After selling my last 2005 GTX that was broken, I figured I would give this one a go as well. I really want to fix this one though, and I don't have a lot of money in this one so far. I dont have pictures yet, but the gelcoat is in need of a good cleaning, needs new seat covers, and a few other things. As far as how it runs mechanically, I don't know. The circuit board is supposedly bad, and the engine runs apparently. I havent looked at this thing in much detail at all, but I got the ski and a single trailer for $200. The main thing i want to ask is: "Where do I start?" First thing im going to do is clean it, and then try to start it. After that, what does everyone think is a good idea to do?
I just bought a 1991 Seadoo Bombardier GT
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- BiRkS_
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I've got a 91 GT, so any questions, ask away. To shed some light, this ski does not have a circuit board per say. It is a CDI ignition. No MPEM, nothing tricky. No grey fuel lines, no complex engines with no room to get to, except the battery. God I hate that battery location. As soon as you replace it, you'll know! But as said above, check the compression, then spark, then fuel. There are no "grounding posts" on this ski. Simply push the start button WITHOUT the lanyard attached. The lanyard only kills the ignition system when removed.
Ours has been in the family since '94 and it was a rental since new. Its been beaten and abused all its life, pulled tubes, wakeboards, crazy rides (sometimes have to show the city folks with new skis how its done...) Only thing we've ever done to that ski is new batteries (3-4 year life, starter brushes, jet pump oil, plugs, oil, and upgraded fuel filter. 150 psi across the board this summer. Keep the oil tank topped off with good quality oil (BRP mineral oil in bulk was a wonderful thing) And this ski will last you forever. If I had to guess the number of hours on ours, I would say close to 400 hours if not more.
Ours has been in the family since '94 and it was a rental since new. Its been beaten and abused all its life, pulled tubes, wakeboards, crazy rides (sometimes have to show the city folks with new skis how its done...) Only thing we've ever done to that ski is new batteries (3-4 year life, starter brushes, jet pump oil, plugs, oil, and upgraded fuel filter. 150 psi across the board this summer. Keep the oil tank topped off with good quality oil (BRP mineral oil in bulk was a wonderful thing) And this ski will last you forever. If I had to guess the number of hours on ours, I would say close to 400 hours if not more.
Crofoot50
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The older skis are the way to go.... They run forever when taken care of. Maybe not as fast but alot of fun to ride.
RodInEscondido
Well-Known Member
Having a small fleet of these older skis that I am reworking, the fuel system beginning to end is a consistent source of problems, even without the grey fuel lines and pretty much dependent on how long the ski has been sitting unused.
unless you can verify the age, get rid of the old gas
A valuable indicator I have found is to disconnect the fuel line from the input of the primary fuel filter/water separator, connect a length of clear 1/4 inch line and start a siphon into a container under the ski. You should have good flow while selecting normal and reserve and have no bubbles in the fuel flow. If the ski is on a stand or if otherwise possible, shake it around a bit to check if you pick up crap in the fuel flow or the color of the fuel changes ... you may need to clean out the tank.
I have consistently seen the pickup lines into the fuel tank leaking, broken off or the filter at the end fallen off or clogged on these older skis.
Add an additional fuel filter just before the carb, standard see-thru automotive filter seems to work just fine.
Good luck and have fun with the project.
Rod
unless you can verify the age, get rid of the old gas
A valuable indicator I have found is to disconnect the fuel line from the input of the primary fuel filter/water separator, connect a length of clear 1/4 inch line and start a siphon into a container under the ski. You should have good flow while selecting normal and reserve and have no bubbles in the fuel flow. If the ski is on a stand or if otherwise possible, shake it around a bit to check if you pick up crap in the fuel flow or the color of the fuel changes ... you may need to clean out the tank.
I have consistently seen the pickup lines into the fuel tank leaking, broken off or the filter at the end fallen off or clogged on these older skis.
Add an additional fuel filter just before the carb, standard see-thru automotive filter seems to work just fine.
