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Ants in my lower unit

J

John W

New member
I have a 2003 Honda 225 on my bay boat. I store the boat in a side yard under a cover. I had not run the boat in 3 weeks, so I ran it this morning on a hose to warm up the motor & move some oil around. When running there are various small holes built into the lower unit where water escapes by design...these holes are about the diameter of a pencil, and there are three or four on each side of the lower unit. So water is coming out of those holes, out of the prop, and out of the pee hole in the upper part of the motor as normal. Suddenly, ants start running out of the holes on the port side of the lower unit, some of them carrying eggs! I have an ant nest in my lower unit!

There were dozens (not hundreds) of ants coming out. They looked like carpenter ants, not a dirt building ant like fire ants. The motor ran fine at idle on a hose. I tried to wash them out as best I could, but I have no confidence I got them, or any nest debris, out of the lower unit.

I figured I would take the boat out tomorrow to run it and wash away any ants...but now I'm wondering if ants or nest debris could get sucked into the powerhead water passages somehow and clog them. Is this a possibility?
 
Now that's a new one on me !!!!

I guess it depends on how big the ant nest is.

I would take it out for a spin and run with cover off. Use an IR heat gun to check manifolds. They should heat up to 160 F on each side.

The most likely area to get clogged is the water pump indicator hose (i.e. pee stream.) Carry aboard a 3 ft piece of string cleaner or 300 or 400 lb monofiliment to open it back up if clogged. If it continues to clog, you may need to remove the nipple on the water jacket and clean out behind it. Just keep an eye on the pee stream and monitor the heat on your manifolds.

If it does overheat. Pull the boat, remove the prop, and put the lower end in a tub of water, making sure the water level is well above the water pump, remove one t-stat at a time and start the engine, and run very briefly. That should blow out any debris. Be prepared to get wet.

As I thought through this, one other thing occurred to me. On the mount case, you have two water pressure relief valves. They COULD be vulnerable to a clog, and they are a bugger to get to. If you are overheating, and all else fails to clear it, you will likely need to get to those, disassemble, and clean them out. See items 9 at:

https://www.boats.net/catalog/honda/outboard-by-hp-serial-range/225hp/bf225a6-la-2006/mount-case
 
Sorry to jump in and side track but do you know what these relief valves do? i could never work it out, perhaps something to do with the flush port (which i never use as i flush via a drum / bag with the lower unit dropped in)?
 
It's my understanding that the pressure relief valves open to allow more water into the cooling passages. The T-stats are fully open at 160 F, and that's good for trolling and slow cruising, but as the rev's are increased, more heat is generated and the 3 mm openings from the T-stats, on their own, won't allow enough cooling water into the cooling passages in the heads and block. The increase rev's also increases the water pressure from the water pump. Once enough pressure is built up, the pressure relief valves open up, allowing a higher volume of cooling water through.

At least that's how I think it works. I could be totally wrong. Mike? Jimmy? Ian? Jump in here and either confirm or correct my understanding.
 
Thanks, so potentially an area that can't be flushed very easily! I wonder if i could force them open once in a while to get some salt away through?
 
Not sure how the flushing water gets too them. However, if you run the engine in a barrel, rev'ing it up to, say, 3000 rpm should force them open and flush them.

I'll pull out the shop manual and see if I can find additional info. Will post if it is revealing.
 
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