When I was a kid my dad had 2 aluminum tanks built for our Glastron 19 ft boat. I remember the fuel filters went to the pits within the first week and needed to be replaced twice more real quick. No matter how well the tanks were cleaned ahead of time, shavings still remained and moved through the system. It was an outboard, so the filters were see through. Hopefully it is indeed low fuel as you think, but if not, check for fuel flow. A brand new system could be prone to the effects brand new debris.
-
This site contains eBay affiliate links for which Sea-Doo Forum may be compensated.
Challenger 4tec Upgrade
- Thread starter IDoSeaDoo
- Start date
- Status
IDoSeaDoo
Well-Known Member
I know there were some shavings from where I had to make the last mod on the tank to make the intake manifold clear, but after my first two trips, I drained all the gas via the siphon tube. I sucked it through a 2stroke seadoo fuel separator and was surprised by how little came out of it. This engine doesn't have a fuel filter, it's designed into the fuel pressure regulator. Inside there are a bunch of paper folds. Can't imagine those getting clogged to the point where it would make a difference, but who knows
snikwad003
Well-Known Member
How old is that paper filter
snikwad003
Well-Known Member
Is the fpr built into the fuel rail? If you could get a wideband o2 sensor in the exhaust it would help you know how she is running
IDoSeaDoo
Well-Known Member
The fpr sits on top of the fuel tank. It's a bitch to get to since I have to remove the seats. I'm going to do the lazy thing and hope it's just low on fuel. I think I sucked in a bunch of bubbles into the line, and caused it to stutter. When I would drop rpm it went back to smooth idle. She doesn't sound any different, and after a bit of idle went back to screaming at wot
snikwad003
Well-Known Member
That thing is impressive
snikwad003
Well-Known Member
Tdi powa! I want to put one in my mk2 but its a GLi and i dont know if i can do that my self. The running lights skip all that but you could add a 4th to pull power from the fused source for stop/turn to take the load off the jettas stock circuit
IDoSeaDoo
Well-Known Member
Went out today with my family for a bit of cruising. They haven't been on the boat yet, so I picked today to give them a ride. I had at least half a tank and it started doing that thing where it cuts the RPMs. It's the damnest thing. On Saturday, I invited two friends, and them and the wife rode in it all day, starting with a full tank, and NO PROBLEMS. But when the tank gets to about half way or less, it does this weird engine bog. The rpms fall and fluctuate at around 4k or so. Opening the throttle makes them fall more, so I think it's starving for fuel. Again, if I slow down to idle, it idles fine (well, not perfect, the idle does fluctuate by about 100 rpm but it always does that). After a bit of idling, I can open it back up to WOT and it seems to run fine. I was cruising about 6k rpm when it happened the first time. Then after idling, I was going about 5600-6k and it happened again. Both times seemed to happen after a turn.
Just after it happened, I made sure it wasn't my engine crank case pressure creeping up again. I quickly reached in and cracked open the oil dip stick. No tell-tale hiss, so I think I'm good there. No oil seeping from around the valve cover or anything. I think what's happening is that when I turn, all the fuel is escaping to one side of the tank. I believe I made the holes in the baffles too large. Since it happens at around half tank, the fuel fills up that half of the tank and starves the pump. I believe it introduces bubbles into the line and drops the fuel pressure until they're cleared out. So I'm wondering what my options are in this case. The original tank had no baffles, and this problem never seemed to arise no matter how hard I turned it, and no matter how much fuel was in there. The old engine had carbs though, and now it's fuel injected with an in-tank pump.
Just after it happened, I made sure it wasn't my engine crank case pressure creeping up again. I quickly reached in and cracked open the oil dip stick. No tell-tale hiss, so I think I'm good there. No oil seeping from around the valve cover or anything. I think what's happening is that when I turn, all the fuel is escaping to one side of the tank. I believe I made the holes in the baffles too large. Since it happens at around half tank, the fuel fills up that half of the tank and starves the pump. I believe it introduces bubbles into the line and drops the fuel pressure until they're cleared out. So I'm wondering what my options are in this case. The original tank had no baffles, and this problem never seemed to arise no matter how hard I turned it, and no matter how much fuel was in there. The old engine had carbs though, and now it's fuel injected with an in-tank pump.