Good luck and have fun with the project.
Rod
Hi everyone. I apologize for the severe delay in replying to my own thread. My grandfather passed away recently and I just moved back from my summer job. I got compression numbers, and they were above 135psi. They were closer to 140. I also have spark, and the engine turns over fine. I am not getting fuel to the carbs, but I have done a lot of work since then. My fuel lines in the gas tank were completely gone. They had frayed apart and just rotted away in the tank. I figured I would take them out and replace them, new gas and everything. I tried that and then i figured out that i still wasnt getting gas to the carbs. Either my lines are clogged with gunk or my fuel pump is trashed. Anyway, Fast forward to now and I have the carbs off of the jetski on the table. I took the rotary valve cover (correct name?) off with the carbs like the service manual suggested. The plate on the carb side is scratched pretty badly, but I dont know what all that affects. Now, where do I start on a carb rebuild? I took the pulse cover off to look, and it had a clear plastic diaphragm looking thing that was pretty nasty and discolored. I reassembled so it wouldnt get ruined if its terribly expensive. A good guide would be great, but i've only found guides for the new mikuni carbs so far. I also want to blow out the fuel lines with compressed air if that wont hurt anything, and replace the lines that are cracked or otherwise ruined. Now, what to try next?
I always loved working the older skis, there just wasn't as much there to fail. Some of the older ones had a different fuel pump setup that wasn't integrated into the carb, but if my memory serves me right, 91 was the cut off for the integrated pump/carb with the Super BN. In any case, you need to get fuel all the way to the ports for it to run. A worn RV setup can make it hard to start, but it should still do it even if worn.
pulse line needs to be operational and the pump needs to respond to that pulse line.
if you squirt a little fuel directly in the open carb and get it to kick, you know that there is a fuel delivery issue and frankly, if you have spark and compression, you have 2/3's of the formula. A full rebuild with pump is surely in order. I would be all over that. The fuel selector also needs to be serviced with the rest of the system if you didn't catch that already.
So many problems come down to fuel delivery on these things and so much can get damaged as a result of poor delivery.
You said there was a scratch on the plate, if that is the rotary valve you are talking about, it should be replaced. Pics would be great, but I would bet that you just aren't getting enough fuel.
pulse line needs to be operational and the pump needs to respond to that pulse line.
if you squirt a little fuel directly in the open carb and get it to kick, you know that there is a fuel delivery issue and frankly, if you have spark and compression, you have 2/3's of the formula. A full rebuild with pump is surely in order. I would be all over that. The fuel selector also needs to be serviced with the rest of the system if you didn't catch that already.
So many problems come down to fuel delivery on these things and so much can get damaged as a result of poor delivery.
You said there was a scratch on the plate, if that is the rotary valve you are talking about, it should be replaced. Pics would be great, but I would bet that you just aren't getting enough fuel.
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The carbs arent much different than the later ones if it has the plastic piece you speak of. The pump mechanism does not come with a standard rebuild kit either. They are really very simple, you just need to make sure you get it torn down fully, cleaned well and just replace everything. You will find little plastic flaps and diaphragm parts in the rebuild kit.
Crofoot50
New Member
Squirt some PREMIX fuel in that old beast and see if she fires up . Do what the guys are telling you to the fuel system . ALL THE ADVICE THEY GAVE YOU IS SPOT ON.
I got the rebuild kits from a local boat supply store, and ill tear down the carbs, clean, and rebuild tomorrow. Crofoot, do you mean put straight gasoline into the carbs, and dont mix it just to see if it will start? I'm sure that would be easier to ignite, for obvious reasons. Also, can I just premix my gas and oil and put that in the tank instead of using the oil tank? I dont know why, but it just seems like something else to go wrong. I see downsides to this though, like not being able to fill the tank from a pull up gas station easily. Anyway, I guess ill just go ahead and make sure my oil pump system is working as well. I need to pick up some 1/4" clear fuel line on the way home tomorrow, and I should be good to fix the fuel system. Ill service the fuel valve as well. Thank you all so much for the help. I greatly appreciate it.
