Engine Overheating due to Sea Grass

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Bolt79
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Joined: September 12th, 2017, 8:15 am

Engine Overheating due to Sea Grass

Post by Bolt79 »

Hi everyone,

I’m new to the forum and thanks for the add. Hoping someone here can give some insight on a problem I’ve had the last few times I’ve been out with my boat. I fish out of Horseshoe Beach and lately I’ve been having a problem with floating seagrass clogging the water intakes on my motor which is causing it to overheat. My boat is a 2014 Xpress H20B with a Yamaha F115. I’ve got a manual jack plate and the pad to prop is currently set to 4.5 inches. It doesn’t seem to matter whether I’ve got the motor trimmed high or low, it still clogs up at various times (I’m guessing depending on the amount of floating seagrass that’s in the water).

I’m supposing that this is a problem that’s unique to our area due to the floating grass on the flats. Just wondering if anyone else has experienced this, and if so, could you share some insight on how to resolve the issue. Thanks.
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big bend gyrene
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Re: Engine Overheating due to Sea Grass

Post by big bend gyrene »

Be surprised if there's anyone on the board who's fished our area long without having the exact same problem. Few things I can tell you for whatever they're worth...

1) I do seem to have a bit less clogging if I run my engine lower in the water column (assuming adequate depth) and with it tilted a bit back versus completely forward
2) May sound obvious, but I do my best to dodge visible grass mats as running through them is an invitation for clogging
3) At least with my E-tec 90 I can almost always HEAR the moment the intakes get clogged as the audible pitch of the engine running goes up. If I ignore it, I'm going to hear the overheat alarm in short order. So what do I do? One of two things... first is to make sharp zig-zagging steering movements with the hope that turning the engine side-to-side will catch the grass and sweep it off. It works quite often. When zig-zagging doesn't work, I simply stop the boat, shift into reverse, and rev up a time or two... this pulls the grass off the intakes every time.
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FUTCHCAIRO
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Re: Engine Overheating due to Sea Grass

Post by FUTCHCAIRO »

WHAT BIG BEND SAID, I VERY SELDOM GET MY INTAKE CLOG, I RUN MY PROP PRETTY DEEP AND VERY SELDOM GO OVER ABOUT 30 MPH, IF IT CLOGS, I WILL HEAR IN INCREASED RPM AND STOP AND PUT IN REVERSE AND REV THE ENGINE SEVREAL TIMES AND MOST TIMES THIS WILL CLEAR THE GRASS OFF THE INTAKE.
PA
SEMPER FI
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Rogan
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Re: Engine Overheating due to Sea Grass

Post by Rogan »

I had a Yamaha F115 and had the very same problem. Mechanic told me the poppet valve was sticking shut and not allowing water to flow through the engine properly. I thought my problem was grass initially. It wasn't a very expensive fix and I never had another problem after that.
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MudDucker
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Re: Engine Overheating due to Sea Grass

Post by MudDucker »

Getting grass on your kicker is almost inevitable in the big bend area. As others have said, listen for the change in the tone of your engine and stop soon after you hear that change. Gun the motor in reverse once or twice to clear the prop and then proceed.
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DixieReb
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Re: Engine Overheating due to Sea Grass

Post by DixieReb »

Happens to me all the time, reversing the engine always fixes it for a little while. Lots of floating grass this time of year, and the storms probably pulled a lot more loose. I like what BBG said about avoiding the grass mats, that does help some.
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Bolt79
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Re: Engine Overheating due to Sea Grass

Post by Bolt79 »

Thanks for the responses. Good to hear that it’s a common problem on the flats, especially right now when the grass is really bad. Usually, what’s been working for me is to just stop the boat, shutdown the engine, and let the backwash roll up and hit the back of the boat. Then I can fire it back up and everything’s back to normal. I tried running with the motor trimmed all the way down, but that didn’t help either.

