Outboard Gear oil

[mickjbuist]

Hi everyone,

Just a quick question, I recently had a problem on the weekend where at high revs my motor (1977 35hp Johnson) would fall out of gear, this has never happenend. When i got back home I opened the drain plug for the gear oil in the foot and found the oil to be milky.

What I am wondering is... could the mixture of water and oil cause my driveshaft gears to overheat thus causing my engine to fall out of gear or is my problem much worse?

Thanks guys!

[Noelm]

I guess the only way to tell is replace the oil and give it a run, then replace the oil again, just to make sure there is no water left, you do this after you fix the water leak of course, not too sure water could cause the problem, but funny things do happen sometimes.

[finga]

Did you drain the oil into a pan to see if there was any metal in it?

[mickjbuist]

Yer I drained oil, it was fine just white. I guess I'll just fix the leak and fill it back up. It's ok it gives me an excuse to get out there again this weekend.

[cormorant]

was it going out of gear?? or at higher revs were you spinning the prop hub?

Was it crunching as it went out of gear and stuttering?

Did it "slip back in " when you came off the plane and slowed down?

Oil needs changing and check there isn't fishing line or some obvious seal damage behind the prop. Have a look at eth seal under the waterpump next time it is off.

Spend the $4 and replace the washers under the gearbox oil plugs as they are known points of water getting in if they haven't been changed.

If water is still in the oil after you have flushed and then run it get the box pressure / vacum tested before and after reseal in case you have bent prop shaft or pitting on the shafts etc.

[mickjbuist]

No it isnt the prop. But after I removed the prop i did find oil in the exhaust area so i believe its coming from the housing. Ill see how i go this weekend. I am going to replace all seals etc.

[trueblue]

sounds like a leaky seal

[cormorant]

2 strokes often have oil in the exhaust especially if run on the muffs and at low revs.

Smell and look at the colour of the oil and you will pick up if it is 2 stroke or gearbox oil.

The better oils are a lot more resistant to water and will still offer some lubrication unlike the older oils. So after the flushing oil change it is well worth paying for the better oil since it is a small quantity and keep checking it as gearboxes are not cheap. Doesn't take long for water in a gearbox to damage the needle rollers.

If you dropped the box check the gearchange shaft wher eit goes into the box and make sure it is not jamming and stopping it going fully in and out of gear. Check gear change cables are free as and getting full movement as well since a restriction / stiffness can cause it not to go fully in to gear.