How to get gear oil into an outboard

[peter2407]

This is a Tohatsu 3.5 with Forward/Neutral gears. I drained the gear oil last year thinking I could do the full service, but failed to do so (so many reasons). Checking the manual it says drain the gear oil via the lower plug when the O/B is upright, and to re-fill use a squeezy gadget think that I dont have via the lower plug until it flows out of the upper plug. I improvised with an icing bag and a straw, but .... the O'B is lay at a 45 degree is angle to vertical (up) and I have squeezed more than the required 180 mL no tell tale at the top. I know lots of oil is on the drive and not in the gear box, but any advice? I dont want to risk the gear box cos the O/B is usually reliable. In this position I am getting 'squeeze back' from the lower plug. How can I tell if there is/isnt enough gear oil without risking the gear box.

 

[sailorman]

use the tube inside the screw cap on the bottom hole

 

[Poey50]

Whatever squeezy thing you use it is always better to do it with cold oil - so (as I generally do it over the winter) I leave the oil outside overnight. It doesn't run out so easily then. Obviously the opposite applies when you want to drain the oil and the engine then gets a rare night indoors beforehand.

 

[VicS]

This is a Tohatsu 3.5 with Forward/Neutral gears. I drained the gear oil last year thinking I could do the full service, but failed to do so (so many reasons). Checking the manual it says drain the gear oil via the lower plug when the O/B is upright, and to re-fill use a squeezy gadget think that I dont have via the lower plug until it flows out of the upper plug. I improvised with an icing bag and a straw, but .... the O'B is lay at a 45 degree is angle to vertical (up) and I have squeezed more than the required 180 mL no tell tale at the top. I know lots of oil is on the drive and not in the gear box, but any advice? I dont want to risk the gear box cos the O/B is usually reliable. In this position I am getting 'squeeze back' from the lower plug. How can I tell if there is/isnt enough gear oil without risking the gear box.

Thats the way its done but normally with the engine upright. It's important to fill from the bottom to avoid air locks preventing you getting the right amount in

You need a squeezy tube of oil with a nozzle that will fit into the lower hole. Squeeze until oil flows from the top hole. Quickly refit the top plug , using a new seal. Then remove the tube of oil and quickly fit the bottom plug with a new seal.
With a little practice you should be able to do it with very little oil spillage

I bought just one batch of oil in a squeezy tube and subsequently refilled it from a larger container.


You should be able to buy a little hand pump to fit the drain/ filler hole, if you really want to, from your Tohatsu dealer

However if you think you have put at least the correct amount in refit the drain plug. stand it upright and allow any surplus to run out of the level hole. If none runs out you did not get enough in. Try again.

 

[DownWest]

There are some cheap plastic bits from the chandalries to do it, But i just found a big syringe that had the right size nozzle to screw into the 3/8" hole. Bit of wastage, but not enough to justify buying a dedicated pump.
Do it upright, until the top level hole ouzes oïl, then put in the top blanking screw, whip out the lower filler and get the screw in quick. As above, cold oïl makes getting it in slower, but loses less when putting in the plug. Reality is, not a lot gets wasted.

Crossed with VIc, the guru

 

[peter2407]

Is the issue that I bought the gear oil from Halfords, ie matches the spec except for the 'marine' bit? Does it matter? The bit I dont understand is why I am getting 'squeeze back' on the lower hole but not flow from the upper?

Also, the top bung is marked as 'oil level', but is this actually a sump, ie that the gear area is higher up?

 

[VicS]

Is the issue that I bought the gear oil from Halfords, ie matches the spec except for the 'marine' bit? Does it matter? The bit I dont understand is why I am getting 'squeeze back' on the lower hole but not flow from the upper?

Also, the top bung is marked as 'oil level', but is this actually a sump, ie that the gear area is higher up?

No problem that you have bought automotive oil provided its the correct viscosity except that it will not contain the emulsifiers and corrosion inhibitors which ( they tell us) are in an outboard gear oil to protect against the effects of water ingress. It won't of course be in a squeezy tube like the one I have shown above. The whole point of that is that the spout fits into the drain/ filler hole tightly

I am wondering just what screws you have taken out The drain is at the bottom of the bulbous part of the gearcase, which is where the gears are located. The level plug is immediately above the AV plate. They are clearly illustrated in the owner's manual,