Carver Owners Forum

That is the thing as boats get older and pass thru different owners and mechanics.....things get changed, upgraded from the stock way they came.

Good luck with your launch and new tranny....

Just closing the loop on my port motor stumble.
We launched and did a full throttle test run to test the trans. The port motor stumbled at anything over 2000.
Tech hooked up a flow meter and we observed a distinct whine for two seconds, and a corresponding dip in fuel pressure, then good for 4 seconds, then down for two.
I have two pumps on each motor. Of course it was the $300 one. Tech ordered what he thought was right, but my pump has a return circuit also, so it has two intakes, one output.
Found the right one and now the problem is solved. Took until July 11 this year to get our first day out on our own boat, but it was worth the efforts.

chpsk8 - did you ever notice any popping or snapping sounds in the port engine? Sounds like a snap head flopping in the wind and hitting fiberglass. er

thank you very much for posting the solution to your issue. i wish more people would do that. do you mind to post the part number of the fuel pump you installed so anybody else with same crusader engines could make note for future reference?

Dredging this one up again for an update.
In 2021 I had a loose water separator on the port motor that caused the motor to completely die. It would suck air and die off. I could almost predict when it would happen. 45 minutes of run time, then it would die, but could be started immediately. Found the water separator was loose. Tightened it up, and no problem.

Fast forward to this spring. I launched and could barely get the port motor to start. This is the same motor that I replaced the primary fuel pump in 2020 and had the loose water separator in 2021. So frustration is high at this point. We fiddled around a little and it started and was able to run at 1800rpm in the slip without problems. So the next day we took off up the Mississippi. About an hour into the trip we come up on the stern of a barge. The river is narrow so we have to wait for the right spot to pass. We had been motoring around at 1700 rpm and about 9 mph. I throttled up to pass and sure enough... the port motor dies off like it's fuel starved again. I tried one more time about a mile up the river and it died again. Not wanting to get in front of a barge and have a problem we just sat behind it for the next 8 miles... at 4.5mph. Safety first! Kids not happy.

After many hours of staring at the fuel system and going over what I've changed and not changed I decided to research the little "lift" pump that takes fuel from the tank and pushes it to the main fuel pump on the front of the motor. That little pump is a Walbro FRB-20. Turns out that pump has a filter inside of it that needs to be cleaned! I took it apart last night and it was pretty much 100% clogged. So that pump was starving the primary pump which in turn caused the primary pump to fail. The bad news is the primary pump is now whining again so I'm sure I've damaged it in some way and shortened it's life.

Now I need to figure out how to clean the filter on the starboard motor. I don't fit in the front space in front of the motor so I need to find a small person that can help.

I'll leave some links here that might help someone in the future.

The primary pump I used in the original problem that started this thread.
https://marineenginedepot.com/fuel-pump-high-pressure-gm-pump-with-return?gclid=EAIaIQobChMI1az52rWi6gIVDNvACh0vLgIwEAQYAiABEgJ0TPD_BwE

An option that another user here found that needs a little modification to the harness to work. (move the plug to the other side of the pump) much much cheaper.
https://theropshop.com/shop/products/electric-fuel-pump-marine-power-438603-ra080023-556017

The Walbro FRB-20 pump that is being used as a lift pump in advance of the primary pump.
https://walbrofuelpumps.com/frb-20.html

The wow moment when I cleaned the filter in the Walbro FRB-20

Great update. On any "new to you" boat one of the priorities should be locating ALL the fuel filters. In the older carb boats, there was frequently one on the input fitting on the carb but wasn't visible because it was inside the fitting. Lots of folks had to find it when they started having problems and had already changed out all the other filters.

Ya the whining is a sign that she was starved of fuel while operating. Since the fuel is what lubricates it, it doesn't take long before you reduce it's longevity by running on reduced input volume. This is also common when guys replace fuel filters on applications with electric pumps without filling them up first. Eventually the pump starts whining and then it's just a matter of time before it fails, which will be at the worse time like when you're trying to pass a barge Replace it soon before it leaves you stranded.

There should never be small in size/fine filtration on the suction side of a pump as cavitation occurs and will cause issues as shown here. A pump will easily handle small particles. Filtration on the output (engine) is a much better option as the filters have much more surface area and get changed on a regular basis. All the gunk shown on the filter in the picture would just tickle a main filter and not cause any issues.

Thanks for the update/solution.

I have a new fuel pump in transit to me now. I bought the $80 one since it does cross reference with the original. I did try replacing this pump in 2020 but it would always leak even though it's all hard pipe for the connections. I ended up calling a mechanic to finish it up for me. He took an hour to do it even though I had all the hoses off and the area prepped for him. (actual hour, not billable hour).

#Viper... Any tips on making those hard pipe connections seal? I'm fairly mechanically inclined. It was bit of a disappointment I couldn't get it to seal myself. Seemed like no matter what angle I put things on, or how tight I tightened it, I would always get a drip out of at least one connection.

#midnightsun... I agree with your point on the filter so early in the process. It's a 70 micron filter. I asked the previous owner who had the boat for 11 years and he said he had never changed it. The original owner wasn't that great with maintenance so we're thinking it's never been cracked open before.

chpsk8 wrote:Qr Bbpost ...
I asked the previous owner who had the boat for 11 years and he said he had never changed it. The original owner wasn't that great with maintenance so we're thinking it's never been cracked open before.

Glad you clarified that part. I was going to ask if this was just one year of accumulation or from a much longer time.