1996 GTX- How to Premix question

[Irrumater]

Recently purchased my first Skis, a 1996 GTX 787 and a 1992 SPI with a motor swap to 717. After a few weeks of tinkering (and a lot of help from the great people on this forum). I have them both running and hope to get them to the lake for a first water test this weekend.
I can tell that the PO did a premix conversion on the SPI as the oil pump is laying in the bottom of the hull and I found the input nipples capped off. The GTX looks to be intact but there was old premix gas in the tank when I drained it. I contacted the PO and he confirmed he ran premix. SO premix it is in both at least for the time being and I figure out how to confirm if oil injection is working or not in GTX.
My question is HOW to best handle that volume of premix, and of course be able to refuel? Do I have to use Jerry cans and mix 5 gallons at a time, or is it possible to fill the tank and add oil directly? It looks like the GTX has about a 15 gallon tank, and the SPI 7 gallons so 5 gallons at a time will be a pain.
I can not seem to find a straight answer anywhere so I am looking for suggestions of what others do.

 

[POPPS]

Ideally, you put fuel in,,,see what the meter on the pump says,,,do your math,,,have a longer snout to enter the gas opening,,,and add extra oil to compensate for oil sticking loses in the snout and gas filler hose,,,that’s much safer than doing the opposite,,,guessing the oil,,,based on the fuel gauge,,doing the math,,,then adding the appropriate fuel.

 

[mikidymac]

Well you really can’t easily convert these to premix and most people do it wrong.

You have to make sure you still supply the rotary gear with oil even with premix so you better make damn sure you are.

For premixing yes you need to do it in gas cans. You can’t just dump oil in the fuel tank and think it’s going to mix or be accurate. You can’t just say it looks like I have half a tank, pump in 4.28 gallons until the nozzle clicks off and dump in 7.5 ounces of oil and guess it might be close enough.

Get a 5 gallon jug and a Maxima Quick 2 Mix bottle to measure the oil ratio.

 

[Orbitalatx]

The 96 gtx 787 holds 15 gallons of fuel.


I would go 40:1, some people run 50:1 just fine, but to be safe for a trip just run 40:1 it's more oil and more piece of mind. A quick premix app can be downloaded on your phone or just do the math ahead of time. But always leave space to add the oil. Don't fill the tank to 15 gallon you'll overflow it (experience on this) and won't have room for the oil! Fill to about 14 gallon, stop gas pump, measure out oil, pour in oil, top off ski. By the time you get to the lake it should be mixed up good. It will smoke but that's good you know the oil is good.

 

[Irrumater]

The 96 gtx 787 holds 15 gallons of fuel.

View attachment 59087
I would go 40:1, some people run 50:1 just fine, but to be safe for a trip just run 40:1 it's more oil and more piece of mind. A quick premix app can be downloaded on your phone or just do the math ahead of time. But always leave space to add the oil. Don't fill the tank to 15 gallon you'll overflow it (experience on this) and won't have room for the oil! Fill to about 14 gallon, stop gas pump, measure out oil, pour in oil, top off ski. By the time you get to the lake it should be mixed up good. It will smoke but that's good you know the oil is good. View attachment 59088

That sounds like what I was hoping I could do. calculate based on gallons from pump and add oil, shake well by driving. Thanks

 

[etemplet]

3.2 ounces per gallon. Read the pump and multiply. It ain't rocket science and your phone has a calculator. Stop the pump on an even gallon and go with it.

Ever mix 3 cans and say, "Hmmmmm.... did I add oil to that one?? Or not have enough oil on hand after you filled the ski with gas at the station. LOL

 

[mikidymac]

That sounds like what I was hoping I could do. calculate based on gallons from pump and add oil, shake well by driving. Thanks

You are not going to get a good mix by dumping the oil into a 15 gallon tank but it is your engine so I wish you the best.

40:1 do not use 50:1.

 

[etemplet]

You are not going to get a good mix by dumping the oil into a 15 gallon tank but it is your engine so I wish you the best.

40:1 do not use 50:1.

We put additives in aircraft fuel the same way. 1 ounce to 10 gallons. Like Ragu.. "it's in there."

 

[Orbitalatx]

I drive like I'm back in Iraq so lots of hard stops lead foot etc I'm surprised the ski is on the back when I get to the lake lmao.

 

[Venturian1]

Recently purchased my first Skis, a 1996 GTX 787 and a 1992 SPI with a motor swap to 717. After a few weeks of tinkering (and a lot of help from the great people on this forum). I have them both running and hope to get them to the lake for a first water test this weekend.
I can tell that the PO did a premix conversion on the SPI as the oil pump is laying in the bottom of the hull and I found the input nipples capped off. The GTX looks to be intact but there was old premix gas in the tank when I drained it. I contacted the PO and he confirmed he ran premix. SO premix it is in both at least for the time being and I figure out how to confirm if oil injection is working or not in GTX.
My question is HOW to best handle that volume of premix, and of course be able to refuel? Do I have to use Jerry cans and mix 5 gallons at a time, or is it possible to fill the tank and add oil directly? It looks like the GTX has about a 15 gallon tank, and the SPI 7 gallons so 5 gallons at a time will be a pain.
I can not seem to find a straight answer anywhere so I am looking for suggestions of what others do.

Why not Put the injection oil pump back on, and connect the hoses? You have to leave the oil tank in anyway to supply the rotary valve shaft with oil. I had worked on a 657x
with a bad oil pump, and decided to go
pre-mix, so I contacted Bombardier to find out the best ratio and type of oil. It’s called a variable rate injection pump, and was told that the ratio changes with RPM. At top speed it’s getting like 20:1, and at idle it’s like 100:1, and the best type of oil....full synthetic, synthetic blend, mineral oil, depends on your model, & year. I found a replacement pump on eBay and use full synthetic now.

 

[Irrumater]

I am currently planning to after this season. I am trying to get on the water and enjoy them, and then this fall/winter I am planning to go through them alot more, possibly pull the engines etc.
Oil pumps ate on that list