I actually posted to squirt some fuel in there also, by rights it should be mixed because it isnt being metered with the oil. Not that a wee bit of straight fuel will hurt anything, but it should be mixed, that is what the engine is designed for.
Since you are already building your carbs, you should wait until after that, you may not need to squirt anything.
Sent from my Samsung Galaxy S4
RodInEscondido
Well-Known Member
Forgot to mention earlier:
If you do not know what oil was used, clean out that system and use proper oil.
All of the oil, fuel, pulse lines should be considered suspect ... insure no leakage. On all the older SeaDoos I have been working on I have found the pulse line connection under the intake to be loose and probably leaking; this is what drives the fuel pump so leaks are ungood.
I recommend using pre-mixed gas for the first running so you can see if bubbles appear/disappear in the lines from the oil pump to the intake manifold ... will smoke a bunch, but just tell the complainers what you paid for the ski. As part of the inspection/cleaning of the oil system you should replace the small oil lines from the oil pump to the intake manifold: 3/32 tygon found at all lawn mower shops ... instructions in the service manual are clear for bleeding/checking the oil system.
I am not sure on the 91, but on earlier skis the filters in the gas tank have a check ball, evidently to prevent fuel flow back into the tank and allowing quicker starting so applying compressed air to the other end may only have the effect of blowing the filter off the line into the fuel tank.
Keep on truckin' and have fun.
Rod
If you do not know what oil was used, clean out that system and use proper oil.
All of the oil, fuel, pulse lines should be considered suspect ... insure no leakage. On all the older SeaDoos I have been working on I have found the pulse line connection under the intake to be loose and probably leaking; this is what drives the fuel pump so leaks are ungood.
I recommend using pre-mixed gas for the first running so you can see if bubbles appear/disappear in the lines from the oil pump to the intake manifold ... will smoke a bunch, but just tell the complainers what you paid for the ski. As part of the inspection/cleaning of the oil system you should replace the small oil lines from the oil pump to the intake manifold: 3/32 tygon found at all lawn mower shops ... instructions in the service manual are clear for bleeding/checking the oil system.
I am not sure on the 91, but on earlier skis the filters in the gas tank have a check ball, evidently to prevent fuel flow back into the tank and allowing quicker starting so applying compressed air to the other end may only have the effect of blowing the filter off the line into the fuel tank.
Keep on truckin' and have fun.
Rod
I'm on my phone, so forgive me in advance. I put premixed gas in the tank after a thorough cleaning. I didn't get all of the gunk out of the tank, but I got most of it out using small gravel and a high strength degreaser. The fuel filters on the ends of the lines were shot, they need to be replaced. Anyway, it runs. It smokes a ton, as I figured it would, but at least I know it runs. I'll check on the oil pump later. I pinched the lines, but not very well. It doesn't really matter though, the oil tank is dry. The lines look okay on the fuel system. I think they were replaced not too long ago. The oil lines probably need replacing. I know the small lines on the bottom of the intake are gone. They fell off when I removed it getting the carbs off. I didn't replace them yet because it was on the oil system that I wasn't using.
The engine revs pretty high. I'm guessing somewhere just shy of 3k, but I honestly don't know. I think I read that anything between 2 and 3k was fine for out of water. In water is much less (around 1.5k?) right? Also, I hit the throttle and it sounds like it hits a rev limiter, but again, I'm not sure. Is there a rev limiter on these things? Thank you all so very much for the help. I'll make sure the oil pump works after a bit, but for now I KNOW the gas and oil are getting mixed.
The engine revs pretty high. I'm guessing somewhere just shy of 3k, but I honestly don't know. I think I read that anything between 2 and 3k was fine for out of water. In water is much less (around 1.5k?) right? Also, I hit the throttle and it sounds like it hits a rev limiter, but again, I'm not sure. Is there a rev limiter on these things? Thank you all so very much for the help. I'll make sure the oil pump works after a bit, but for now I KNOW the gas and oil are getting mixed.
