NEED HELP! Stumped..,

[KELLI MILLER]

We just purchased a 1997 Sea Ray Sea Rayder. 120hp Sport Jet. We put it in the water this past weekend and it wouldn't do over 10mph. We bought it knowing it would be a fixer upper, but now we are stumped and finding very few who will work on it. The engine starts right up and it goes into forward and reverse. It pushes out a huge wake, but will not get over 10 and won't plane out. The previous owner said it ran about 30-35 last time he had it out but he was loading it on trailer and bent up the ride plate. Does anyone know if this will cause the problem we are having? Where we can find parts? And anywhere in KY, IN, or TN area that fixes them? We have a Sea Ray dealer in town, but it's too old for them to work on it. We gave $2200 for it. Is it worth fixing or should we sell as is? Any advice is appreciated. Please help!

 

[Boat Crazy]

Not knowing much about them, but sounds like you are getting cavitation which is air enduced into the jets. Could be debris, loose caulking, or bent ride plate, but if both engines are doing the same thing, (assuming it has two)would start with checking for debris or caulking first.

 

[Scottintexas]

if he bent the ride plate down that would certainly hinder your speed and create a large wake (but 10mph is pretty slow),

how about a picture of the bent piece?
does it have a tach? do you know how many rpm's your turning?

 

[KELLI MILLER]

if he bent the ride plate down that would certainly hinder your speed and create a large wake (but 10mph is pretty slow),

how about a picture of the bent piece?
does it have a tach? do you know how many rpm's your turning?

 

[KELLI MILLER]

Tach and speedometer are broken and being fixed by local marine repair. Rpm's are running high based on what we hear. Sounds like a car being revved up in neutral. I don't have a pic of the bent plate, but he said it was bent pretty good. He tried to straighten it out with a sledge hammer. It fit back on there but there's no way it can be a tight seal. Somebody said it could be the pump, but would it push out water if pump is out?

 

[Scottintexas]

the pump is just the cavity the water flows through unless it is bent like the plate it shouldn't be an issue unless it's missing sealant

another thought would be the impeller/s, can you see them either looking up through the bottom or from behind the boat?

What does the output of the jet look like? I know you have a big wake but is there a high pressure stream coming out of the pump when your going 10mph?

 

[KELLI MILLER]

the pump is just the cavity the water flows through unless it is bent like the plate it shouldn't be an issue unless it's missing sealant

another thought would be the impeller/s, can you see them either looking up through the bottom or from behind the boat?

What does the output of the jet look like? I know you have a big wake but is there a high pressure stream coming out of the pump when your going 10mph?

 

[KELLI MILLER]

Impeller doesn't appear to be bent. The wake coming off the back is high pressure and looks like the wake coming off our out jet ski. When we put it in forward it takes right off, but it's just not going fast. Marine repair called to say the engine is doing it's job and has plenty of power. They don't know enough about jet boats to diagnose the problem. We are trying to decide if the ride plate can cause that much of an issue.

 

[itsdgm]

Sounds like cavitation to me. Your description of it being in netural revving but going nowhere is the indicator. I believe that cavitation at take off is usually the impeller or something stuck in the pump. On a Yamaha it could be something as tiny as a toothpick. But take as many pics as you can of the bottom of the boat, pump intake, impeller (front & rear) and the ride plate. It would give us a better idea.

 

[Bruce]

Sounds like cavitation to me as well. We really need to see pictures of the jet and ride plate to understand how it works and possibly see the issue.

 

[Murf'n'surf]

The bent ride plate might actually get it up on plane just like trim tabs would. You must have some sort of pump issue. We need pics of the impellers from both sides and specifically the clearance between the impeller and pump housing.

 

[Gym]

My thoughts also @Murf'n'surf, impeller clearance. I would agree pics would help a lot. @KELLI MILLER have you tried locating a service manual for this?

 

[Gym]

Just for our education here is some info I've found for this boat. This YouTube is the larger engine version but should give a flavor for this boat.

@KELLI MILLER here is a Sea Rayder forum under iBoats.com http://forums.iboats.com/PWC-Forum/Sea-Rayder
Not to steer you away from this forum as we like to learn and help where we can but they may have a better idea as to what you need and where to get it. That being said...Have you checked your thrust diverter at the jet nozzle? Is it all the way up out of the thrust when in forward? If not you could be diverting thrust, killing your speed. Hope you stick around here after checking the other forum.
OK, I think I found a service manual that covers your engine and jet pump. This should help.
http://1manual.com/Mercury manuals/Service Manual PDFs/JetDrive/831996r1/cover.pdf

 

[jcyamaharider]

Having gator boats in my area I know that ride plates are a huge deal on these boats. Small adjustments to the ride plate effect the boat in a major way. They will tweak on them ( 1/16 ) at a time to get the boat to ride the way they want in the water. This ride plate sounds like it is bad and needs replaced. Like everyone said a picture is worth a thousand words.

 

[Bilmon]

If ride plate isn't sealed it will cavitate badly. Sounds like that is exactly what you are getting. Parts are going to be a bitch to find powerhead is based on a Force 4 cylinder outboard.

 

[Bilmon]

Also can find some info in the archives on www.jetboating.net

 

[Cammcrobb]

Could I get some info on the deflector shield? Mine doesn't go up and down when I move it forward to reverse, this is on land, should it?

 

[Beachbummer]

Yes it should!! Very much!!! That would explain your lack of speed too!!

Confirm cable operation. The gate should move with the lever. See if you can push the gate open by hand *Gently*. Cable might be busted.

How easy does the lever move? There should be some friction required. If its super loose, that's another sign the cable is busted.

 

[Cammcrobb]

There is resistance in the throttle, I can't push it up or down by hand, only like 3/4 "

 

[Cammcrobb]

I have a regal jet boat rush xp, 120hp 1995