Lower Unit Fluid Troubles

[guisertj]

I went to change my lower unit fluid tonight with Quicksilver Lower Unit fluid and a Quicksilver pump that I bought at Walmart. After letting the unit drain for about 20 minutes, I was ready to pump in the new fluid. While trying to thread in the pump into the bottom drain hole, the pump end would not thread in, it was larger than the hole. The previous owner had the lower unit rebuilt and possibly replaced which could have answered why the hole was small since the pump said that it would fit Johnson outboards. I pumped in what I could until fluid was coming out of the top hole. The thing that concerns me is that I only pumped in about half a bottle, if that. Is that enough, or do I need to try again with a different type of pump?

 

[tx1961whaler]

Re: Lower Unit Fluid Troubles

If oil came out of the top vent hole, then it is full.

 

[Mas]

Re: Lower Unit Fluid Troubles

Be certain the the fluid that you removed was not milky...which indicates water intrusion. Golden fluid like honey is the best, but the lube can get darker with age and wear....but not milky. Be sure to use NEW plug washers, using the old ones is often a cause of water intrusion which will ruin your lower unit!

MAS

 

[guisertj]

Re: Lower Unit Fluid Troubles

Fluid that came out looked good. No milkyness. When I removed the plugs there were no plug washers. I plan to find some at a local marina and put them on. The big thing that concers me is that it didn't take much fluid at all to fill. Could there have been an air pocket or possibly not all of the fluid drained out?

 

[Mas]

Re: Lower Unit Fluid Troubles

If you didn't have washers, then your L.U. will have leaked! Maybe your plug had an O-ring instead?

MAS

 

[ezeke]

Re: Lower Unit Fluid Troubles

Both plugs should be the same and the same size. What motor is it? Are you sure you removed the fill plug?

 

[Mas]

Re: Lower Unit Fluid Troubles

Oh ya, the plug washers are usually made of plastic...not metal. Again, as said earlier, when oil is coming out of the top vent, it's full. Make sure you are filling from the bottom drain plug by forcing oil in up through the top vent. A pump is usually the best way to do this!

MAS

 

[tashasdaddy]

Re: Lower Unit Fluid Troubles

depends on the size bottle and the motor you have, what are both??????

 

[guisertj]

Re: Lower Unit Fluid Troubles

Johnson 175. I was using a quart bottle. I am pretty sure that there was no o-ring or washer. I will look again tonight. Along the lines of the different pumps, I saw one at BPS that came with a metal adapter. It looked as if it screwed on the end of the plastic adapter to fit into a smaller opening? Does anyone know anything about this pump and if it does indeed do that?

 

[ezeke]

Re: Lower Unit Fluid Troubles

The smaller, older V6 cases held around 26-28 ounces.

The newer, larger V6 cases hold 30-33 ounces.

 

[ezeke]

Re: Lower Unit Fluid Troubles

The standard Mercury fill and vent plugs and the J/E plugs are the same threads. The fill plug is at the bottom of the rounded part of the gearcase.

The older V6 gearcases held 26-28 ounces, The newer, larger V6 cases held 30-33 ounces.

 

[jonesg]

Re: Lower Unit Fluid Troubles

The quicksilver pump should come with a couple of adapters.
If theres an air pocket try rotating the prop in gear.
Depending where you live this ain't exactly great weather for trying to drain thick oil.

Check the level again when you get the screw seals.

 

[jasper60103]

Re: Lower Unit Fluid Troubles

I bought a cheap pump for filling my johnson LU. Not sure of the brand, but the pkg said it fits johnson 3/8" plug holes, which I assumed meant all johnson/rude. Turns out it didn't fit mine. It was too large, but it did thread in about a full turn which was good enough to fill w/o leaking. Just be careful and don't try to force it.

I have a different motor, but mine took a pint of oil as well, which was about the same amount that drained out. Also, regarding the nylon washers, they tend to stick in the plug/vent holes when the plug is removed and w/o enough light you can barely see them.

 

[guisertj]

Re: Lower Unit Fluid Troubles

Thanks for all the help. I think I am gonna giver her another try this weekend.