2006 - 340 Sundancer with the 8.1L...
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07-28-2019 07:40 AM
2006 - 340 Sundancer with the 8.1L Mercs. I'm having a fuel starvation problem. Ran it for about an hour and when I was pulling into the dock, the starboard motor ran rough and then just shut off. No faults on the smartcraft. I've had my mechanic down twice to help me troubleshoot. If we fill the coolfuel module with fuel, it fires and runs until is burns through the fuel in the cup. We've now replaced the Low pressure pump in the coolfuel, enabled the by-pass in the electronic fuel shut off, (confirmed there's actually fuel in the tank!), and think we've narrowed it down to a bad pickup in the fuel tank.
Does anyone have any experience with a pickup going bad? What's involved with replacing it?
Thanks in advance!
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07-28-2019 08:35 AM
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07-28-2019 09:28 AM
Current thinking is there's a crack in the pickup that's letting air in the system. We're going to throw 15 gallons in the tank to see if that "fixes" it.. or at least helps diagnose the problem. Idea being that the crack was low enough down that it was fine what I was running and had fuel, then I just hit the point where air was getting in the way of suction.
Last big trip I made I got pretty beat up.coming down the coast with weather... if the pickup was weak, that definitely could have over stressed it.
Problem with the pick-up, we can't figure out how to access and remove it without drilling a hole in the deck. Otherwise, we'd just pull it and check. Was curious if anyone on here had a trick to doing it in a 340 without drilling.
Open to other ideas!! Thanks!!
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07-28-2019 10:26 AM
Were they defeated or opened for the test?
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07-28-2019 10:27 AM
https://live.staticflickr.com/4745/40465168062_560799e07e_b.jpg
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07-28-2019 10:49 AM
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07-28-2019 10:53 AM
The valves Sea Ray used on my boat have a twist knob providing an on position and and electrically controlled position.
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08-04-2019 12:07 AM
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08-04-2019 07:19 AM
My mechanic ended up taking the cool fuel module off the motor so he could test it on a bench. Ran it off a remote tank like you suggested and it seemed to be working fine. We're trying to isolate if it's a problem on the motor vs. the tank-side. Current theory is going back to the Parker Hannifin value.
We think it failed and closed which starved the engine of fuel. When we tried to use the bypass, we didn't think to prime the 8 feet of fuel line from the valve to the cool fuel module. Mechanic had Mercury on the phone to help troubleshoot and they were saying the pump wouldn't be able to clear that much line of air. On a shorter hose (2 feet) on the bench, it would be ok. That's why we're thinking it worked on the bench but not in the boat.
Another data point - he has a Power Probe where you can power basically anything off 12v. When we tried to power the valve directly, it would trip the circuit of the tool.. that's what's leading us back to the valve.
Interesting side note - I couldn't find the Parker Hannifin valves anywhere online accept on ebay. I was a little leery of ordering this part through an ebay seller but since my local Sea Ray dealer never got back to me, figured why not give is a shot. I was surprised that the return shipping label listed Brunswick Boat Group out of TN. 1/2 wonder if Sea Ray is selling these online through Ebay or their drop shipping direct for a reseller. Either way, think it's a legit OEM part. I might just order an extra one since they seem hard to come by.
We're going to try to prime the line and swap the valve Mon/Tues this week. I'll keep the group updated so it's on the forum and hopefully helps someone out that runs into this in the future.
Thanks BigTuna and Wingless for batting around ideas with me!
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08-04-2019 07:20 AM
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08-04-2019 07:40 AM
You have 2 fuel pumps a low pressure and a high pressure. In fact you probably have a good 4-6 ft of fuel line between the tank and the engine. Had to do most of the work myself after begging and chasing mechanics to do their job, and coming up with a new excuse every time as to why they have to go back and forth. As far as parts goes, I learned that whenever I buy a part online I have to order an extra one due to high rate of failure. I found that local searay dealers don’t care about carrying parts or providing services unless your boat is less then 5 years old as very clearly a local told me last year.
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08-04-2019 10:09 AM
The cool fuel modules I replaced when I bought the boat about 5 years ago. It sat for a while (window was selling after her husband died and took her a while to get to that point of selling it) and the ethanol broke down the paint and sent it down the rail. had to replace all the fuel injectors as well.
