1997 GTX - How to flush/clean the oil system?

[donnie5336]

Hey guys, I recently picked up a 97 GTX. Had to replace the start/stop switch on it and it runs like a dream. 221 hours on engine, the top-end has never been into, and has 150 psi on each cylinder still. The previous owner said he had been running Pennzoil synthetic blend oil in it (blue). Obviously it is still performing well but I would like to change over to the SeaDoo synthetic XPS. What all do I need to do? I don't want to ruin a good running engine by not cleaning everything I should and oils not mixing and causing problems somewhere.

I've read some posts that say just clean the tank and lines really good and you will be fine. Some said clean rave valves and injectors. Can somebody point me in the right direction of everything that is needed when changing oils?

 

[CReynoldsMIZ]

This is the no mess, best way to evacuate your oil system and start fresh.

First, go out and buy you one of these fluid transfer pumps. About $7 from walmart or harbor freight

https://www.harborfreight.com/multi-use-transfer-pump-66418.html

Stick the hose into the oil tank, and proceed to suck all of the oil out of the tank. Once all of the oil is out of the tank, the next thing you will notice is you will still have oil in the rotary "oil bath" lines that go to the engine. Trace and find the "oil return" line that goes from the side of the engine behind the exhaust (the side opposite the carb's) and you will see that line will go and return to the top of the oil tank. Pull that line off of the top of the oil tank, and connect that line to your transfer pump and then you can pump the rest of that old oil out of the engine.

At that point you will see that both of the lines that connect to both sides of the engine should be empty, but you will still have some in the line that connects to your oil pump. Go ahead and pull off the line at the oil pump connection, and do it quick so you don't spill a bunch of oil in the hull. Once you have done that, go ahead and disconnect the remaining line from the tank that feeds the rotary valve, and pull out the oil tank so you can clean it. Put some gas in the oil tank and slosh it around and the oil tank should come out crystal clean. Put a new oil filter on the line that feeds the pump, and then reinstall everything how it was with fresh XPS Synthetic oil or whatever you like. Doing it this way is the least messy way you can do it, and ensures it is as clean as can be. Make sure to open up the bleed screw on the oil pump to get the air out when putting new oil in, and I recommend changing out the small 3/32" oil lines that go to the carburetor as well!

Good luck!

 

[donnie5336]

Thanks for the detailed reply! So as long as everything is drained well and the tank is thoroughly cleaned, there's no need to flush the oil pump, rotary valve, etc.?

 

[CReynoldsMIZ]

Nope you should be fine. That being said, when you fill the tank back out, it may push some of the left over residual oil out into the return line that goes back to the top of the oil tank. That line never really circulates, it just creates a bath. Like I said the new oil may push some of the left over old oil that didn't get sucked up out, so if you want you could suck that last little bit of old stuff out but it wont hurt anything. There may not even be enough to notice honestly

 

[mikidymac]

If it were mine I would suck as much of the old stuff out of the rotary cavity as I could. Some here have had the TCW oil cause crank seals to leak.

 

[GloryDayz]

Nope you should be fine. That being said, when you fill the tank back out, it may push some of the left over residual oil out into the return line that goes back to the top of the oil tank. That line never really circulates, it just creates a bath. Like I said the new oil may push some of the left over old oil that didn't get sucked up out, so if you want you could suck that last little bit of old stuff out but it wont hurt anything. There may not even be enough to notice honestly

Thanks. New to this forum.. Just got my first (used) 2000 GTI Seadoo and have learned a lot. I fixed the oil tank (the polyethylene melt/weld deal [and it worked perfectly too]), but after reading everything about needing to bleed everything I was concerned when I saw air in the port-side return line.

So, a lot of cleaning into it, a new battery, and a new fuel sensor tube on order (the magnets were there, so the F1 fuse looks to be shot - and I'm not up for that hack!), I think this puppy is ready to be put through its paces...