Optimax 115hp poppet valve?

[zack123]

Hi,
Had an intermittent 'beep' coming on when at idle last weekend, did some research and it's leading me to think it's the thermostat, will check that out first. Also, saw a lot of mention of the poppet valve. I've been going through my service manual and I cannot see anywhere at all that mentions where this valve is on my engine? Can anyone confirm if the 2007 115hp does indeed have a poppet valve? and if it does, where abouts can I find it?

Engine serial number: 1B519455

Thanks

[JOE54]

sure does upper back of block small cover has 4 bolts/ ser# shows it has one

[zack123]

yep, it's under the same cover as where the tstat is. Just for anyone that comes across this issue.

basically a couple of weeks ago, I beached the boat and upon leaving I think a lot of sand got sucked up. When I increased throttle not long after, guardian kicked in and lowered the revs right down, but then I had no further issues that day so I thought the the sand must have caused water blockage but then got pushed out.

but then last week, at idle, I can see the engine temp on the smart craft sitting at 73 and would not increase, even after running at idle for 5 mins, then a single intermittent beep would come on, but no beeps when running at higher revs. So putting 2 and 2 together + a bit of internet sleuthing = bad thermostat.

which has lead me to putting this thread up, with a possible poppet valve issue as well. Opened it up, and it was full of sand, and the tstat was stuck also. Dug out all of the sand, replaced the thermostat. Started it up, and a lot more water coming out of the pissa and engine temp rising as expected, and no more warning beep.

[SilverFox579]

Don't forget all that sand went through your water pump before finding its way to your thermostat and poppet. Now would be a good time to replace it.