I'm kind of wondering if I should be looking to replace the fuel lines and how much ethanol breaks them down. Part of me wonders if the lines are just compressing when under pressure and choking off the fuel flow. Boat is a 2006. Have you replaced the fuel lines or does anyone on here know what the service life is?
Will post when I learn more
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08-04-2019 12:09 PM
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08-04-2019 07:34 PM
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08-04-2019 07:52 PM
High pressure is good. If you get fuel into the CFM, it pumps into the rail and the boat runs. We're going to mess with it more tomorrow... I'll keep you posted.
Thanks for all the ideas and discussion. Very helpful!
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09-16-2019 12:24 PM
Ended up buying a full CFM assembly vs. swapping more parts in the CFM and that solved my problem. Ironically, the CFM was the first hunch but my mechanic (and buddy) was trying to eliminate all other variables before throwing a $1300 part at the problem without knowing for 100% certainty that was the issue.
Current theory is that the electronic fuel value went bad and failed closed; when the pump ran dry, it cause some type of unknown issue and the CFM to fail. Replacing the fuel valve and CFM got me back up and running.
Adding to the ToDo list for the winter is to replace all the fuel lines (figure it's cheap insurance and I won't ever have to do it again in my ownership of the boat.
As for Stabil - I use it EVERY fill up on all my boats. I had the paint issue with the CFMs 5 years ago when I bought the boat. Replaced the CFM and all the injectors at the time.
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10-01-2019 01:09 PM
I tried looking at the wiring diagrams in the manual but didn't have much luck finding it.
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10-01-2019 03:18 PM
An extended documentation package I have shows a two wire harness feeding that shutoff valve, driven by a splice for the wire feeding the engine electrical fuel pump, with Gray being signal and Black being ground.
That documentation shows the linked Packard Electric 280 Series connectors between the existing fuel pump feed, as-shown starting on page 23 of 111 in the link.
https://www.reynoldsonline.com/ASSETS/DOCUMENTS/ITEMS/EN/12033769_Spec.pdf
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10-01-2019 03:29 PM
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10-01-2019 03:33 PM
If so, then can a DC voltage meter be connected to the hull fuel shutoff valve electrical connections to determine if those valve are also receiving power, to command that they open?
Please provide the results of that measurement.
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10-01-2019 03:35 PM
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10-01-2019 03:56 PM
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10-01-2019 07:32 PM
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10-04-2019 07:50 AM
Cut out and pulled that piece of the harness. Going to rebuild the connections and rewire and see where that lands us.
@vinster - I replaced both the CFMs and all the injectors when I bought the boat 5 years ago. Ever since then, I use fuel stabilizer every fill. That said, we swapped the CFM on the "bad" motor with a new one... i'm not convinced the old one is bad and it maybe have been my electrical issue... but not going backwards at this point. (any thoughts on how to test a CFM on the bench to see if it's good?... I'm going to hang onto the old one anyway)
Making progress. Commentary welcome and I'll make sure I post updates
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10-04-2019 08:34 AM
Yes, corrosion is bad and can cause problems.
It may be that the measured voltage between 0 and 13 VDC might be normal, caused by the measurement tool and not indicative of a problem.
It is "easy" to be fooled by a digital voltage meter, making extra steps required to understand reality.
On my boat, the fuel pump is energized, then stops. That would be observed as 13VDC, then 0VDC.
The Mercruiser engine uses that Packard Electric 280 Series connector, from the engine harness to the fuel pump. Sea Ray created a splice harness, w/ pigtails to go between those Mercruiser fuel pump connectors and w/ a long fly lead to power this hull fuel shutoff valve.
It should be possible to unplug this Sea Ray part, plug the Mercruiser connectors back together and turn the fuel valve to always on, to restore normal operation.
With that Sea Ray harness removed, then it should be possible to perform bench measurements to determine if good or bad.
If that harness is bad, then purchasing a replacement may cost more, but might work out better because of the special crimp tools required for the connector contacts.
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10-04-2019 10:50 AM
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10-04-2019 11:02 AM
@Vinster - I think you're right... why waste time. I did swap the low pressure pump in this journey. I'll probably pull that since is was basically never used and junk the rest.
Definitely looking forward to closing out this thread and getting back on the water! killed 1/2 of my summer!
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