12-23-2014, 02:00 PM #1
Just got a 98 GTX Ltd. and going through it. Questions.....
I've had quite a few boats with inboards and outboards but this is my first PWC. Its a 1998 Seadoo GTX Ltd. I am pretty mechanically inclined but had a few questions since I'm new to seadoo's and jet drives. So.... the ski starts and idles good and I ran it on the water briefly (maybe 2mins) just to make sure it ran. Once I did some reading I saw where the grey lines needed to be changed out and all filters cleaned. I've got all the grey lines changed out and man, was there a bunch of crap caked up in the spin off filter and also pretty much clogging the fuel selector valve. I don't even know how fuel was running through that thing. Next I will be pulling off the carbs to clean the internal filters once I figure out how to.
I guess the main couple of questions I had was
#1, what is the easiest way to pull the carbs off to clean the internal filters?
#2, What point on the ski does the water get sucked up into the motor and where should the water be pissing out from?
I want to be sure I have no obstruction of fuel before I actually go ride it and I also want to be sure the cooling system is working as it should. I tested my compression at 135 & 140. I would assume that the ski has had a top end job with numbers like that when the ski has 313hrs on it BUT, I am not sure when it was last rebuilt. I just want to make sure everything is good to go before I start using it (I could actually ride it now since it's still pretty warm in Louisiana). Any tips and advice on what to look for or change would be appreciated.
12-23-2014, 02:37 PM #2
- Join Date
- Jul 2014
Thats a very clean ski, just an added point, did you clean out the fuel switch too?
#1 Im unsure as to your first question, as I own an RFI (no carbs) ski but you might just have to get wrenching. There should be just a few bolts holding them onto the side and undo everything around it. I don't think there is an "easy" way to do it.
#2 the water is forced through the engine through a small hole within the pump (after the impeller), there should be a big thick hose running from the pump area to the end of your engine head. Most of the water comes out of the exhaust and jet pump, but there is a smaller indicator hole near the tow hook. This squirts water from the top of the exhaust (highest point on the cooling route) and therefore if water is coming out there its indicating it should be circulating throughout the rest of the engine. Its not a massive "pisser" but a steady squirt should be seen.
Other tips could be:
What oil are you using? Make sure its a good API TC rated oil and that that is the only oil in the tank. Also how does the oil filter look? You should keep that one in good shape.
Change the jet pump oil (I think yours requires oil?)
Make sure all your electrical connections are clean and strong, incl battery and ground connections, coat with some dielectric grease
Spark Plugs might be due
12-23-2014, 03:02 PM #3
I had one great machine.
The carbs can be removed without removing the exhaust pipe if the pipe to manifold connection is not leaking then don't touch the pipe unless you have to it's a PITA to reinstall. Remove the airbox assembly then remove the four allen head bolts holding the carbs on ( long allen keys are handy get a spare and cut it to length if needed ), slide the carbs backwards then remove the throttle cable, choke cable and fuel lines. I did a carb rejet with Prok flame arresters so no idea what the factory airbox is like it just looks big and cumbersome to me so I deleted it. Even if the pipe to manifold connection is not leaking get the rubber diaper for the connection because if it does start to leak it will spray water into the carbs. Don't clean the fuel selector just get a new one they're cheap enough.
Picture is the rubber diaper installed on my machine.
12-26-2014, 10:40 AM #4
12-26-2014, 10:44 AM #5
12-26-2014, 09:08 PM #6
Got the carbs off tonight. Where are the internal filters located? It's a good thing I pulled the carbs because there was a very small hose cut. Will replace
12-26-2014, 10:27 PM #7
Internal filters are small barrel shaped micro screens located behind the rectangular aluminum covers. Carb diaphragms are behind the squarish steel covers. That nasty goo will be inside the fuel connections on the carbs too. Give them a thorough cleaning and inspect the diaphragms. Remove high and low mixture screws and blow cleaner through the passages. Re-install lows at 1.25-1.5 turns out and highs seated to 1/8 turn out. Inspect the tiny air line on the lower case just under the carb pulse line. There is a short piece then a check valve, then a long piece that runs to the RAVE solenoid. Make sure the check valve works and the short piece is not split or burnt. On the other side directly under the large water inlet line you will find an allen head screw on the lower crankcase. Pull that, being careful not to drop it, then use a q-tip to check oil level. That is the counterbalance lube which sometimes needs checked and even added to. You should also pull the RAVE valves for a cleaning, they get gunked up and if they get really nasty, bad things can happen. I rebuilt five 951 engines this season.
12-27-2014, 06:28 PM #8
Thanks alot. I did everything you said to do with the carbs and I pulled both rave valves and cleaned them real good. They weren't terrible bit definitely needed to be cleaned. The carbs went back on alot faster than when I took them off. When I pulled the cap and spring off of the front rave valve, I noticed the metal spring ring that goes around the rubber had popped off. Nothing was damaged but just needed to be put back on right. The internal filters in the carbs weren't too dirty either but are now crystal clean.
I pulled the Allen bolt and extracted the oil from the counterbalance area. Shop manual says it should have 40ml or 1.35oz but I was only able to extract about 0.3oz from it. So only about 7ml. I didn't have any sae30 oil on hand so that's where I stopped. Gonna try to get some and finish putting it back together tomorrow.
12-27-2014, 10:15 PM #9
Don't worry too much about 1.35oz. That would be a fresh build, there is no way to remove all of it without completely tearing the engine down. Extract as much as you can, then put that amount or a little more back into it. I use synthetic gear lube, the same as what I use in the jet pump......which you should change also.
12-28-2014, 11:34 AM #10
I understand I won't be able to extract all of it but I was only able to pull out 7ml total. 40ml is what was originally in there. 7ml just seems a little low even factoring that some may of burned off over time and that I'm not able to extract every little bit.
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