1998 sea rayder f16 xr throttle problem

[brandon t]

hi everyone so im new to this forum and jet boats, i recently purchased a 1998 sea rayder f16 xr with the 175hp mercury engine, i took the boat out a few times and had no problem at all worked perfect, 2 weeks ago i took it out rode it for about 2 hours then when boat was mid throttle (forward) it felt like it was misfiring but full throttle seemed to work fine, kinda scared about it turning off took it back hooked up and left, last weekend tried to start it up and very rough starting (kept turning on staying on for a few seconds/minutes then turning off) after warming up a bit finally stayed on but when i tried to reverse the boat would go forwards also when put throttle forward it would also go forward with very limited power not sure were to begin to try to fix been searching online but cannot find anywhere to start, checked the jet plate and it looks flush any other suggestions would be greatly appreciated thanks!

 

[tdonoughue]

Doesn't sound like a jet issue; sounds like an engine issue. Unfortunately, I don't know much about your type of boat. I would probably start by pulling the plugs and looking at them. Any discoloration or goopiness? Then I would check a) the fuel (dump in some Seafoam or Stabil 360), b) the fuel system (carburetor/injectors) and c) fuel pump (if any).

 

[brandon t]

So you think one of those options could make reverse go forward?

 

[tdonoughue]

Possible, depending on how reverse is implemented on your boat. The engine may not have been producing enough thrust backward, but just pulling in enough to move you forward. I have heard of stranger things. Could be all wrong there, but if you were feeling misfiring, I would start with that issue...

 

[brandon t]

Awesome thank you for your help any other info would be greatly appreciated !

 

[tdonoughue]

...like from someone who actually knows this boat or engine!

 

[brandon t]

Lol any help is good help

 

[Ronnie]

My first jet boat (not a PWC) was a Euroline Cyclone with the same motor and pump as your Rayder. When my boat started doing what you described regarding the hard starting/rough running, I ended up having all three carbs rebuilt for around $750 over 15 years ago. In doing so the Mercury certified tech found that all of the needles in the carbs were deteriorating, like they we delaminating or losing layers of metal. He had never seen that before and sent needles to Mercury for analysis, don't know the outcome but the boat ran great after having its carbs rebuilt.

Regarding the throttle issues, check to see that the little knob, if any, on the throttle mount is depressed. As I recall raising the knob will disengage the reverse gate function so you can rev the engine without putting the boat into forward or reverse. Pressing the key in as you turn it is supposed to activate the choke function.

Good luck with the Rayder.

 

[Bilmon]

Sounds like you have a couple things going on. First, the reverse, when in forward the bucket should be all the way up in neutral it should be about half way over the nozzle and in reverse all the way down. Check to see if that's happening and as @Ronnie says above the little knob on the throttle will allow you to advance the throttle part way in neutral, if that is stuck it could be the problem or a cable could have broken or disconnected. The low speed problem could be the stator, it's under the fly wheel and has coils in it. There are 2 low speed and 2 high speed. The low speed supplies voltage up to 2500 rpm and the high speed take it from there. There are also magnets on the flywheel that are known to come off but I would think that would show up at all rpm. Welcome to the world of older boats, it will either drive you nuts or make you go broke, maybe both here's a link to a service manual http://www.boatinfo.no/lib/mercury/manuals/175xr_sportjet.html#/0

 

[Moose]

I had a 98 sea searayder that did the same thing. After a $2000 donation to a mechanic and still having a problem I traded it in on a yamaha. I suspected it was moisture and degraded electrical insulation but never found the problem. Curious did you find the problem?

 

[RedBarron55]

First thing is to check the compression to verify that it is OK.
You could try turning the flywheel by hand and feeling the same resistance on each cylinder.
After that you can check the plugs firing on each cylinder by clamping the pickup over each plug in turn.
Then check the fuel pressure going to the carbs for about 6 psi (I think).
After verifying compression spark and fuel you can start checking the other things in detail.
A logical progression in troubleshooting will pay dividends.
A separate issue on forward/backward just look at the bucket, with the lower edge at the center of the jet in neutral, all the way down in reverse and full up in forward.
If you have all of those things the question might be how much run time and is it possible that you have bad reeds?
First check the first things Compression, spark and fuel.

You might also want to check for water in the ful as well.
Water won;t make it run backwards, but it will make it run poorly.
I have a 90 Sport Jet in my Hobie Jet Fisherman and have been through many issues, but not on the six cylinder engine and know little if anything about the care and feeding of that motor

 

[sunriseflames]

First thing is to check the compression to verify that it is OK.
You could try turning the flywheel by hand and feeling the same resistance on each cylinder.
After that you can check the plugs firing on each cylinder by clamping the pickup over each plug in turn.
Then check the fuel pressure going to the carbs for about 6 psi (I think).
After verifying compression spark and fuel you can start checking the other things in detail.
A logical progression in troubleshooting will pay dividends.
A separate issue on forward/backward just look at the bucket, with the lower edge at the center of the jet in neutral, all the way down in reverse and full up in forward.
If you have all of those things the question might be how much run time and is it possible that you have bad reeds?
First check the first things Compression, spark and fuel.

You might also want to check for water in the ful as well.
Water won;t make it run backwards, but it will make it run poorly.
I have a 90 Sport Jet in my Hobie Jet Fisherman and have been through many issues, but not on the six cylinder engine and know little if anything about the care and feeding of that motor

I have a Sea Rayder f14 with 90 sport jet, it's not running at full capacity. Changed plugs and ran sea foam and carb cleaner, still only goes about 30mph. Does it need carbs rebuilt?

 

[RedBarron55]

What RPM is it turning? High RPM 50 - 5500 RPM or hitting whatevert he rev limiter is would indicate a worn wear ring / impeller.
Low RPM would indicate low horsepower.
Check on the Chrysler /Force I boat forum for help.
First decide where your problem is.
It could also be a heavy. waterlogged boat.

 

[tdonoughue]

Not very familiar with that boat, but given the year, I would suspect it is a 2 cycle, right? Mix oil in the gas? If so, I know many will swear by a carb rebuild on those. Very simple engines, but they can get gummy with time in the carbs and throws all the mixes off.