Speedster SK 717 Pngine / Pump Problems - PLEASE HELP

[photo4286]

Hey guys just picked up a Seadoo Speedster SK w/ dual 717 engines in it. Having a few problems and was wondering if you could help me out.

Engine 1 (left) doesn't want to idle, but runs ok once I got it going. It takes alot of choke and throttle to get it started. The engine could definitely run better (Could this just be the idle on the carb?). Also seams to run 200 - 500 rpms lower than its counterpart between mid a full rpms

In general the boat maxed at 40 mph (using gps for measurment). From my understanding this boat should make it up to 50 mph, so something is not performing correctly....The left engine was rebuilt in 06'.....Any Ideas

There is a lot of rattling during hard acceleration. To be more specific about the heavy rattling. It is worst when the engine is stressing to get into a plane, and then it levels of to normal after you are at top speed and planing.

Could this be the pumps? It says that the left pump is new in winter of 09....Could it be the drive shafts, etc????

What do you guys think? On top of all this are there any normal problems I should look out for and get ahead of.

I could really use the help, I was hoping to work on it tonight, and also anything long term will have to be ordered.

 

[Dr Honda]

Welcome,

Well... it's kind of hard to pin point what you are asking about.

Rattling under a load is bad. Depending if it's metallic, or a rumble ... I would look for a broken engine mount, or missing exhaust bolts. It could be something simple... but it could be bad too.

Seadoo's are know to have noisy pumps... but that's normally at an idle.

The hard to start issue....

I would start with raising the idle a little, and make sure the throttle butterflies open the entire way. AND... that they are in sync with the other engine. (ie... half is half, and full is full)

Since it's a new-to-you boat... I would check compression on both engines.

Let us know what you find.

 

[staceyrides]

Dude,

Whatever you do, get that sorted out before it leads to a bigger problem.

I just bought a 97 speedster 3 weeks ago and noticed the port (left) engine would rev much quicker and even lose power on occasion under acceleration. After talking with several people, I figured I had a cavitation issue but was told that I wasn't in real danger of harming the engine because the water pickups would get enough water regardless.

This past Saturday, it appears that I cooked that engine while out tubing with the family. Thing is, I was trying to stay ahead of the thing just like you by reading forums and asking a lot of questions because I've never had a jet boat or ski and know they are different than the average outboard or stern drive, where I have 30+ years experience. I didn't know exactly just how different they are. I had an appointment with a mechanic who was going to check the boat over from a mechanical standpoint with the hopes of discovering any serious issue before a problem. He was late getting back into town and I went to the river with the family and have now had a major problem prior to diagnosing what I had already identified as a potential issue, but had no idea this would be the result.

I was trying to nurse that engine by only throttling down 1/2 way with full throttle on the starboard engine to keep the rpm down to a reasonable range. It didn't work So, find the issue before you go back to the water or you may seriously damage your engine/pump/etc. over something that might have been a $100 fix. I'm looking at possibly $1200-$1500 just to get the engine fixed before the expense of figuring out the pump issue. :rant:

Good luck!

 

[photo4286]

Need more advice

Ok so I got some stuff done, After Cleaning the hell out of it

I pulled both pumps and they didn't look so good. Both impellers were pretty nicked and damaged. Also both the wear rings were pretty carved up, one better than the other. I posted pictures below. How does this happen BTW ??

The Drive shaft protective cover is all chewed up on the right pump. You can actually see some of the pieces mixed up in the pump (seen in pictures). Do you think this will cause any permanent damage that a impeller/wear ring/rebuild won't fix.

I ordered impellers and wear rings for both pumps and I just happened to already ordered two pump rebuild kits for my XP's which I am going to use for these instead. I won't get the impellers/rings till Thursday, but I can start on the rebuild tomorrow.

Is there any special things I should know about the rebuild, Problems? Trouble areas?

Also is there anything specific tools I need to pull the impeller?

Also the people at SBT said that this is called cavitation, would that of affected the top speed being 40 mph in stead of 50 mph? (BTW that speed test was on the flattest water possible) Also once its fixed will it increase the power / takeoff / acceleration?

Compression - I picked up a compression tester at an Auto Zone and I don't think it is working correctly. I pulled one plug and put the spark plug wires on the posts on the ignition coil. The tester only showed 50 PSI on all four cylinders.

This doesn't make sense to me because they are supposed to have 150 PSI and at least the right engine runs pretty damn good. It instant starts and runs good.

Is it possible for an engine to run 40 mph and all four cylinders having only 50 PSI of compression.

 

[photo4286]

More Pictures

Here are some pictures......

 

[photo4286]

and More Pictures

The last four

 

[photo4286]

Well I won't get the parts to rebuild the pumps (new impeller, wear ring, bearings, etc.) till tommorow

But I was wondering if anyone can help me with my other questions??

Is there any special things I should know about the rebuild, Problems? Trouble areas?

Also is there anything specific tools I need to pull the impeller?

The Drive shaft protective cover is all chewed up on the right pump. You can actually see some of the pieces mixed up in the pump (seen in pictures). Do you think this will cause any permanent damage that a impeller/wear ring/rebuild won't fix.

 

[RFoster130]

Just a few quick answers, You need an impeller removal tool. Ebay for 15 or I think sbt even for like 20. Drive shaft boot is no big deal. Most people leave them off when they break. 40 mph top speed may be cavitation problem. This should fix that. IF it runs to 40, i seriously doubt your compression is really 50. Read up more on how to test it correctly. Good luck...I will try to post more later when I get time.

 

[photo4286]

Is there any way to remove the impeller without one, I have the parts on the way and wanted to try and get it out this weekend?

 

[Dr Honda]

WOW.....

OK... I've seen single point damage that was bad (sucking an object into the pump) but that's even damage. That tells me that the last owner just would beach it with the engines running... and probably back off the beach under power.

Seeing that... I would very carefully inspect the cooling system. Flush it... and make sure there are no obstructions in the hoses.


Tools... the only special tool you need is an impeller removal tool. It will drop onto the impeller, and allows you to unthread it from the shaft.


As far as a "Pump Rebuild"... if they bearings are good, and the oil isn't water contaminated... there is no reason to rebuild them. Just replace the wear rings, and impellers.

If the seals and bearings are bad... then you will need the manual. The bearings need pressed into a measured depth, and the proper way. They don't just get pressed into a seat.


The driveshaft protectors.... they are gay. Remove them. They are there to protect the shaft from sucking up a rope, or whatever... but the first time you suck in a rope... they break off, and go into the pump. Also... they are a source of cavitation. Pull them out, and cut off the little part that goes into the hull... and than just stick that back in. I like to mark them, and cut them so they are flush with the tunnel.

Good luck, and let us know how it goes.

 

[Dr Honda]

Is there any way to remove the impeller without one, I have the parts on the way and wanted to try and get it out this weekend?

Only if they are loose... but you would still need the tool to torque down the new impellers.

You can see if your local dealer has one... but expect to pay +$40 for it.

 

[Phildoo]

Definately have to have the impeller removal tool. Maybe we should start a tool and parts swapping thread to help everyone out?
I just bought the impeller tool and don't forded using it again anytime soon.

 

[photo4286]

Ok so if I take off the driveshaft protectors I have to cut off the part that goes into the whole and put that back in.

Is there a way to check the fluid and bearings without taking off the impeller and wear ring?

I have a PDF of the Shop Manual