gearbox oil change

[Guest]

I've been struggling to change the oil in the gearbox. Tried sucking it out with a surprise surprise, probably the correct tool, a gearbox oil suction pump and it will only get about 500 ml. The drain bolt is underneath and to one side but the acess is atrocious, probably why I've got gearbox problems because of the difficulty in changing the oil. Just wondered if there is a product like a bent tube that can be screwed into the drain and come up and around the bottom of the "box" to ease the access? Thanks.

[Steve Pope 243]

I plumbed an elbow into my drain plug outlet before installation. there is also an after market drain plug that has a spring loaded ball that keeps the oil in until you screw in the drain hose. Rather like a garden hose fitting, except in metal and much better made.

[wheels 543]

All Boat biulders should be made to do the first oil change on the boat they biuld. It wouldn;t take too many boats before they start thinking about making better access to the drain bungs on Engines and Gearboxes.

There is nothing off the shelf I know of. You might have to make something BBay. I fitted a ball valve and tail to take a hose, to the bottom of the sump on my engine. Then I put an oil suck pump on and suck the oil right from the bottom.

[Guest]

Thanks Steve, Wheels, Guess the best way is to go to an engineer and say please fix it. I did manage to do the oil change this evening but it took a lot of blood and skin! At one stage I thought I was stuck head first in the bilge, took a while to find some thing to grab to hoist myself out I had to take the muffler off to get better access and a bit of swing room.

Thats not the end of it though, went to change the impeller and found the impeller shaft as loose as a stoned hippie. Luckily I've a spare pump on board so just a matter of changing the hoses as slightly different diameter required.

I've had the entire cooling system off and acid bathed, head off the engine and reconditioned due to the gasket leaking coolant, just got that back on day before yesterday. The head cost $425 to have tested, skimmed and valves lapped. Gasket kit was $75 plus $50 delivery( from Greece!!).

It will be interesting to see if the gearbox behaves a bit better with clean oil. This is the third time I've changed it this summer and it is filthy every time though getting better. At least it looks like oil now and not the rusty water that came out when I did the first change.

I'm going to see if I can get the old chook to give me a massage .

[Steve Pope 243]

Bbay what sort of engine/gearbox do you have, if the box is hydraulic and the oil is coming out black it is possibly a sign that the clutch plates may be slipping. Gaskets from Greece, Where are you??

[Guest]

You mentioned the gearbox oil looked like rusty water - if you have a gearbox oil cooler then they are notorious for corroding and pin-holes letting cooling water in, then as the gearbox fills up, letting the oil out into the cooling circuit until you end up with water only in the gearbox and rapid damage. Most gearbox oil coolers are raw water cooled for some reason. If you have a small mechanical gearbox (vs hydraulic) then it probably won't have a cooler.

[wheels 543]

Yes his gearbox was slipping badly. I think the rusty water/black oil thing was the engine oil.

[Guest]

Thanks Pohopetch, yes I've checked the cooling system out and It seems good. It was not actually water that came out of the box but a substance with about that viscosity and a rusty colour. It was oil at some stage. i'm guessing the difficulty of getting to the sump plug hindered good maintenance. Need long thin arms and small hands and an extra arm and hand would definitely help. The oil that came out today had bits of sludgy stuff in it, there were also some metal filings around the magnet on the sump plug though not a lot. It is going a lot better now than when i first bought her. 8 metre seas here in gissy this weekend so won't be going out to try it.