New F70 ticking

[trackhead]

85 hours on new F70.......20 hour service done after break in.

The other day after going along for a few minutes at 5500rpm, throttled down to 1500rpm and heard ticking noise that continued for maybe 2-3 minutes, then resolved. It sounds like a valve ticking noise that I've heard in my four stroke dirt bikes upon initial warm up. It has done this a few times.

Oil level is spot on. Engine runs great, makes no suspicious vibrations or other concerning noises. This noise is an intermittent occurrence, and generally rare.

Thanks for any insight.

[rodbolt17]

my guess would be air in the mechanical pump.
next time it does it pump the primer quicly and see if it goes away.

if air gets in the mechanical diaphragm style pump it will sound like an old chevy with a collapsed lifter.

[trackhead]

my guess would be air in the mechanical pump.
next time it does it pump the primer quicly and see if it goes away.

if air gets in the mechanical diaphragm style pump it will sound like an old chevy with a collapsed lifter.

Sounds likely. There's a backstory that is related, that makes sense when considering your statement.

A few times while running between 5000-5700rpm the motor has stumbled, and I kind of assumed it was fuel starvation because it would immediately go away when I throttle back.

I have recently put on a new, larger diameter fuel line. Haven't been on the water since.

Thanks for the insight.

[trackhead]

Found this video (from post on this forum) with same problem, that's what it sounds like.
https://www.youtube.com/watch?v=Q3tm...e_gdata_player

What diameter fuel line is suggested for this F70? 5/16"?

[rodbolt17]

8mm or 5/16ths.
more than enough.

[trackhead]

New 5/16" line, new bulb primer.........no hiccups or tics in last 6 hours of operation.