RodInEscondido
Well-Known Member
Before you run it any more ...
There are 3 oil lines to the oil tank; one goes from the bottom of the oil tank to the oil pump, one goes from the bottom of the oil tank to the connection on the block under the intake/carb/rv, one goes from the connection on the block above the intake/carb/rv to the top of the oil tank. The second 2 lines are for supplying lubrication to the internal mechanism driving the RV ... critical that these be connected and oil in the tank or some other method of supplying oil to the gears. I do not know how much effect it will have, but by having the small oil lines from the pump to the intake manifold broken off and not sealed off will allow an air leak into the intake resulting in a lean condition which is definitely not good.
Rod
Thanks Rod. I really didn't want to trust that oil pump. Its just one more thing to fail on a ski that is older than I am, but I am in agreement with you about getting lubrication to the rv, but id still rather premix. All of my lines are connected except the tiny lines on the bottom of the intake. I didn't think about the air leak at the small oil inlets causing a lean mix, but you're right, that isn't good either. When I was running it, it got much smoother and idles well. I have another "problem" that I may have solved already. The ski seems to redline around what I guess is 3000 rpm. (Ive been choking it down a bit to get a reasonable idle speed, but when I don't, it revs up pretty high.) The electrical box was open when I got the ski, so that was a red flag, but I knew what i was getting more or less. I read earlier that there is a rev limiter under an aluminum plate in there that can fail and cause the rev limiter to engage early. I read that disconnecting it will verify the problem, but i will have to choke out the ski, and i cant use the stop button. Ill try that at some point if you all think its necessary. I still haven't gotten it in the water. I need to get it registered again, and get my PWC license, as well as make sure it hasnt been titled before / get it titled. (No worries, i bought the ski from family, so I know where to find the previous owner, and the guy who owned it before him is local.) Thanks again for the continued support! I'd be lost without you all!
EDIT: OldSchool: Sorry for missing your post a while back, but the scratched plate I was talking about wasnt on the rv, it was on the intake side of the rotary valve. It was scratched, and I have pics of some of the stuff I did. Ill have to upload them at some point. Im not sure if this needs to be replaced, but if it does, i will probably end up taking the intake off again to put those tiny oil lines on and possibly service the oil pump.
EDIT: OldSchool: Sorry for missing your post a while back, but the scratched plate I was talking about wasnt on the rv, it was on the intake side of the rotary valve. It was scratched, and I have pics of some of the stuff I did. Ill have to upload them at some point. Im not sure if this needs to be replaced, but if it does, i will probably end up taking the intake off again to put those tiny oil lines on and possibly service the oil pump.
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Sportster-2001-951C-Stock
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This ski is older than you? OMG, I love this, this is great news! 
Take good care of that thing, I love those older skis!
Take good care of that thing, I love those older skis!Sportster-2001-951C-Stock
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You can do anything you want as long as the engine gets the oil it needs. You can even run with oil in the fuel until you're confident the oil pump system is working correctly. The rotary valve gears inside the intake need lubrication too, so you can't get rid of the oil tank completely.
I like having the oil pump system but make sure it's working properly, and replace those old oil lines (3/32ID tygon tubing I think), they shouldn't have air bubbles in them, that can block oil flow. Whatever you do, make sure it's getting oil and the oiling system is working properly it should keep working well with just a little maintenance help and it's worth keeping IMO, and you can't get rid of it completely anyway.
That's what I'm going to do. I have close to $400 in this ski. I might as well make sure the oil pump is working. It may work as it is now, I just don't know. Ill work on replacing all the hoses, and then test to make sure its getting oil. Ill read the service manual for all the info I need. Should I run premix in the tank while testing the oil pump? This ski is a little over a year older than I am, and it looks pretty old. I'm definitely going to get some sandpaper and some rubbing compound on this thing and make it shine again. I think it will clean up nicely.
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