SJ4 taking on water
- Thread starter segmentlime
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Big Kahuna
Administrator
- Location
- Tuscaloosa, AL
Its not a valve in a normal sense. But the hole does not stop the suction pressure causes bye the pump. But when the motor is turned off, if there was any water left in the bilge line, it could create a siphon back at that split second the motor turned off and start pulling water back into the hull. (Like when you use to steal gas from your sisters car!!!!!!!) The hole causes the suction to loose its pressure and stop sucking water into the hull. I would check the hole again or even order the new section.
- Location
- near beautiful bobcaygeon
yes, will do but I will not be able to do the job until the week of July 15th.
The kit comes with a 500 gpm Rule 25DA pump. I do not have the pump yet so see exactly what might work, but I have some concerns because it is very tight spaces around the bottom of the hull where it might go, On the port (left) side there is the exhaust expansion chamber and on the right the steering cable is routed there. As well, the bottom has large ridges running from bow to stern on either side of the mid-shaft, I am not sure the pump will fit to the bottom around there. At this point I am not sure exactly where it is going to be able to go around the mid-shaft area. I have an air intake kit with the bracket for the ECU and relays that allows for the removal of the stock air intake box. Once that is pulled I will see if any opportunities for placing the bilge pump up there but of course this is not ideal as it is too far forward and not the low point most of the time. The job might even involve doing something creative to reuse the first part of the existing siphon bilge system whereby the pump is modified to go inline with that versus mounted right to bottom of the hull. An issue here is that the siphon bilge hoses are smaller than the 3/4 bilge pump output, and I am not sure about such input restrictions - something allowing more flow might be needed to put the pump inline.
If anyone has already done an electric bilge in SJ4 then any info would really be appreciated.
@eastbay - if you proceed prior please keep posting here.
- Location
- near beautiful bobcaygeon
Yes. I think the hole is meant to serve as you indicate BK. The hole was definitely clear just prior to when i reinstalled the right angle connection, as I had completely removed it and was able to blow air through it. There is so much water in the hull in such a short time, that it seems like it had to be flowing in reverse for nearly the entire time i am riding. The hose cannot be blocked anywhere or the water would not go in or out. In fact when i block the hose at the end that is supposed to go to the reduction nozzle then no water enters, so this is almost certain the route. What I wonder is if that at least at some rpm there can be a positive (not negative) pressure at the opening of the inside of the reduction nozzle and this is just pushing water up and over the siphon?
It is weird that no one else has reported any similar problems.
- Location
- near beautiful bobcaygeon
@Big Kahuna - I don't know that this makes any difference but, would you please tell me exactly how your siphon hose is routed from the transom to the reduction nozzle? Specifically, at the top of the reduction nozzle starboard of center there is another little connection tube sticking up vertical that has nothing attached to it (on mine); when you look towards the transom from the back, does the siphon hose routing go around the port (left) side of that stuck up piece and then connect to reduction nozzle or around the outside of it to the starboard (right) side of the tube?
Also, just to confirm, that connection tube sticking up is not connected to anything on your ski is it? Not sure what this connection is for but it seems maybe it is used when reduction nozzle is used on some other model of ski. Do you know what it is for?
Also, just to confirm, that connection tube sticking up is not connected to anything on your ski is it? Not sure what this connection is for but it seems maybe it is used when reduction nozzle is used on some other model of ski. Do you know what it is for?
i think i saw Takaai mounted in hole he cut into the foam behind the midshaft housing but i cant find the pic now. I will run two when i put them in.
- Location
- near beautiful bobcaygeon
Ok thank you very much. I was thinking the pump could not go there because of the steering cable. It looks like Takaai moved his steering cable so it is not routed through that hole in the white plastic midshaft bracket. I do not think the pump can fit there otherwise. I guess I will have to do the same, and this can only be done from the handlebar end. (lol, too bad I did not know this when I changed to the cable to one with more throw the winter before last! That job was a big pia and not looking forward now to having to do it again).
- Location
- near beautiful bobcaygeon
I installed a bilge pump to the SJ4
Key was cutting out the right foam to allow that the pump could go as low as possible in bilge (note that in the pump location I cut the foam right down to floor), and also some just starboard of the the pump to allow the pump to be a squeezed down into the final location.
Also the lowest position was achieved by routing the pump output nozzle and hose under the midshaft tube, and to exit on port side.
Key was cutting out the right foam to allow that the pump could go as low as possible in bilge (note that in the pump location I cut the foam right down to floor), and also some just starboard of the the pump to allow the pump to be a squeezed down into the final location.
Also the lowest position was achieved by routing the pump output nozzle and hose under the midshaft tube, and to exit on port side.
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Big Kahuna
Administrator
- Location
- Tuscaloosa, AL
You might want to consider re-routing the bilge line, Make it come up high then down to the outlet. I did one on my first SJ and it was way too low, would let water in some. But test out and see if you have any issues.... Looks great.
- Location
- near beautiful bobcaygeon
Yeah, best practice would be to use a longer hose and route it up a bit before exit just as you suggest. That was the hose that came with the bilge pump kit (along with the pump, the handlebar switch, and the electrical connections including fuse and waterproof fuse case). If it seems water is coming in I will buy some longer hose and improve the routing. So far it seems ok.
- Location
- near beautiful bobcaygeon
@Big Kahuna - I decided to try to improve the system by extending the hose and adding a check valve.
The check valve is blue in the picture and I added a small loop of (black)hose before the exit vent. The check valve is at the topmost part of the loop.
Any water that might come in the exit hole while the bilge pump is not running will fill the black tubing only and cannot get past the check valve. When the ski is right side up any water in that black hose will run out due to gravity.
Big Kahuna
Administrator
- Location
- Tuscaloosa, AL
Are you still getting water in the hull?
- Location
- near beautiful bobcaygeon
The stock siphon pump system has been disabled by disconnecting the hose from the reduction nozzle and bunging it. So no unexplained water since then.
If I am in rough conditions like waves or whatnot and the ski goes over on side and I do not get it righted right away then it seems I can get water in bilge. I figure this is coming in through the air vents in front of the hood, maybe even some through the hood vents. This was what motivated me to get the bilge pump.
The bilge pump setup seems to be working fine, and I doubt I will need it much, but like I say I can get water if I am coming off a lot in rough conditions.
I think if I had a do over I would put the exit vent a little higher up the side of the hull. I think it would have been ok as it was but the check valve and higher loop like your suggestion are certain improvements.
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