Poppet Valve Repair/Replace

[Wil]

I think the poppet valve on my 150 Merc EFI may be plugged with sand, or simply not functioning the way it should. Is this something I can tackle myself, or should I take it to a dealership? I am reasonably mechanically inclined, but am a little concerned about doing this myself. Your thoughts? My alarm goes off when I get a little over 4000 rpm's I have replaced both thermostats, impeller, flushed the motor, but still having the problem. Below 4000 rpm's motor runs fine. This is simply the last thing I can think off that might be the problem. Never happened before I sucked in some sand from a very shallow sandbar. Is it possible there is sand in the heads, and if so, what does that involve?

[JOE54]

poppett is pretty simple/did you replace all 3 gaskets on pump/sand could be problem may flush it out with hose

[Wil]

All gaskets and new impeller have been installed. Have flushed motor a few times. No sand seems to be coming out now when I flush it. Seems to me like it only leaves the poppet valve to check out. If tat doesn't fix my problem, it will have to go in for service. Thanks for the response.

[JOE54]

see if its stuck open or just sticking

[mdtritn21]

Did you replace the whole water pump kit or just the impeller?

[Wil]

kit

[JOE54]

crank it on hose with thermostats and cover removed for sec or two