Verado Gen5 Stales

[nkarataev2]

Hello everyone,

I'm currently facing a perplexing issue with my 2020 Mercury Verado 350hp (1025h) and would greatly appreciate any insights or similar experiences from this knowledgeable community.

The engine stalls and loses power when operating at high RPMs. This behavior suggests a potential fuel lean condition or a related issue.The fuel water separator and inline filters have been checked and are clean, coils changed. There was a noticeable odd noise from the Fuel Supply Module (FSM) pumps. I'm uncertain if it was from the high-pressure or the lift pump. This noise occurred briefly and then
I've captured this issue on video for better clarity. Please refer to the following links for the videos:

,

.
Has anyone experienced similar issues with their Verado engine, particularly the 350hp model?Could the noise from the FSM pumps be a clue to the underlying problem? Are there any known common issues with this model that might align with these symptoms?
Any advice or shared experiences would be greatly helpful in diagnosing and resolving this issue.

Thank you in advance for your time and input!

 

[alldodge]

Does seem like fuel. I don't know your serial number but it appears the motor might have 3 filters.
Reg Canister type (item 12) and out one (item 3)
https://www.mercruiserparts.com/bam/subassembly/32751/16774/286

Then a inline (item 28)
https://www.mercruiserparts.com/bam/subassembly/32751/16774/180

 

[nkarataev2]

Does seem like fuel. I don't know your serial number but it appears the motor might have 3 filters.
Reg Canister type (item 12) and out one (item 3)
https://www.mercruiserparts.com/bam/subassembly/32751/16774/286

Then a inline (item 28)
https://www.mercruiserparts.com/bam/subassembly/32751/16774/180

Thank you so much for your reply. My serial is 2B755234, I don't have filter item #3 and the external filter #12 and inline filter #28 were changed when I first time got this issue - I thought they had been clogged.

 

[alldodge]

Have you put a fuel pressure gauge on the fuel rail schrader fitting?

I don't know what the reading should be (don't have the manual) but what ever it is it should be steady.

Service manual 8M0133008

 

[nkarataev2]

Have you put a fuel pressure gauge on the fuel rail schrader fitting?

I don't know what the reading should be (don't have the manual) but what ever it is it should be steady.

Service manual 8M0133008

Not yet. I think that's the next step. I should also mention that the issue occurs only when the engine is under load. I tried increasing the RPM in throttle mode but had no success. I'm concerned about the possibility of flooding the engine if I open the cover and connect a pressure gauge, but I'm hoping that simply opening the cover won't cause this issue.

 

[alldodge]

It's fuel supply
Reving in neutral burns very little gas.

Shouldn't flood the motor with removing the cowling but you know your motor better then I. Mine is the V8 verado and the air intakes are high on the back

Start slow and watch to see

 

[QBhoy]

Hi, may have already been covered, but most modern mercs have a fuel strainer screen insert in the fuel rail. Has been known to cause issues by now. some even remove it altogether. Perhaps most likely to cause such a thing would be the usual things like fuel pick up pipe clogging at the tank, non return valves getting clogged etc etc.
Just also came to mind there, that if you have the quick connect fuel fitting to the engine, with the red tab on it like mine. In the last year or so in particular, there has been so many reports over here of these being hugely affected in their ability to create a seal since the introduction of the E10 ethanol content fuel here. The internal seal they have and its deterioration being the cause. Air is introduced at best and at it's worst, not able to pick up or deliver the fuel required.
The FSM and it's internal seals/o rings of course are also well known to be affected in a similar way.

 

[nkarataev2]

Good morning! Thank you for your replies. Finally, the problem was in tank pickup. Hopefully, I have another pickup and I just swapped the plug & siphon valve.

 

[alldodge]

Good deal, thanks for coming back and letting us know

 

[flyingscott]

isn't that motor under warranty