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Ok, quick and short..
96 717cc engine Single Super BN stock carb that came with GTI, engine has been rebuilt, new sleeves, new pistons. I forgot to send the head and valve cover out with engine, so I installed this at my shop. Squish gap is a little large.. at 2.0mm. All new fuel lines. (just got a call wont run in on position now, only reserve??!!??) New rotary cover from SBT. orig N&S in carb but passed all test, looks good. push and pull.. carb has been rebuilt with kit I got from local parts place.
history of motor... was on an SBT rebuild for 6 years (great rebuild guys) and she went last year. Was going to just do an upper end rebuild, but bore had to be opened up to 83.5mm, So New sleeves were installed with this current rebuild.
Got back the engine back, installed, fired right up.. no hesitation on land with starting.. set pop off to 36, and low speed at 1.25 and high at 0. Brought to water, started.. but would not move, fell on face. You would have to pull the choke to get her to move. Mind you air box and seat are off to tune. went back to shop, notice the clear film on pump side had kink. replaced with good one from original carb set to get by. set pop off back to 36.. still ran like poo. Went back to shop. Set pop off to 30, ran a bit better. had a low end stumble, but it was a small GeeeeeRRRR and go. I did set the arm to valve body hight. so I went back to shop, set pop off to 29, then 28, then 27, ran about the same through out. decided to put seat and air box on to let my buddy run the boat with the rest of the pre-mix, and then tune... stumble got worse. Again, This was also with pre-mix for brake in. I thought it may effect the bottom end a bit..
Break in is over... going to get her back to tune it, and fix it. i guess she falls flat on her face till she gets going.. but half throttle is full throttle.. no change between half throttle to full.. But, when she gets to full, she goes like a bat out of hell.. just a wicked bottom end stumble.
I'm really getting confused. The rebuild kit i got may have sucked.. So at this point, with the engine the way it is, what would you do? Does squish effect the low end like this? or running like this? could this be a bad N&S combo? I was going to buy another full rebuild kit, and N&S combo that SBT would suggest to get this done and over with.
I'm trying to help a friend, and this boat has gotten the best of me. I've set my rotary valve as accurate as I could.. compression i think was 135-140 on both. My spark plugs were a cardboard brown on the electrode.. and little black on outer ring... also little white from water that got sucked in i think. ( do have photos) Buddy took to water to put around and work pre-mix through.. and the exhaust boot between the cone shaped pipe, and the bottom of the exhaust down pipe if you will.. (its 8 or nice inches wide, and 4-5 inches wide..supposed to keep both pipes close, yeah that one..i guess the clamp let go, so I replaced, been fine)
This boat has fried me. and i'm getting to the point that I am going to be done with Sea-doo.. I don't want this to happen. This boat has gotten the best of me.. Also me installing the head, and valve cover for this rebuild may have effected things? if squish gap is that important to bottom end (i thought just starting)
Again, tips, suggestions, little love for a Sea-Doo? I've followed some tips from SBT, and other places.. and I am at this point. I'd be happy to take some help on this project if your in the western Mass area.. Again... I've played with many models, and this one boat has just really tossed me.. all that can go wrong, went.. The person I used to rebuild my motor, not SBT ( my Stupid *** mistake) has horrid communication issues, and has been a HUGE burdon. lost my motor, delayed me, forgot to do a check in of parts (head confusion) said it was done an built but waiting on gaskets, then called three days later saying it needed sleeves..(yeah, it was done, but waiting on gaskets, yet three days later it had to be sleeved? really?) Please..take my advise, only use SBT for your rebuilds. It is the other well known company for PWC engines. Ah Ha... get it.. All I can say, USE SBT, NOT PWC.. If you been around the block, you know what i'm trying to say.
I do want to extend a HUGE thanks to SBT for a ton of great parts, and many questions answered. I've used a bad company in the past... It's been a breath of fresh air with SBT, and i'm glad I found you guys... Now... Could you help me get this thing running.. and lets show up the other crap company. Ha ha ha.. It seems like every day I place another order for parts, parts at a great price, and in stock at SBT... funny, As I check my messages, I see I have another customer who needs some 717 parts for his Jet boat... SBT, Hear I come!
Again, sorry for the rant... this is a vent/ cry for help.
