f30 stumble

[Navigator]

My 2012 F30 hp starts and idles fine. When I try to accelerate the engine stumbles and wont throttle up. No water in tank or filter. I suspect fuel pump failure. Is rebuilding the pump simple like the old 2 strokes?
Any other ideas what may cause this problem?

Thanks

[pstephens46]

How many hours? How long has it been stored? Marine gas or ethanol used?
Check fuel pressure when it stumbles...probably low. Fuel filters? There are several.
Including the VST. Some of the filters can be cleaned, some have to be replaced.

[TownsendsFJR1300]

Has the engine sat with un-stabilized, ethanol fuel for over a month?

IF SO, it sounds like your CARBS need cleaning, especially the main jets.
The jets have extremely small orifices which clog up.

Here's the parts fisch for your carbs, enlarge the page, carb #1 show's
the main and idle jets, etc:
2006 and Later F30TLR Yamaha Outboard CARBURETOR Diagram and Parts

[pstephens46]

I believe this motor is FI. Same premise though. Something, somewhere is obstructed or dying...

[boscoe99]

Here in the good ole USA, the last F30TLR with a carburetor was made in the 2005 ~ 2006 time frame.

First EFI F30LA/LEHA had a production date of January 2013.

Hard to speculate for sure what the OP has. Time for the motor to go to a shop IMO.

[99yam40]

does that mean there were no F30s made between 2006 and 2013?

[boscoe99]

does that mean there were no F30s made between 2006 and 2013?

Can't tell if any were made or not but when it comes to what was offered here in the US, this is what I am seeing at Yamaha US's website.

Now that I think about it some, I think the F30 EFI was offered by Yamaha Canada a year or so before Yamaha US offered it here in the states. Navigator may be a Canuck eh!

[pstephens46]

Inspector Boscoe scores! He left a visitor message on my profile. He lives on Vancouver Island.