Final update towards the bottom of p3.


Saltwater and I don’t have time to address it at the moment. Can I/should I take the spark plugs out and spray some oil of some sort in the cylinders to prevent them from rusting until I can get at this in a week? 30HP Suzuki.

This message has been edited. Last edited by: trapper189,

If it’s only a week I’d not worry about it. If you were in northern climates and it was going to be months then Id say yes

I would drain the oil, install new oil and filter, and run the engine using fresh water. If you have time, do this more than once. Cylinders are one thing, but crankshaft bearing surfaces must be maintained to the highest standard.

You may have to flush the engine using 1 part diesel fuel and about 5 parts engine oil. Jump on it, do not delay.

I think my boys blew the head gasket. Yesterday, they took it out for 45 minutes. They called me 10 minutes in to tell me the over heat warning light was on and the motor went in to limp mode. I asked if the motor was peeing, my son looked and that’s when he realized he forgot to reinstall the flush port plug after flushing it the day before. He put the plug in, I had him wait 10 minutes before restarting the motor, he said the light was out, and they ran around a bit. They both thought the motor was running fine.

I checked the oil this morning and it seemed fine. They went out for a couple of hours, said it ran fine, but when we flushed it using the flush port (motor not running of course) water seemed to be coming from places I never noticed it coming from before. I pulled the dipstick and the picture in the first post is what I found.

I’m thinking the head gasket is blown. I have a big garbage can I could run a hose into, but should I really do this before fixing the head gasket?

No, may as well pull the head. If the boys are not too young, I would have them learn how to do it. They will then be more careful, and the learning experience will help them greatly in the future.

He’s 15 and he’s going to fix this as it’s a lesson he needs to learn.

We just can’t get to it this week, hence should pull the plugs and spray digging oil in or something? Like I said, it’s saltwater. I can drain the oil, refill and repeat easy enough. It’s a four stroke and there’s a lot of work to remove the cylinder head.

I would make time. Saltwater in an outboard is not good.

whats the motor? A 30hp what?

^^ Outboard, Suzuki, 4-Stroke

If it is one of their older early 4 strokes I don't think it is worth investing a lot of time and $ on. ymmv

2019 with less than 50 hours. About $5,000 for a new one.

Drain oil and at the minimum replace with fresh oil. Most likely has a hole in the block somewhere since it's a Suzuki, but you might get lucky.

Let us know how this turned out when you get into it.

^^^Will do.

Bought my 15yo a set of tools, a jug of Supertech 0w-16, and a $3 drain pan. The first drain:


Spark plugs looked perfect, so we filled it with oil, pulled the rope a bunch of times, put the spark plugs back in, ran it for 10 seconds and drained it again. Still some milky crap came out towards the end. We filled it again and are going to let it sit until after Christmas.

quote:

Originally posted by jimmy123x:
Drain oil and at the minimum replace with fresh oil. Most likely has a hole in the block somewhere since it's a Suzuki, but you might get lucky.

In a 30hp tiller motor? I guess a compression test is in order then to rule out the head gasket.

Bought a compression tester and ran the engine a few minutes in a garbage can full of water to warm it up. All three cylinders are 185psi with me pulling the pull start 5 or 6 times.

I’m honestly not sure I learned anything or ruled anything out.

Checked the thermostat as well. It looks good and isn’t stuck open. Opens in boiling water and closes in cold water.

This message has been edited. Last edited by: trapper189,

Cross leaking between a coolant passage and a oil passage? Maybe that head gasket was “on the edge” at the passage and the overheat was enough to drive it over the edge.

It is often easy to have a leak between an oil passage and the cooling system. Cylinder compression does not have to be bad.

When I worked on inboards that had saltwater in them. First we would drain, add oil often a small amount of diesel fuel. Then run for 5 minutes, drain, add regular oil, run for 5 minutes. That will hold you for 2-3 days. Ideally change the oil 4-5 times.

Thank you. So water isn’t getting into the combustion chamber but rather directly into the oil which a compression test wouldn’t show. I should be able to test that by booking a hose to the flush port and flushing the engine. I’ve drained the oil again, so it should be obvious if bunch of water comes out the oil drain.

quote:

Originally posted by trapper189:
Thank you. So water isn’t getting into the combustion chamber but rather directly into the oil which a compression test wouldn’t show. I should be able to test that by booking a hose to the flush port and flushing the engine. I’ve drained the oil again, so it should be obvious if bunch of water comes out the oil drain.

Suzuki's are notorious for not having great metallurgy and issues like this are common. Do yourself a favor and buy a new motor, chances are there's a hole rotted in the block and getting into the oil passage. You could pull the head and try to find it and JB weld might get you some more time.

50 hours, flushed every use, stored indoors, the zincs are spotless, so I’m going to put a little time into finding the problem before I drop $5k on a new motor.

Today, I let it idle for 20 minutes in a 50 gallon garbage can full of water. The oil looks perfect. I’m going to run it on the river tomorrow for a bit and see if the water returns.