IDoSeaDoo
Well-Known Member
I wish I could do that. Unfortunately, regulations forbid a marine fuel tank to have any fittings anywhere but the top of a marine fuel tank. I suppose I could have another tank that has another fuel pump in it, but it would also necessitate a float switch or some other device to transfer fuel from one tank to the other.
I suppose the hole could be at the top with a tube to the bottom that would work juat as well.
No need for a float switch, add a return line to the small tank and have a pump running all the time the engine is running, that will fill the little tank which should never then run try and any excess will just rerun to the tank.
Or what about making your own baffle for the tank ( if there is enough room) a cylinder around the fuel pick up with holes around the outside big enough to let the fuel in but restricting the fuel enough to keep the pickup wet. Large holes at the top so it can fill quick when the tank is above say 1/4 of a tank but little holes at the bottom restricting the fuel on the way out but allowing fuel in if your extremely low.
No need for a float switch, add a return line to the small tank and have a pump running all the time the engine is running, that will fill the little tank which should never then run try and any excess will just rerun to the tank.
Or what about making your own baffle for the tank ( if there is enough room) a cylinder around the fuel pick up with holes around the outside big enough to let the fuel in but restricting the fuel enough to keep the pickup wet. Large holes at the top so it can fill quick when the tank is above say 1/4 of a tank but little holes at the bottom restricting the fuel on the way out but allowing fuel in if your extremely low.
IDoSeaDoo
Well-Known Member
I have baffles in it already, but the holes in the baffle corners must be too large. The pump already sort of has a baffle around it. Last I checked, it was full of fuel and drained slowly when the pump was lifted out. I think I should probably open the tank back up...
IDoSeaDoo
Well-Known Member
On pg16 there a bunch of pics of the fuel tank and baffles. I wish I listened to my dad when he told me the holes were too big. Live and learn, right?
I might try cutting 4 triangles out of aluminum and creating a clip- in sort of attachment for them. Maybe use another piece of metal and pop rivets to pinch it to the baffle and reduce the hole there...
I might try cutting 4 triangles out of aluminum and creating a clip- in sort of attachment for them. Maybe use another piece of metal and pop rivets to pinch it to the baffle and reduce the hole there...
What about using some of the fuel tank foam?
I have no idea what it costs but I know race cars use it instead of baffles, assuming it's not quick and easy to take the top off the tank you could maybe force the foam into the centre though the gauge hole and that may provide enough resistance.
Andy
I have no idea what it costs but I know race cars use it instead of baffles, assuming it's not quick and easy to take the top off the tank you could maybe force the foam into the centre though the gauge hole and that may provide enough resistance.
Andy
snikwad003
Well-Known Member
Weld a sump for the pickup to sit in
snikwad003
Well-Known Member
I thought you already pulled the tank and cut the top off again. You could try a round baffle around the pick up along with the clip in triangles
snikwad003
Well-Known Member
Could be, from random fotos on the webz it looks like it has horizontal slots in the bottom where it slurps it up. Does yer pickup reach the bottom of your custom tank
IDoSeaDoo
Well-Known Member
Well, I still haven't pulled the fuel pump to dig around down there and fix the baffle problem. My old buddy from my Middle and High school days came down to visit, so the boat was being fully utilized this weekend. We went out on Th and found that the Audio battery was completely discharged. On account of the fact that this guy comes down only once a year or two, I threw caution to the wind and connected the charging system to the dead audio circuit. The next day, the boat alerted me to a low voltage condition. I found a 30A fuse blown. I put the spare in, and that one blew within an hour. I put yet another 30A fuse in, and then the boat started complaining of a HIGH voltage condition. At that point, I disconnected the rectifier altogether. I pronounce it DEAD. Good thing they're only $35 for a new one. I bought two. I would like to install it somewhere where it can get some cooling. I realize the original location placed it in the intake tunnel, where the incoming fresh air cools it off. Well, my intake sucks air from the heat soaked engine bay. Not sure if there are any advantages to moving hot air over it... or is there? I could install a computer CPU fan on it... Anyway, I need to find the reason my audio battery died. I think there's either a short, or that battery has bit the dust.
I did get some progress on the gauge pod. That duct tape job is shamefully ugly and is the last thing keeping this boat from being picture-worthy.
I'm currently building an extended visor for it and will install led lights to illuminate it at night
I did get some progress on the gauge pod. That duct tape job is shamefully ugly and is the last thing keeping this boat from being picture-worthy.
I'm currently building an extended visor for it and will install led lights to illuminate it at night
- Status
Similar threads
