Urgent issue with 1997 Challenger 1800

[Blue in Yarmouth]

Hi Guys,

I'm new here and just purchased a 1997 seadoo challenger last week. It is the first seadoo I have ever owned so I have no experience with jet boats but have used a boat with outboard motor for years. I am also no mechanic so I am really lost with this issue.

When I bought the boat the guy said everything was fine and started the engines to show me that when I got there. Knowing nothing about seadoo's I took him at his word and purchased the boat. We got it back to our home and put it in the water and we couldn't get one of the engines started. The other fired up fine, but the starboard engine just wouldn't go (turns out I flooded it).

I take it to a guy I know who is good with 2-stroke engines and he does a few things and then starts it up fine. We take it back to the water and again, the port engine starts fine, but now the starboard engines starter is gone. We decide to try the boat on the one engine (very short distance...about 50m and back) and it revs fine (reached over 5000 rpm without any problem) but the boat was barely moving. When we would ease off the throttle and the rpms dropped to about 3000 it would go a little better, but once you gave it more gas it would just bog right down.

Having never used a seadoo before I don't know if this is typical behavior for a seadoo on one motor or if it should still work pretty good on one engine. If it is supposed to work fine, anyone have any idea what the issue might be?

Also, I seemed to take on a lot of water on the short trip. I inspected the hull before I bought it and didn't see anything of concern and did again after we got out f the water and still found nothing. Are there areas that seadoos are known for allowing water to enter the bilge? Any tips for a very green seadoo owner would be so much appreciated. I just want to make sure I didn't get terribly ripped off on this purchase....Please tell me these things are easily addressed. Thanks in advance.

 

[Dr Honda]

Sorry to hear about the problems, but you did the #1 thing NOT TO DO, when buying a boat... and that's not taking it on a water trial.


Anyway... you have a few issues. So let's start.

1) Starter. Do not buy an import starter. They all suck. Pull the starter off the bad engine, and if it's an OEM (Denso) starter... just open it, and clean it out. AND... if needed... replace the brushes.

2) Cavitation. Even on one engine, the boat should run OK. (just not as fast) Basically, the impeller is pumping air, and not making thrust. SO... both pumps need to come off, and be inspected. The impellers could be messed up... the wear rings could be bad... or the carbon seals could be bad. (The drivehsaft seals)

3) If all you are getting is 5000 rpm out of the engine that was running... that's not good. Those engines should be running up to 6800 rpm. So... you will want to check the compression.

4) When you run the boat on one engine... you are still forcing water into the cooling system of the engine that isn't running. SO... your non-running engine may be full of water right now. SO... RIGHT NOW... pull the spark plugs, and try to crank it. If it's sitting with water in it... it will rust internally very quick, and that engine will be dead.

 

[Blue in Yarmouth]

Damn...that isn't good news, but thanks very much for your reply. I was hoping to get one of you who really know the boats to respond and I really thank you for that.

One problem is that the engine that wasn't running now has now starter on it so I can't even crank it to get water out. Is there any way that engine won't be filled with water after running for a short time? The plugs are out because when we were trouble shooting why it wouldn't turn over after we took it out we pulled the plugs to try to manually push the piston to make sure the engine hadn't seezed up (which thankfully it hadn't. The plugs didn't seem wet when we did that, but who knows.

After reading your comment about the 6800 rpm I asked my brother (who was actually at the helm when we were testing that one motor as I was in the stern trying to see why we were moving very fast) and he said he was actually hitting 7000 rpm without any trouble, so I guess I passed along some misinformation there.

Again, thanks so much for your help with this. Now I just need to do some research to figure out how to do the things you suggested regarding the pumps and wear rings. Thanks again!

 

[Blue in Yarmouth]

Dr. Honda,

With the cavitation issue I have looked at the impellers while still on the boat and the wear rings. Both look good but I will remove them to get a better view tonight. In case things still look good with those, I am wondering what I would need to do to fix the carbon seals....what parts I need to fix the problem. I have looked at the diagram on the sponsors website and don't know if I only need some of the items or all of them in order to fix the seal. Thanks again for all your help!.

 

[scski]

You'll need to check the clearance on the wear ring with a feeler gauge when you get the pump out.

Carbon seal itself could be worn, bellows may be weak, stainless ring could have some grooves/wear. Once you pull it apart you can see what is bad. Put new orings and clip on the stainless ring.

http://osdparts.com/index.php?main_page=product_free_shipping_info&cPath=2&products_id=4

$80 for the whole thing including bellows, plus s&h.

While you have the driveshaft(s) out, roll on a nice, smooth, flat surface to make sure they are straight.