• This site contains eBay affiliate links for which Sea-Doo Forum may be compensated.

dropping a new motor into the GSX

Status
Not open for further replies.
Sorry I missed this... but yes. A new engine, with extra oil in the fuel... you will have smoke. Once in the water, and warm... it will burn the oil more efficiently, and the smoke will be minimal at an idle.

BUT............. just to make sure you didn't pull a "Rampage".... check the cable going from the carb, to the oil pump. At this point, just make sure the arm on the pump is moving with the throttle. Since the arm is spring loaded, it is easy to get it flipped all the way around. If it got flipped, then it's going to smoke like crazy !!!

Once you get the idle set for real. (in the water, and not on a hose) you can adjust the cable on the pump.


Regardless....... smoke is good with a new 2-stoke engine. ;) (bad with a 4-stroke)

checked the cable and all is good. looks like all i have to do now is GO.
 
everything was cool ... including the weather. brrrrrr


sun finally came out and all the boats are ready. i had the seadoo on the back of the truck sunday. when i went to prewarm it in the driveway it wouldn't turn over. i thought the battery was dead. i charged it overnight. it still wouldn't turn over. it would start to then stop as soon as compression started to build. i had my battery checked and after being on the charger all night the guy at the battery store said it was good, but needed a charge. said my charger might be bad. i bought a new charger. charged my battery all night. tried turning it over this morning it cranked a few times and stopped again.

i pulled the plugs and turned it over. THE CYLINDERS ARE FULL OF FUEL. WTF??????????

i knew this would happen. i'm literally crying right now. it's gonna be 90 this week and i just wasted my whole winter. :(


edit: i had my choke wedged open last time i tried to start it. would this have caused my problem? i've flushed the cylinders out and it turns over now, but still won't start. now i think the battery died again. or it loaded up.
 
Last edited by a moderator:
i had it on the hose. i had turned the hose on before starting it. maybe i back filled the cylinders with water?

i'm stumped.

charging a new battery at the moment.

:-/ ...
 
NEVER turn the hose on until after the motor is running.

seems i filled it full of water while trying to start it on a dead battery. didn't take but a minute.


after removing the plugs and flushing the cylinders several times i got all the water out. a big cloud of black smoke and a puddle of oil out the exhaust later ... she's running again.

my wife puts up with me. i need to find a way to thank her.


taking the crownline to the marina tomorrow. hopefully i'll have the seadoo up there by the weekend.
 
UMMMMMMMMmmmmmm..............................................


You've been her long enough to know you don't turn the hose on first. Run the engine a few times to make sure all the water is out of the engine.
 
UMMMMMMMMmmmmmm..............................................


You've been her long enough to know you don't turn the hose on first. Run the engine a few times to make sure all the water is out of the engine.

winter stupid. i'll take the lashings.
 
winter stupid. i'll take the lashings.

OK... here it is.


1.gif
 
OK... here it is.


1.gif



if that's the case ... gonna go turn the hose back on.:thumbsup:








WOOOOO HOOOOOOO, finally made it to the lake. perfect day. weather was pushing 90 and the water was like glass at a brisk 63 degrees.

this watercraft has never performed this well for me. it is snappy like it should have been a long time ago. before the new motor i was always chasing some little problem. broken water regulator spring, grey fuel lines, gunked up raves valves, .... just about the time i thought i had it worked out the motor went. i used to have to "pump the throttle" to get it to catch and pop up while getting squirrelly. now it just goes. no stall, no delay, it's just up and out of the water. it's almost like a "brand new machine". lol :D

i have put 2 hours on it so far. my arms get tired the first few times out. i tried to run it at varying RPM's. never exceeding 6000. only burned half a tank of fuel so i still have a ways to go before it's "broken in". i have a few things of concern that i'll go over briefly.

thanks again to everyone who has helped me. sorry it took so long. we had a really "off" year weather wise.


things that concern me, ...


i have to pump the throttle to get it to start. -
it seems as if the carbs aren't holding fuel pressure. once it does fire up it lags until fuel gets to it fully. i can hold it at full throttle and it sputters and starts after cranking over a couple times. then while continuing to hold it wide open the RPM's slowly increase until it fully loads up. takes a few second. 5 -10 maybe. it's idling at 1540 and does fine once it goes. i can cruise around at idle speed with no problems. once i do give it gas is it very responsive and seems to be fine. no cutting out or sputtering at any speed.

the ignition housing and crankcase are getting pretty warm -
after running for 15 - 20 mins the ignition housing and the crankcase, near the rear of the motor, feel warm. i can hold my hand on them, but if they were any warmer i wouldn't be able to. the top end, as well as all of the exhaust is cold to the touch. pretty much "lake temperature". my pee hole is peeing. when i squeeze the oil bath line on the IN side it moves in the tube on the OUT side so i know my oil bath is good. this may all be normal, just need verification that it's ok to be warm.

vibration at 3500 - 4200 RPMs -

i'm gretting a slight grumbly vibration that starts at around 3500 RPMs. it stops once i get up to 4200, or so. the motor responds smoothly when throttled, but continues to vibrate. it gets a little rhythm going if held at around 3800. i have replaced my wear ring but i didn't rebuild my jet pump. the o-rings and bearings "seemed" ok so i didn't bother changing them out. it almost feels as if it could be coming from there. but then again it almost feels as if it's coming from the front of the motor. when i aligned my motor, using the SBT alignment tool, it was almost perfect. the alignment tool slid in with just the slightest "bump". you could barely even feel the shaft going into the female end. not sure what the runout is on this. i'm guessing mine was within a few thousandths. guessing ...

