95 speedster one engine won't go over 3000 rpm's ?

[dpod14]

Hi everyone, just bought my first boat, a 95 speedster. The problem is one engine seems to run fine, the other doesn't it just won't rev over 3000 rpm. When I apply throttle , it gets up to 3000 rpm then the rest of the stroke of the throttle up to full power produces no further rev. I would think that full throttle, but only 3000 rpm's eventually would flood the cylinders with fuel and foul the plugs and it would run terrible but this isn't happening, so could some safety mechanism to prevent engine damage be kicking in that won't allow full throtle to deliver full fuel. basically limiting fuel to prevent damage ? there are no warning beepers or rough idling or anything I can Put my finger on. could some type of exhaust or cooling water blockage be the problem ? If anyone has any ideas please let me know. Thanks

 

[voodoo]

With any of the 90's 2stroke family inspect every part of the fuel system to be sure a steady flow is available without any air leaking in, a compression test is really the first point of testing lo power, once you know you have 135 or higher then the fuel system is the next area to reasearch, read as much as you do not want to spend - the search tool near the top is a useful tool, spend an hour or so to make sure the fuel filters in the carbs are clear and the filter is not jammed with steel gas can trash or other swarf that blocks the flow.

 

[dpod14]

Thanks for the info Voodoo, I checked compression today and it is at 132 give or take a lb. on each cylinder (I haven't checked compression on the other engine yet, but it seems to run fine) so I'm thinking it is something else. boat sat for three years and the previous owner had just went through the carbs and put fresh plugs in to get it to start and I opened the fuel strainer and the screen is clear. I'll put in the water tomorrow and try running it with partial to full choke, if it runs good this way I would think it is sucking air from somewhere else. Is this a good way to check for air leaking in ? what else would I look for when checking the "complete" fuel system ?

 

[Bills86e]

Each of your 657x engines have separators. Dumping out & examining the bowl contents is a normal pre-ride check. I suggest you do a quick clean and replace needles & seats of the dual carbs on that engine. You will need to invest in a pop-off tester if DYI-ing Seadoos. Bill

 

[seadooya]

pull the carbs, clean them internally, replace the grey fuel lines, and you'll be good, as long as yuo dont replace/lose the spring inside each carb, where the needle/seat assy is..

 

[voodoo]

The popoff tester is the best way to locate leaks, a common one forgotten is the fuel control switch that has 2 rubber rings inside, if you are not sure how to rebuild it a new one is about 25bux, the tiny carb screens are the last place to save your carbs themselves from drinking the trash that is common in marine environment fuel, if you have grey fuel lines this get blocked really bad and leanout problems become big dollar signs as the pistons melt at high rpm.

 

[dpod14]

I just got back from the lake and must restate the problem, it seems I wasn't correct when I said it runsfine up to 3000 rpm. Today it sputtered and cughed at the carb around 1500 rpm when trying to accelerate but still wouldn't get above 3000 rpm (other engine still running fine), give it any choke and it tried to die out so I don't think it has an air leak. anyway it looks like I'm going to have to pull the carbs and look for some crap in them, i have fooled around with small engine carbs a bit but not these type so where can I find a blow up picture and idle screw starting point setting info ? what is a popoff tester and what about the two orings in the fuel switch ? where is it located ?

 

[seadooya]

once carb/s are re-installed, fire that motor up, and remember wherethe idle was located. It should idle at 3k on the traielr, if not, reach down and turn clockwise til you reach the 3k

Have yuo done compression test on the troubled motor?

 

[dpod14]

the only grey fuel line I see is a short piece about 3 inch that goes from one carb to the other all other fuel lines ar black. are you saying to replace this line becuase the inner lining is known to colapse ?

 

[dpod14]

compression is at 132 psi give or take a pound on each cylinder

 

[Dr Honda]

It almost sounds electrical.

OK... this is going to sound like a pain in the butt... but, take the carbs off the engine that is running good, and put them on the bad engine. If it runs good after that... then it's carbs. If it doesn't run good... it's electrical.


You don't have to put the bad carbs on the good engine... but you will need to give it a run in the water to find out if it's working. (pinch off the cooling line to the engine that won't be running so you don't fill it with water)

Normally when I see this issue, I tell people to check the neutral switch... but I think your boat only has one for both engines. I could be wrong though, since I don't have a wiring schematic for a 95.

 

[munnideo1970]

low compression on #2 cyl

Hi, I need some advice on a compression reading I have a 2002 sea doo GTI LE cyl #1 reads 145psi cyl #2 reads 90psi I don't think this is normal, can someone advice me what to do thanks.

 

[shakedown]

Your right Dr Honda, it has one neutral switch for both engines. As well as switching the carbs like Dr Honda says, and if that does not work, switch the fuel send and return lines. That will tell you if it's the carbs, fuel system, or to start looking someplace else like electrical. Having 2 motors you can even switch the electrical systems from one engine to the other( but you have to switch ALL wires, even the starter (+ & -) wires. It's a big pain but at least you can ruel out problem areas by process of elimination.

 

[Dr Honda]

Hi, I need some advice on a compression reading I have a 2002 sea doo GTI LE cyl #1 reads 145psi cyl #2 reads 90psi I don't think this is normal, can someone advice me what to do thanks.

Don't high-jack a thread. And since you started a new post... just wait for someone to answer. (FYI, I already did)

 

[tonyk345]

It almost sounds electrical.

OK... this is going to sound like a pain in the butt... but, take the carbs off the engine that is running good, and put them on the bad engine. If it runs good after that... then it's carbs. If it doesn't run good... it's electrical.


You don't have to put the bad carbs on the good engine... but you will need to give it a run in the water to find out if it's working. (pinch off the cooling line to the engine that won't be running so you don't fill it with water)

Starting up and old thread here but I have the same problem as the original poster. Though when I swapped carbs it does the same problem and my compression is at 125 in both cylinders.

Any advice?