2003 GTI new purchase issues times 2

[DuramaxSeaDoo]

Hello everybody, I am new here to the forums and really to PWC's in general. I am a master level mechainc (20 years experience) on everything from a weed eater to a Boeing 777, but ive never worked on floating type of things before lol.

So I will start my story from the begining, I am the director of maintenance/lead mechanic for a land scaping company in northern CO and my boss/the owner bought 2 used 2003 seadoo GTI's with the rotax 718 in both. Well she didnt bother putting them in the lake to test, the guy selling them started them on the stand for a couple seconds to show her they worked and that was about it. So after she purchased them and the weather cleared enough to try them out she put one of the skis in the water and it made it bought half way across the lake before taking a crap, they towed it back to the dock and called me in. When i got there i noticed that it started right up but smoked a bit especially the first couple of seconds after start up, to me its pretty bad but after reading several forums it might be normal i guess lol. I went ahead and checked compression right away and found that both cylinders are at 90psi. Some of the info ive found says that 90's fine some says 90's toast, so i told her i gotta do some digging and see whats up so go ahead and put the other ski in the lake and give it a shot. Well that ski at least went twice as far before crapping out lol. After getting that one back to the dock it was missing and stumbling and then as soon as you hit the throttle it would peter out. I checked compression on the engine and its at 48 psi forward cylinder and aft is at 87. I had her bring the skis to my house and i ordered a manual for them. While waiting for the manual i got in touch with the seller of the skis and this is what he told me they did to them before selling: He replaced the pistons and jugs and gasket set on both skis, he did not touch the carbs except to pull them off and then put them back on. He only ran them for about 20 minutes total time after rebuilding the engines and before selling them.

What ive done so far is to pull the carb off of the first ski and checking the diagphram, its crispy, and now im trying to find a carb kit so i can put the carb back together and see if that helps, it should.

So if anybody has any sugestions, questions, comments or whatever let me know . Just keep in mind I am a master mechanic but im a noob on skis lol.

 

[XP 787]

Rebuilding the carbs will not help compression issues. I don't think they were broken in and when you're boss took them out she was unaware of having to do this. I don't think this was her fault unless the PO said something to her.

 

[DuramaxSeaDoo]

No nothing was said to her as far as i know about them needing broken in. Is there anyway to "restart" brake in, if that makes sense? Like should i strip down the 45 psi engine, hone the cylinders and put it back together and start the brake in fresh or is everything pretty much smoked when they arent broken in right? Is the 90psi extremely low for these engines? The reason i was looking into the carb on t6hat engine was the fact that in my experience 90psi isnt to teribly bad so i was hoping replacing the diagphram (it definelty needs one) in the carb and cleaning it all up might help that one run better.

If these were your ski's what would you do to get them up and running?

 

[mikidymac]

90 and 40 psi is very bad on these engines and they will not even start in the water with it that low. With a good strong battery and the throttle held wide open the compression is great at 150 psi and the engine is due for a rebuild at 120 psi. Even a fresh top end with zero hours should be above 135 psi.

DO NOT use a boost box or running vehicle to start them you will fry the computer. Also stay away from the WalMart EverStart batteries.

Why did he do a top end on both of them?

If they had high hours the crank should have been replaced too.

You need to replace the fuel filter under the dash, on/off valve and rebuild the carbs with new kits and needle and seats. The needle and seats don't come with the kits. Make sure you reuse the spring that is in the carbs as the kits do not come with the correct ones. The parts can be found on Amazon.

The manuals can be downloaded for free. Google is your friend.

The only oil you should run in them is API-TC not the blue or green TCW-3.

I have the same ski so if you need any help or questions just ask.

 

[DuramaxSeaDoo]

Thank you SO much Mikidymac, The only history i know on the skis is that they were originally owned by a resort in Cali and then somehow a guy out here got them and fixed them up, they run great on a stand but as soon as you load the engines they fall on their face. I will have to find out if he did the crank or not on either one, i would totally agree that he should have replaced cranks along with the jugs and pistons. Is there anything i can do to try to save the new jugs since they are so low on compression, like would it help to tear them down, rehone the cylinders and reassemble the engines? The one with 90 on both cylinders feels good thats why i went for the carb on that one right away. Im not sure what kind of oil they put in them but it is definetly blue, so if thats not what should be in there i will drain the tanks and get the right stuff. Could the wrong oil be whats causeing the first ski (90 psi both) to smoke?

Also I know theres the fitting on the back of the skis to hook a garden hose to to be able to run them out of the water but ive also been told that the drives will overheat really quick if running them on a hose. How long can i run them being hose feed and is there any way to hook up a second hose and maybe have it feeding into the water intake, would that help them not overheat?

 

[XP 787]

Don't run on hose for over a minute. Lake water lubricates and cools the carbon ring. Do another compression test just to verify you're original readings then pull the heads. A ski with low compression will sound great on the hose (no load) as soon as you put them in the water they fall on their face. Unfortunately it sounds like both engines will need a full rebuild.

 

[DuramaxSeaDoo]

XP 787 thats what i was afraid of. The other thing that worries me is that the guy that sold them to my boss said that he had run the skis on the hose for 10-15 minutes, so im worried he screwed the pooch all the way around on these but hopefully i can pull something outta my butt lol. Is Amazon the best resource for parts for these things or is there another online source you would recomend? For both prices and quality, i dont mind spending a bit more for way better quality type of thing

 

[XP 787]

Try SBT (Short Block Technologies) out of Clearwater. They have rebuilt motors if needed and a wide array of parts. I am sure there other companies but I have never dealt with them. I am sure more experienced members will chime in and give you some other options. http://www.shopsbt.com/