96 717cc engine Single Super BN stock carb that came with GTI, engine has been rebuilt, new sleeves, new pistons. I forgot to send the head and valve cover out with engine, so I installed this at my shop. Squish gap is a little large.. at 2.0mm. All new fuel lines. (just got a call wont run in on position now, only reserve??!!??) New rotary cover from SBT. orig N&S in carb but passed all test, looks good. push and pull.. carb has been rebuilt with kit I got from local parts place.
history of motor... was on an SBT rebuild for 6 years (great rebuild guys) and she went last year. Was going to just do an upper end rebuild, but bore had to be opened up to 83.5mm, So New sleeves were installed with this current rebuild.
Got back the engine back, installed, fired right up.. no hesitation on land with starting.. set pop off to 36, and low speed at 1.25 and high at 0. Brought to water, started.. but would not move, fell on face. You would have to pull the choke to get her to move. Mind you air box and seat are off to tune. went back to shop, notice the clear film on pump side had kink. replaced with good one from original carb set to get by. set pop off back to 36.. still ran like poo. Went back to shop. Set pop off to 30, ran a bit better. had a low end stumble, but it was a small GeeeeeRRRR and go. I did set the arm to valve body hight. so I went back to shop, set pop off to 29, then 28, then 27, ran about the same through out. decided to put seat and air box on to let my buddy run the boat with the rest of the pre-mix, and then tune... stumble got worse. Again, This was also with pre-mix for brake in. I thought it may effect the bottom end a bit..
Break in is over... going to get her back to tune it, and fix it. i guess she falls flat on her face till she gets going.. but half throttle is full throttle.. no change between half throttle to full.. But, when she gets to full, she goes like a bat out of hell.. just a wicked bottom end stumble.
I'm really getting confused. The rebuild kit i got may have sucked.. So at this point, with the engine the way it is, what would you do? Does squish effect the low end like this? or running like this? could this be a bad N&S combo? I was going to buy another full rebuild kit, and N&S combo that SBT would suggest to get this done and over with.
I'm trying to help a friend, and this boat has gotten the best of me. I've set my rotary valve as accurate as I could.. compression i think was 135-140 on both. My spark plugs were a cardboard brown on the electrode.. and little black on outer ring... also little white from water that got sucked in i think. ( do have photos) Buddy took to water to put around and work pre-mix through.. and the exhaust boot between the cone shaped pipe, and the bottom of the exhaust down pipe if you will.. (its 8 or nice inches wide, and 4-5 inches wide..supposed to keep both pipes close, yeah that one..i guess the clamp let go, so I replaced, been fine)
This boat has fried me. and i'm getting to the point that I am going to be done with Sea-doo.. I don't want this to happen. This boat has gotten the best of me.. Also me installing the head, and valve cover for this rebuild may have effected things? if squish gap is that important to bottom end (i thought just starting)
Again, tips, suggestions, little love for a Sea-Doo? I've followed some tips from SBT, and other places.. and I am at this point. I'd be happy to take some help on this project if your in the western Mass area.. Again... I've played with many models, and this one boat has just really tossed me.. all that can go wrong, went.. The person I used to rebuild my motor, not SBT ( my Stupid *** mistake) has horrid communication issues, and has been a HUGE burdon. lost my motor, delayed me, forgot to do a check in of parts (head confusion) said it was done an built but waiting on gaskets, then called three days later saying it needed sleeves..(yeah, it was done, but waiting on gaskets, yet three days later it had to be sleeved? really?) Please..take my advise, only use SBT for your rebuilds. It is the other well known company for PWC engines. Ah Ha... get it.. All I can say, USE SBT, NOT PWC.. If you been around the block, you know what i'm trying to say.
I do want to extend a HUGE thanks to SBT for a ton of great parts, and many questions answered. I've used a bad company in the past... It's been a breath of fresh air with SBT, and i'm glad I found you guys... Now... Could you help me get this thing running.. and lets show up the other crap company. Ha ha ha.. It seems like every day I place another order for parts, parts at a great price, and in stock at SBT... funny, As I check my messages, I see I have another customer who needs some 717 parts for his Jet boat... SBT, Hear I come!
Again, sorry for the rant... this is a vent/ cry for help.
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