Sheared off water intake female

[fairdeal]

in your position, I would defer digging down to install the Yamaha part,
and stop by the hardware store for a male hose quick connect stop fitting
to plug the hose off




meanwhile, nothing about that hose would keep the engine from starting.

Nor would the previous "overheat alarm".

I can't imagine any relationship to your current no-start problem.

[Angler Management]

Thanks, fairdeal. That's the plan to carry a spare or two onboard of the hose fitting you show.

In contact with my mechanic, who also supports what you said, the engine should start. Possibly the stick I saw was only a piece of a larger log I hit and there's a gear tooth missing, or maybe the overheat was worse than I imagine and there's a head gasket issue.

Regardless, if she doesn't start tonight, she's off to the shop. Where, in addition to getting the engine to start, maybe they can take the throttle assembly apart and re-attach.

Thanks for your input!
Randy

[zenoahphobic]

in your position, I would defer digging down to install the Yamaha part,
and stop by the hardware store for a male hose quick connect stop fitting
to plug the hose off




meanwhile, nothing about that hose would keep the engine from starting.

Nor would the previous "overheat alarm".

I can't imagine any relationship to your current no-start problem.

That fitting should be the type where it is shut when not connected to a garden hose that has a male end. I'd imagine it is simpler than having to unscrew and then screw in a male adaptor, particularly with cold figures!
Bad luck this was the sticking out adaptor model motor that got "hit", most I've seen are protected somewhat in the cowling.

[Angler Management]

Sometime after my 07 engines were made, Yamaha added a one way valve to the apparatus so it wouldn't suck air. My friend's latest 300HP Yammy has no hose at all, just a connector sticking out from under the cowling.

I spent $3.99 at Ace yesterday and threw this into my junk box on the boat just in case lightning strikes twice....

[fairdeal]

I spent $3.99 at Ace yesterday and threw this into my junk box on the boat just in case lightning strikes twice....

ahh! 3/4" hose to male NPT
nice
I would not expect to find that local to me - you've got a great hardware store

[FabricGATOR]

anything really

The broken flush hose part, as already stated, is just a threaded plug. I see that we all undertstand. That being said, anything to stop the loss of waterpump generated cooling water coming out of that hose should work (if at all really necessary) You could fold the hose over and wrap tape around it, screw in your ACE hardware plug, remove the fitting from the hose end and secure a stick in the hose, screw in the Yamaha mounted plug part and just let it dangle...

And, really, the waterpump usually makes more cooling water than is required and a part of that water is designed to be wasted overboard via the water jacket pressure regulator poppet valve. (on most models, as stated by RodBolt)

Your no start discrepancy is most likely not related to that broken fitting.

Do please, and I ask this of everyone, please report back what you find to fix it. Too many times people ask for help, get the answers, and then fail to report back what worked and what did not work. This leaves much of the archive devoid of solutions but full of suggestions. Some good and other not so much...

Cheers!

[Angler Management]

Totally will check back in, you bet.

I'm stumped, it just seems to be too much of a coincidence that this part was the only thing damaged when the alarm went off.

[Angler Management]

Update:

I made sure the batteries were fully charged last night. Despite being on shore power in my driveway, I still don't completely trust my 4 battery setup, I did have one go bad last spring... different story. Anyway, I ran Starboard first to make sure everything was at max charge, then swapped earmuffs to Port. After two tries she started. Wasn't smooth like Port, though. As it warmed up I thought I heard one cylinder missing. Ran at idle for 10 min and the missing went away. Upped the RPM to 2000 out of gear and ran another 5 min, no problems, but still didn't sound completely smooth like Port. But definitely strong...

THEN, I backed her down to idle and put it in FWD and immediately got an overheat alarm. Quickly shut it down. Restarted after a few minutes, ran fine at idle for 5 min, ran fine at 2000 for a minute, ran it in reverse for a minute, then FWD and I got another overheat alarm.

