module around to get it to unbind.
 
Ok great thanks for your help.
 
you could:
move the pumps to a more convenient location and use a trans cooler to cool the fuel .trans coolers have threaded fittings
 
Hey guys, I had the same water leakage problem as many of you had, with the gen 3 module. I successfully reamed and taped my older case to accept threaded fittings. The key here is your case cannot be too corroded. You have to go to a 1/2" fitting, because the existing hole is bigger than 3/8". I used a 23/32" straight machine reamer(just under 3/4"). Now I used a drill press and put the case in a vice. You need to make sure to secure the case CAREFULLY in the vice. Not too much pressure. You are not taking much material. Just ream it very slowly. There isnt much ligament to play with on the outboard side. And on the upper hole, you have to be careful not to go in to far because there is a cast in threaded screw hole (for your fuel pump cover. You could potentially break it off. Then CAREFULLY tap the hole with a 1/2"-14 NPT Tapered pipe tap. I taped it by hand just so I had more control, with a 12" adjustable. Make sure to use oil or better yet taping gel. The key here is make sure your taping nice and straight. Again not much ligament to play with. Then clean the holes, and the whole inner cavity while you're at it. Then install your 1/2"-14 ×1/2 " fitting/nipple combo. Or 1/2" reducer and a 3/8"× 1/2" nipple. Either way will work. Use perfect seal or equivalent to seal them in. I also used my existing hoses. I just took out the old plastic inserts. I had to crush them and take them out in pieces, but it wasn't a problem. Just buy a couple of s.steel hose clamps. I hope this helps. Thanks
 
The fitting issue isn't the CF3's biggest problem. Even more of a problem is the paper thin wall in some areas separating the fuel and the water jacket.

When I had mine on the bench doing the fittings, I also sealed the water side with a POR tank sealer product
 
Yeah, that was a good call, sealing the waterjacket. Another of the many great engineering designs by Mercruiser. Not! Oh, and lets not forget about the paint flaking issue. I also like the fact that they offer a "FIX", but not a recall, and charge the customer $100. more. Awesome!
 
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question for this great thread

I've read several of these and I'm pulling mine over the winter to check them out.
Several have mentioned breaking cover bolts.
Is there locktight on the bolts from the factory?
On other applications it is suggested to heat up the area to soften the locktight.
I don't want to create a problem by breaking a bolt just to do the inspection...
 
Galvanic corrosion...stainless screw in an aluminum housing. Heat would help if it's gas free.
 
yup! I don't want to be featured on Mythbusters!
Somewhere earlier in this thread there was discussion on a check valve ball with a spring.
I couldn't see the picture very well, but it looked like it was removed from the outside.
if that was removed, would it drain that side of the module?

I have been poking around the internet for alternative aftermarket solutions if I find these to have issues.
Marine Power has an interesting option called a g-force module
Volvo/Penta has their version and I found an inexpensive copy of it for under $200 on ebay for both pumps and a $10 spin on filter.

Also my Mercruiser Parts manual shows the gen2 version was used on the alpha version of my engine. It has a return line from the fuel rail to a spin on filter. I wonder if that's a simple plumbing retrofit or if it involves the alpha ecu.

This thread is great, but i wonder if there are any other options since it was active?
 
Can anyone tell me if i have the infamous cool fuel gen 3 modules? The catalog lists the part number as 864650A05 which only describes it as ‘cool fuel module”. However, what’s actually installed on my boat is 864650A01 (pictured). I can’t find hardly any info online about this part number. Im really not sure what I have here.

8123AEA1-0BA8-4C5E-A128-FF8F95119812.jpeg
 
Can anyone tell me if i have the infamous cool fuel gen 3 modules? The catalog lists the part number as 864650A05 which only describes it as ‘cool fuel module”. However, what’s actually installed on my boat is 864650A01 (pictured). I can’t find hardly any info online about this part number. Im really not sure what I have here.

View attachment 64827
From the partial picture it looks like the one on my boat. I dont know how the part numbers in the catalog work, but maybe yours is the first version and the -05 is the latest update
 
Thanks. Any idea if it’s one of the early units with the paint issue? I suppose I need to grab the serial. The hoses are connected with hose clamps on these units. If they are of the defective variety, Mercury will replace these correct? I haven’t had any issues ..so far.
 
I had a 2006 with the paint issue. Easiest check would be to take the FPR off and see if there are any chips on it. Simple take off.
 
Thanks. Any idea if it’s one of the early units with the paint issue? I suppose I need to grab the serial. The hoses are connected with hose clamps on these units. If they are of the defective variety, Mercury will replace these correct? I haven’t had any issues ..so far.
The fact that it has hose clamps leads me to believe that it has already been replaced.
 

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