2001 Sportster lost it's top speed

[F4i]

I bought the boat about three months ago. The dealership said they replaced the wear ring and tuned the carbs. At this point it would top out at about 43mph. The last two weeks I could only get it up to about 37mph on calm water with only two people on the boat. Yesterday she was still running about 37mph top speed with two people on the boat. Then we put four people on and she would only get up to 35mph. About 15 minutes of driving and she started loosing speed. She dropped down to 11mph top speed, the water was calm. When stopping and starting she feels like she has full power, she just won't get over 11mph. Rpm's were running all the way up as if we were doing 40mph. Then we had two people get off and she would get up to 28mph top speed. I tried putting in some new spark plugs, no change. I looked to see if anything got sucked in under the boat. I couldn't see anything. I'm not sure if running a differnt 2 stroke oil could cause this. I've been buying my oil at the Sea Doo dealer up untill last weekend. The Sea Doo dealer was closed and I needed oil. So I stopped at O'Rileys and bought four quarts of 2 stroke oil to fill up my tank. The oil was really cheap (3.99 a quart) but it did say Sea Doo on the back of the bottle. Any ideas?

 

[seadoodude1]

With the engine still reving up good it sounds like something in the jet pump or it's sucking in air and cavitating. Check for debris and wear ring to impeller clearance but it could be sucking in air around drive shaft or ride plate or where pump mounts to hull.

 

[seadoodude1]

Also on the oil, not likely the cause, but if the engine is Mercury use TC-W3 oil, if Rotax use API-TC oil of which Seadoo and Amsoil make.

 

[F4i]

If something sucked in, would I be able to see it by looking? Or would I need to pull it apart? Looking at it I don't see anything but I did pull up on the beach at the local party cove. With all the rain we've had latley there was a bunch of debris in the water.

 

[kustomkarl]

If you getting full revs and it' just had the wear ring replaced, it sounds like you have a stick or something stuck in the impeller. Usually it will have a vibration from the jet pump too. Using a flashlight look in the jet nozzle, from the rear and look closely for something stuck in jet pump. If you do see something, use a long screwdriver to poke it out.

Karl

 

[F4i]

I don't see anything in there.

 

[rookie101]

What does the wear ring and impeller look like? If you beached the boat, or were running in too shallow of water you may have sucked some rocks into the pump in which case you may have destroyed the new wear ring or impeller.

Also what engine does the boat have? You should add it to your profile.

Aaron:cheers:

 

[F4i]

What does the wear ring and impeller look like? If you beached the boat, or were running in too shallow of water you may have sucked some rocks into the pump in which case you may have destroyed the new wear ring or impeller.

Also what engine does the boat have? You should add it to your profile.

Aaron:cheers:

From what I can see everything looks good. I don't think I sucked in any rocks but I'm pretty sure I sucked in some sand and possabily a few small pebbles. Would I see physical damage when looking inside?

I registered on here today off of my iPhone. So I just filled out the basics. When I get home, later today I'll update my profile and post up some pictures.

 

[timmyboy76]

Sportster LE..951

Need to hit up O'Reilery's here..(they bought out Kragen), i'll take a few qts for that price..

If nuth'n in the jet pump/impellor area..need to undo the nozzle cable and reverse bucket cable, then removethe 4-17mm nuts, hold'n pump against the hull, then pull the unit. Only take 10minutes..like what was posted above, think ur wearring and/or impellor is shot...atleast this way, you can actually seethe problem, with pump in hand.

 

[F4i]

Lol, it's semi synthetic it says Sea Doo Bombardier on the back of the bottle. $3.99 beats the $12.50 a quart at the dealer.

Cool I'll pull it apart and check it out this evening. If it's bad will I see physical damage?

 

[timmyboy76]

yup...chunks missing, bend blade/s, more than a 1/2 dime thickness, in clearance of wear ring and impellor blade.(which you can see if you looked into the nozzle area).....:cheers: btw, you by chance remember the name of oil/bottle?

 

[F4i]

Not off hand but I still have the empty bottles at the house. So I'll post it up when I get home this evening.

 

[F4i]

It's called MasterPro the bottle says part no. 80022

 

[F4i]

http://www.oreillyauto.com/site/c/detail/OMP2/80022.oap?keyword=80022

 

[F4i]

The impeller has a few small nicks in it but my concern is it is digging groves into and thru the wear ring.

What's a good impeller to use? Are there any that will help the performance of the boat? Or is there a place that I can buy a full rebuild kit including bearings/shaft for a good price?

 

[F4i]

Thanks everyone for the help. I put the new impeller and wear ring on yesterday. Let the silicone cure for 24 hours dropped her in the water today and she runs like new again.

 

[seadoosnipe]

Bearings?........

The impeller has a few small nicks in it but my concern is it is digging groves into and thru the wear ring.

What's a good impeller to use? Are there any that will help the performance of the boat? Or is there a place that I can buy a full rebuild kit including bearings/shaft for a good price?

What about the bearings, did you change them out? The quote in the thread about digging grooves, ....this could be from bad bearings, especially if the ring was just replaced.

If you did not replace them and they are bad, you'll know after running about the same amount of hours. The speed will start to fall off again.

 

[F4i]

Na, But now you have me wishing I would have. When I ordered the impeller I ask them about a new shaft and bearings. They said that they shouldn't need replacing.
Is there anyway of telling by feel if there bad or going bad? There was about a 1/4 inch of play up and down only untill I put the cone on and then there wasn't any play.