Where is the Fuel Pump/Cooler assembly on a Mercruiser 4.3L MPI?

[groovy_moon]

Fuel pump crapped out over the weekend. It doesn't sound normal at all. It makes this kind of grinding noise.. The engine wont stay running.
1) Where do I start looking for it
2) Has anyone just changed the pump? Horrible job?
3) Has anyone used pumps from "fuelpumpfactory DOT com" They aint cheap but they claim to be better and more durable than OEM.

Here's a vid of what it does.
View attachment 20210606_133604[1].mp4

 

[groovy_moon]

PS: I have the real factory service manual so I know the procedure.. It's just vague on the location (well and the procedure a little bit as well)

 

[dubs283]

cool fuel III is located along the stringer between the engine mount and block

cool fuel iv is located front stbd side of engine about halfway between top and bottom of engine

 

[groovy_moon]

Thanks.. I have a 2010 engine. Cool Fuel IV?
In behind the PS pump?

 

[dubs283]

I have a 2010 engine. Cool Fuel IV?

dunno, can't see it

IV has the "basket" style filter housing held in place by three bolts, located fwd stbd side of engine

 

[groovy_moon]

dunno, can't see it

IV has the "basket" style filter housing held in place by three bolts, located fwd stbd side of engine

"dunno, can't see it"... LOL that's funny right there.. Come on down.. beer's on me..

I have the correct Mercruiser Factory Service manual for my engine and engine S#. It doesn't show anything that looks like CF 3. I think CF3 was on V8's. The manual shows a kind of enclosure that opens up and has the fuel cool tube, pressure regulator and a separate pump. The pump looks like a cylinder about 4-6" longs and about 1.5" diameter..

 

[groovy_moon]

"dunno, can't see it"... LOL that's funny right there.. Come on down.. beer's on me..

I have the correct Mercruiser Factory Service manual for my engine and engine S#. It doesn't show anything that looks like CF 3. I think CF3 was on V8's. The manual shows a kind of enclosure that opens up and has the fuel cool tube, pressure regulator and a separate pump. The pump looks like a cylinder about 4-6" longs and about 1.5" diameter..

dunno, can't see it

IV has the "basket" style filter housing held in place by three bolts, located fwd stbd side of engine

But seriously... I have the spin on fuel filter over on the starboard side of the engine sort of in the lower left corner as you face aft at the front of the engine. And yes I put a new fuel filter on before I winterized here last year.

 

[groovy_moon]

I think I have this one

 

[dubs283]

I think I have this one

that's the cool fuel iii, located along the stringer between the motor mount and block. most likely port side

 

[LWD]

I have a 2001 4.3 MPI, mine is port side. In the picture, if you follow the water hose with the blue check valve on it, it should take you to it. I had to install the check valve to prevent vapor locking with my fuel pump.

 

[groovy_moon]

A few weeks ago I ran the boat to burn up some of last years fuel. I then went to a different from my normal station because they were selling rec gas for $3.45/gal.. Which is really cheap.

Yeah I am pretty sure I had vapor lock and the pump was ok. I started the boat up last night in the driveway on the muffs.. Pump sounded a little raspy for a second or two and then normal and the engine started right up. I let it run for about 30 minutes.. I took it up to 3K a few times. I then shut it down and hooked up a fuel pressure gauge. When keyed to "ON" the pressure went to just about 40 psi. Spec is 43. So $44 dollar gauge accuracy may not be that great.. I then started it and the gauge was just oscillating 38-40 psi at idle...

Where did you get that valve? Which direction is the flow... Up or down? How does this keep you from getting vapor lock. I have a few extra of those blue wing nut plugs.. Love the fitting...

Also.. I think I am just going to leave my blowers on when running... and open the "hood" for a little bit when stopped...

Yeah.. I found the pump/cooler module.. That is one job I DO NOT want to do in my driveway... Looks to be behind the motor mount down by the oil pan... YUCH... something as important as the fuel pump should be WAY more accessible.

 

[LWD]

There's a water drain port for the fuel pump water cooling system, I have to crawl in the back port side, by my trim motor. You have to be half contortionist to drain it, I turn on my right side and pull a couple wires out of the way with my right hand, then work my left hand in upside down to get a grip on the blue plastic drain plug. Getting it back on is fun too...

Attached is the service bulletin on the vapor locking, it also specifies the check flow valve to use. I think the flow is raw water first, then to the thermostat. For some reason this service bulletin is hard to find.

 

[LWD]

That check valve (P/N 21-862271A 1) is about $130, at it's cheapest, it's pricey for what it is, but worth it to help avoid vapor locking while on the water. But after being stranded a few times, and having to wait 1 1/2 hours each time for it to restart, it was worth it for me.

During winterizing, it does add another drain point.

 

[groovy_moon]

That check valve (P/N 21-862271A 1) is about $130, at it's cheapest, it's pricey for what it is, but worth it to help avoid vapor locking while on the water. But after being stranded a few times, and having to wait 1 1/2 hours each time for it to restart, it was worth it for me.

During winterizing, it does add another drain point.

Thanks!!! I see on eBay for $119