i'm going to go over everything with wrenches and make sure it's all stayed tight and solid. if i can work out these few small concerns i think all will be well. looks like it's gonna be a great year. :coolgleam:
 
Last edited by a moderator:
i torqued down the front motor mount a 1/4 turn. not sure if it loosened up or was never wrenched down. gonna go ride it for a few hours and then recheck it.

found a few hose clamps on the fuel lines at the carb that took a 1/4 to 1/2 turn as well.

my wife says, "it's a motor, shouldn't it be warm?". yeah, it should. the ignition cover just seems a little "too warm". she's usually right though. ;)

i'll check back in tonight.
 
The vibration could be the loose motor mount... but most seadoo's have mid RPM vibrations.

Yes... it's an engine, and it's going to be hot. If it isn't burning you... it's fine. Also... a fresh engine will run hotter than one that is broken in.

The hard starting is caused by leaky needles, or a crappy after market diaphragm in the carbs. I would check them out.
 
fired right up in the driveway before i left for the lake. once i got there i almost drained the battery trying to start it. after A LOT of smoke and sputtering, it finally slowly started running. after that it would stop and start up if i restarted it immediately. if i stopped long even to have a tasty beverage i would have to pump the throttle to get it going again.


still have some vibration.

after a full hour of riding i could put my hand over the ignition cover, but it was too hot to keep it there.



edit:

saw doc's post after i posted. thanks again. looks like all i have to work out is the fuel issue. otherwise, "i'm stoked". i can so no reason why i'd ever want to get rid of this ride. it's soooooo snappy and light. i can pop it right up into the air off the slightest ripple. big ol' cruiser rolled thru yesterday leaving about a 4 foot deep trough behind it. i launched about 36 feet into the air. :)

my wife's crownline blew the drive line. i'm waiting on parts for it. once i get her back on the water i'll get some action video shot and posted.
 
Last edited by a moderator:
checked my carbs. they were full when i tore them down. i put my old springs back in. just because the new ones looked slightly different, and felt a lot stiffer. the old ones weren't that bad. i can always throw the new ones back in later. the needles are the original ones. those were never changed. it's still "snappy" and runs better then ever.

i checked my plugs and they were pretty dirty, heavily oiled. i think the heavy oil i'm running may be causing them to foul out. when i put clean plugs in she fired right up. i didn't let it sit for any extended period between start ups , while on the water, so i'm not sure if my fuel problem is fixed or not. i sat for a few minutes and she fired right back up.

gonna try to make it back out today. so far i have 5 hours on the new motor. the vibration i was feeling seems to be smoothing out. feels and sounds like nothing more then the exhaust growling at this point.
 
WOW!!!

i can't get over the "snap" she has. i rode this ski for 2 years and always had to "pump the throttle' a little to get her to pop up. not anymore. she'll damn near buck me off if i lean back a little.

the wind was blowing hard yesterday and pushing up a nice swell out in front of the damn. if you time it just right, have your angle correct, and pump the throttle properly you can launch off one wave, leap over the next, and then gently land on the third without the slightest bump. like you never even left the water. there were a couple times i was actually "looking down" at the water.

now all i can wonder is, ... why don't i ever see anyone riding a seadoo like a seadoo is meant to be ridden? i see people on them all day long, zipping from point A to point B at 60+ miles an hour. never once thinking to spin it out or launch it airborne. soooo much fun to be had ...
 
break in period complete. :cool:

runs like a brand new machine. :thumbsup:


it rained this weekend and the forecast calls for rain this week as well. my wife's boat is all ready to take out to shoot some video, 'cept it won't stop raining. :(
 
i am currently rebuilding my787 engine for my gsx and found this thread EXTREMLY helpful. i have one questions tho. why did you need a new engine? my counter balance shaft is shot that is why im rebuilding mine
 
i am currently rebuilding my787 engine for my gsx and found this thread EXTREMLY helpful. i have one questions tho. why did you need a new engine? my counter balance shaft is shot that is why im rebuilding mine


i threw a rod bearing on my crankshaft. i have no idea why.


Does the lower end need to have oil in the crankcase like on a 4 stroke?

yes, i think the exact amount is in this thread somewhere.







my wife has stolen my toy, ... IMG_0125.JPGIMG_0123.JPGIMG_0119.JPGIMG_0106.jpg


i have some video to load soon as well.


:)
 
i have put over 50 hours on my new motor this summer. i am getting a small amount of oil blowing out of the forward rave valve. i just wipe it off after each use. it's not enough to cause me any concern yet. it would be nice if my new motor stayed clean, but whatever.

it seemed to really start running good after about 25 - 30 hours. all the vibrations have smoothed out. it is very snappy as long as i keep fresh plugs in it.

i am pleased with my SBT rebuilt motor. i see no reason why i can't keep this ski forever.
 
Glad you got it running after reading all these posts

Newbie question here - I was looking in my Clymer manual (1988-1996) to verify what they say is the correct oil.
I can't find any mention of the "counterbalance shaft". Is it called by something else too?
I'm looking in the crankshaft section and also in the index.
 
Last edited by a moderator:
Status
Not open for further replies.
Back
Top