SO... something is wrong! I'm happy she's started, I'm trailering her to my mechanic this evening and he said he'd look at her briefly tomorrow morning. Will certainly pull the plugs, check the thermostat, and hopefully this isn't a broken tooth off the drive train or head gasket issue.

Strange.

Thanks for your help guys. I'll report back early next week.

[TownsendsFJR1300]

THEN, I backed her down to idle and put it in FWD and immediately got an overheat alarm. Quickly shut it down. Restarted after a few minutes, ran fine at idle for 5 min, ran fine at 2000 for a minute, ran it in reverse for a minute, then FWD and I got another overheat alarm.
.

Did you run / test the other engine as well EXACTLY the same (@2K RPM's, same time, etc) and no alarms?

The larger motors, on muffs, it's not unusual to get an overheat alarm, especially at 2K,

If any of those batteries are questionable, get them load tested... Low voltages/amps/bad batteries can ALSO cause running issues...

[Angler Management]

I tested them pretty similarly...

I understand that muffs may not be ideal for heat, that gives me hope. But the alarms didn't go off at 2k, they only went off when I put the beast in gear from idle.

We shall see... Thanks!

[99yam40]

did the alarm go away when put back into neutral?
strange how putting in gear would cause it to alarm.

[FabricGATOR]

What are the seas like up there in Seattle? I've not been boating up there.
Not weather and waves but salinity and marine grown potential. Are you trailered primarily? Do you flush regularly.

The reason I ask is I had overheat fault occasionally when I purchased from PO.
A friend and I believe he takes care of his equipment. I believe I found it to be caused by calcium and salt build up in the water jackets.

I dropped the LU's to service the waterpumps and while I was there, I made a closed loop system to circulate RidLyme through the engine using an old fresh water wash down pump that the pressure switch had failed and a reservoir so I could recirculate the fluid. RidLyme claims that there product will not harm the metal of the engine and that it will dissolve the buildup like a cough lozenge.

Worked for me..

[DennisG01]

It's possible that the impeller is worn or the flow from the muff to the impeller is somehow impeded (or the flow from impeller to engine). Going from 2K down to idle causes the impeller to slow down (pumping less water). And the initial "clunk" into gear may cause the drivetrain to slow down a bit more. Possibly just enough to decrease the amount of water pumping through the system to a point where you may have had not enough water or an air bubble to cause a quick spike in temps. If the hose is on the low side of GPM that might help to explain it, too.

Possibly a flaky sensor/switch, too. You could try swapping port for stbd.

Can you back the boat into the water and retry? A hose doesn't supply as much water as actually being in the water.

[TownsendsFJR1300]

I strongly suspect, with the engine (still on the trailer), backed into the water, you would NOT have the alarms...

The initial issue(broke hose holder itself) wouldn't cause overheat issues, but that flushing line OPEN, COULD...

Yes, now it's closed, but 2 k on muffs, is a bit high, ESPECIALLY on such a large engine. Very possible you were right on the edge of setting the alarm(on the muffs). RPMs lowered to shift, WP slows as well, less water, aluminum block sets off the alarms(block is STILL HOT)..

IMO, I'd back it up to the ramp and re-test in the water...

[Angler Management]

More info:
Got my pro involved this morning, found a disconnected breather tube on port, filling the cowling with exhaust. Could explain the difference in sound vs. stbd.

Also she doesn't appear to be pumping as much water as Starboard. But of course it's tough to tell on the muffs. Will replace impeller on both engines while we are at it.

She checks out on electricity fine. New plugs might as well since we are here.

Time for new thermostats too, so will do that.

Lower units are brand new with 20 hours on them (another story for another time) so I wouldn't expect lower unit corrosion to be in play.

Will also check gear lube for metal and quality just to make sure.

No thermostats on hand. Will do all this extra work this upcoming week, then do a test run next weekend.

So I think we found enough here to be comfortable with the overheat alarm and rough running. Fingers crossed for the run next weekend.

Thanks for all the input! I love to learn through troubleshooting.