Hey Rogan, not sure what a poppet valve is...could you please elaborate? I bought my boat used back in May and the motor has around 200 hours on it, so I’m gonna change out the water pump impeller to see if it helps. Is the poppet valve something I could also replace when I do the impeller?
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Russ@R&R
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Re: Engine Overheating due to Sea Grass

Post by Russ@R&R »

Bolt 79, The poppet valve is not located at the water pump. Look online for "how to replace poppet valve on Yamaha F115". Not hard at all. (Just be careful to NOT drop any of the screws down the midsection)
Rogan
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Re: Engine Overheating due to Sea Grass

Post by Rogan »

Bolt79 wrote:Thanks for the responses. Good to hear that it’s a common problem on the flats, especially right now when the grass is really bad. Usually, what’s been working for me is to just stop the boat, shutdown the engine, and let the backwash roll up and hit the back of the boat. Then I can fire it back up and everything’s back to normal. I tried running with the motor trimmed all the way down, but that didn’t help either.

Hey Rogan, not sure what a poppet valve is...could you please elaborate? I bought my boat used back in May and the motor has around 200 hours on it, so I’m gonna change out the water pump impeller to see if it helps. Is the poppet valve something I could also replace when I do the impeller?
Here is a thread that offers better information than I can provide.
https://www.thehulltruth.com/boating-fo ... es-do.html
"No, I dont remember where I last had it, if I knew I'd go get it" ...
flatsbroke22
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Re: Engine Overheating due to Sea Grass

Post by flatsbroke22 »

All great info here. Only thing I will add is you may want to add a water pressure gauge to your helm. I have one and when the grass is a problem I keep one eye on it at all times. At an instant you'll see the pressure drop and know when you stop and clear it before it over heats.
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JIm Smith
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Re: Engine Overheating due to Sea Grass

Post by JIm Smith »

pressure gauge is a great asset I have had one the last three boats and if I ever get another boat to replace the one I have it will have one ,
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Price3275
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Re: Engine Overheating due to Sea Grass

Post by Price3275 »

JIm Smith wrote:pressure gauge is a great asset I have had one the last three boats and if I ever get another boat to replace the one I have it will have one ,
I add a water pressure gauge to every boat I have if it doesn't already have one, and look at it very frequently, as well as listening for change in motor noise like they said above. Noise changes and a pressure gauge will let you know you have a cooling system problem BEFORE your heat alarm goes off.
Bolt79
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Re: Engine Overheating due to Sea Grass

Post by Bolt79 »

Russ@R&R wrote:Bolt 79, The poppet valve is not located at the water pump. Look online for "how to replace poppet valve on Yamaha F115". Not hard at all. (Just be careful to NOT drop any of the screws down the midsection)
Thanks, Russ. I’ll check it out.
Bolt79
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Joined: September 12th, 2017, 8:15 am

Re: Engine Overheating due to Sea Grass

Post by Bolt79 »

Rogan wrote:
Bolt79 wrote:Thanks for the responses. Good to hear that it’s a common problem on the flats, especially right now when the grass is really bad. Usually, what’s been working for me is to just stop the boat, shutdown the engine, and let the backwash roll up and hit the back of the boat. Then I can fire it back up and everything’s back to normal. I tried running with the motor trimmed all the way down, but that didn’t help either.

Hey Rogan, not sure what a poppet valve is...could you please elaborate? I bought my boat used back in May and the motor has around 200 hours on it, so I’m gonna change out the water pump impeller to see if it helps. Is the poppet valve something I could also replace when I do the impeller?
Here is a thread that offers better information than I can provide.
https://www.thehulltruth.com/boating-fo ... es-do.html
Thanks, Rogan.
Bolt79
Posts: 12
Joined: September 12th, 2017, 8:15 am

Re: Engine Overheating due to Sea Grass

Post by Bolt79 »

Thinking I see a water pressure gauge in my boat’s future. How difficult is the install?
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