2004 Honda 90 - Small hole in lower unit

Steven Dore

New member
I just discovered a small hole in the lower unit, behind the zinc fitting at the rear of the lower unit. It looks like water may have frozen inside and pushed out a piece of metal about the size of a nickle. There is a white caulking material inside, but the metal is split open. The boat is in dry storage and I have never had a problem draining the water out of the engine previously. It has been three weeks since I ran the boat last, and we have had two nights barely below freezing since it was run and flushed last.

Has anyone experienced a problem like this, and is it repairable without buying a new lower unit?
 
Ask an administrator for a photo album, and post a photo (or post a photo directly/link to your personal album.) If it is in the gear case unlikely to be water--if it is, then you have a seal problem.

The only other zinc I can think of is the trim zinc--and there should not be any water near that area...

All water in the lower leg should drain out, except a very small amount in the water pump--and that should not show on the outside...--and a mild freeze should not cause an issue.
 
Steve,
I have the same issue with my engine. This is a void that holds water in this particular outboard. Maybe it is the water in Portsmouth, VA... anyway I drilled the hole larger and filled it with JB Weld several years ago. I do keep an eye on this, as I change the water pump every 2 years. My boat will be coming out for service in the next few week and I will let you know what I see..
 
Thanks Steve. I can't complain, this is the first real problem I have had with this engine in 14 years. Let me know when you get ready to service yours, I would like to look over your shoulder.

In the mean time, I am going out to buy some JB Weld.
 
Steve,
The first time that I noted this issue was when I serviced the outboard about 4 years ago. I noted it again 2 years ago again, and performed the same repair (JB Weld), the the second time around, I added a bead of adhesive around the void, to prevent water from getting into it at all. This morning when I went for a C-Dory trip, I took a a quick look at the lower unit, and the JB Weld is still in place.
You may remember that I mess with a LOT of outboards as a hobby (yea, I know that that is insane)... Several outboards I have worked on over the last few years, pack voids in the lower unit in the area near the water pump, with grease. I just did a Mere 15 recently that this was called for.
I will be performing complete service on my C-Dory outboard soon, as it is due. Also one end of the steering ram started leaking. I will be replacing the seals in the ram and performing routine maintenance to the O/B including replacement of the water pump.
 
Steve

I would especially like to see the water pump replacement. My engine has a strong stream from the pump, but it has only been replaced once in 14 years. I guess that is because it gets flushed after every trip, but it should probably be replaced when I am repairing the hole in the lower unit.
 
Steve,
Water pumps should be replaced every couple of years, regardless of seeing water come out of the pee hole... Rubber breaks down over time and nothing will preserve it, no matter how many times you flush it. Also another item that fails with time is the thermostat.

Every year or 100 hours, i change oil/filter in the engine, oil in the lower unit, grease all of the fittings and charge fuel filters, lastly pull the prop, remove any fishing line and grease the shaft. Every other year I do all of the items mention in the previous sentence, plus charge spark plugs, change water pump impeller and change the thermostat. Very third year, I check/set valves.

Another problem with not unbolting the lower unit once in a while is that the fastening bolts will eventually not come out, due to corrosion. I use Tef-Gel on all fasteners and use silicone grease on all rubber products to help prevent future fastener problems.
 
Steve Dore,
Tomorrow I will change the water pump in OSPREY. If you can come by, you can witness this simple task. This will give you an opportunity to see the holes in my lower unit that I have repaired (several times).
 
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