25hp Honda water in lower unit oil

I don't know much about outboard motors I just bought a2000 25hp Honda.I put it on my boat and noticed milky looking oil coming out of a port in the lower unit. What's going on

You have gear oil in The lower unit and you have engine oil in the motor. Both can get milky if water is entering and your engine exhausts through the prop meaning what you are seeing on the lower unit could potentially be either. Its not easy to tell from your explanation which oil is getting milky that you have noticed. You need to check the oil in both for condition. There is a large faced screw on the bottom side of the lower unit (Fill) that you can unscrew and check for water or contaminated oil, hold a clear glass jar under this to capture oil for inspection. On the motor you can check the dipstick under the cowling for the condition of the oil. Once you narrow it down we can help determine what remedies may be available to you. Do not run your engine in its current state as you risk causing catastrophic (read expensive) damage. It might be as simple as removing some old tangled fishing line or it might be very much worse, we are here to help you figure that out.

skronkman said:

You have gear oil in The lower unit and you have engine oil in the motor. Both can get milky if water is entering and your engine exhausts through the prop meaning what you are seeing on the lower unit could potentially be either. Its not easy to tell from your explanation which oil is getting milky that you have noticed. You need to check the oil in both for condition. There is a large faced screw on the bottom side of the lower unit (Fill) that you can unscrew and check for water or contaminated oil, hold a clear glass jar under this to capture oil for inspection. On the motor you can check the dipstick under the cowling for the condition of the oil. Once you narrow it down we can help determine what remedies may be available to you. Do not run your engine in its current state as you risk causing catastrophic (read expensive) damage. It might be as simple as removing some old tangled fishing line or it might be very much worse, we are here to help you figure that out.

Click to expand...

The engin oil is fine. It's the gear oil in the lower unit

Ok then it sounds like you have a seal problem. The first and easiest place to check is take off the prop and look for fishing line around the prop shaft. This will damage the prop shaft seal and allow water in/oil out. Also another easy check is the fill and level screws on the side of the gearcase, they should have good condition nylon (soft, white plastic) washers to seal when tightened. Try these and an oil change and see if it gets better, if not the. It's time to look at replacing seals.

By the way, if it does come to replacing seals then it is something a mechanically minded person can do but if that's not you then take it to an outboard shop and have them replace the faulty seal and check the condition of the other seals (replace as necessary). Then they should do a pressure test (and possibly a vacuum test). The parts are not expensive and it should be 1-2 hours work.

skronkman said:

By the way, if it does come to replacing seals then it is something a mechanically minded person can do but if that's not you then take it to an outboard shop and have them replace the faulty seal and check the condition of the other seals (replace as necessary). Then they should do a pressure test (and possibly a vacuum test). The parts are not expensive and it should be 1-2 hours work.

Click to expand...

when I transported it I had to lay it on its side (I made sure it was the right side) when I got home white ,grayish colored oil was coming out of a small hole on the lower unit

Ok. Well it's possible you don't actually have an issue at all if it was only a small amount and it seeped out while the engine was laying on its side and not running. You need to check the colour of the leg oil as described above to be sure though. The checks i mentioned above cost nothing and are easy to do. Better safe than sorry. Oil, grease, water, fuel, dirt get all over outboards and mix and when you tilt it over sometimes a small amount that was being cupped in the upright position will leak out of unusual places. Greyish slime on the outside is less indicative of a major issue than cafe latte coloured oil on the inside.

with engine in an upright position remove drain and fill screws, and drain the gear oil that is contaminated.
let it drain completely and check the magnetic plug for metal particles
replace the gaskets and refill with new gear oil.
run it for a couple hours, let it sit a while and then remove drain plug only.
If its still milky it could be prop shaft,shift shaft or drive shaft seal.
vacuum test should show you where the leak is.

I have to agree with the others....drain the gear case oil and see what you have going on in there. It is something to do that is always a good idea if you buy a used outboard. It can offer you peace of mind if the oil is just dirty (dark or black) and it can save you a "boatload" of money if it is contaminated and you are catching it before any transmission damage takes place.

If it's just dirty...you did your first gear oil change. If it's contaminated....you have started finding out what it takes to be an outboard owner...they all leak eventually. The sooner the fix is done, the less it's likely to cost.

Good luck.

P. S. refilling a gear case requires that you fill it from the DRAIN HOLE until oil runs out of the FILL HOLE. Sounds backwards, I know, but that is how it is done or you will probably never get it completely full. It can be a MESSY and somewhat frustrating job for the first timer. There are some tricks for making it go smooth though.

1. Do it in a place you don't mind getting a little oil spilled on or cover the surface according to your "neatness criteria".

2a. There are two ways/methods for most of us...You can purchase a pump style bottle with a hose and a little adapter that is supposed to fit into the DRAIN HOLE. The problem is...these almost NEVER fit a HONDA! :~(. But, if you like the idea of having a reusable container and pump to do this chore in the future, you can modify the fitting to meet your needs. It CAN work.

2b. The "other way" is the "old way" and works pretty good. The gear oil is sold in little half pint tubes that have a tip that you "cut to fit" the DRAIN HOLE. You then simply insert the tube into the hole and squeeze the oil up into the gear housing. This takes some technique in that if you don't efficiently roll the tube up (like a toothpaste tube) while you are squeezing, the oil has a tendency to want to get sucked BACK into the tube. Also, there is NEVER enough oil in ONE tube to completely fill the case. You need at least two tubes which means, at some point, you have to stop and get another tube stuck up into that DRAIN HOLE. And, OF COURSE, that is when all the oil you just put in wants to DRAIN BACK OUT OF THE DRAIN HOLE! This is where step 3 comes in.

3. THE TRICK! The trick to EITHER method is that, when you reach a point that you need to "punt"...IE: change tubes, reassess, take a break...drink a beer....the trick to doing this without ALL the oil trying to come back out of the DRAIN HOLE is to put the FILL PLUG into IT'S HOLE! I actually have some little "rubber stoppers" that work nicely for doing this but the FILL PLUG works good too. Doing this has the effect of causing an air or "vapor lock" to take place inside the housing. it won't keep 100% of the oil from escaping but will slow the drainage down drastically so that you can grab the DRAIN PLUG or a rubber stopper or a small rag or a sharpened stick or ANYTHING to put in the DRAIN HOLE to completely stop the flow. The more oil that is in the case, the better this method works. So, if you can coax MOST of the oil out of the first squeeze tube up in there and then temporarily install the FILL PLUG you can easily grab the DRAIN PLUG and put it in to prep your next squeeze tube.
BUT...there IS a CATCH!

4 THE CATCH. The TRICK will not work well on a unit that has a LEAK from one of the shaft seals. The LEAK will not allow an "AIR LOCK" to take place. So....IF you have a leak, the first indication will likely be the "cafe latte" that skronkman mentioned. The other is that, when you go to drain the case, loosen and remove the DRAIN SCREW ONLY. If there are NO leaks, then the oil should look dark brown or black and it should NOT want to come out of the case into your drain pan except in dribs and drabs. If one of the seals is leaking then the oil will readily drain from the case with the FILL PLUG still firmly seated.

I hope this is helpful and not confusing....Long winded for sure, but...when you finally get to the end...it is info I wish I had on my first go round.

Good luck.