Superjet bog

[jbabb]

Got the speedwerx pipe on and the recommended jetting from LPW. It is currently set up with a 117.5 L, 150 H, 2.5 N/S, and 95g spring. I take it out to start to try and tune the thing and get pretty close I think. It still has a little lean bog off the bottom end but it picks it up quick. The problem I am having is after about 10-15min. of riding and it running good, I get this real bad bog. You can hold the throttle wide open and it just bogs the entire time and won't clear out. If you take it back to the trailer and let it sit for a minute or two, it will have cleared out and run good again. Is this an extreme "too lean" condition? Should I go to a 120 L jet or am I shooting in the total wrong direction here? Motor is stock other than the pipe, which from what little I have gotten to ride it, am amazed by.

 

[Waternut]

Sounds like it's overheating and the electrics are limitng power to the ski. Are you still running stock electrics?

 

[jbabb]

It still has stock electrics and also has dual cooling. The head is still stock but there is a brass fitting coming out the front and going to a pisser. I don't know how it could be overheating? Any suggestions?

 

[Waternut]

Well with dual cooling, the odds of both lines getting clogged is rare but if one can clog, the other can clog too. Try unhooking the heat sensor in the head. If the engine still bogs with the temp sensor zip tied somewhere cool, you'll know it's something else. Just be sure to monitor your engine temp or you could be in a world of hurt if the problem really is temp related.

 

[jbabb]

Now I am lost. I don't know anything about the heat sensor other than it is there. How do I go about unhooking it? What am I looking for? Could my cooling lines be run wrong? I have both going in the exhaust manifold, then, one coming off the back of the head to the bottom of the pipe and the other coming off the head going overboard. Should I have one going into the head and the other into the pipe?
I know the lines aren't clogged because water comes out of both pissers on the side. They are also new lines that I ran when I put the pipe on.

 

[Waternut]

The wire going into the head is held in with a couple bolts. Just remove the bolts and pull it out. Your coolings lines sound fine provided they are attached to the stator and not the reduction nozzle.

 

[jbabb]

Went out and looked at the ski. I don't have a heat sensor on the head. Apparently someone before me took it out because I think I see where it is supposed to go. Also there are two wire, red and black, that are cut at the top of the electric box. The only wires I have on my head are the grounds to the bilge pumps. So that raises the question, what else could it be? Is there another sensor somewhere? I don't think this is a jetting issue because it would be constant if it was. This is a problem that is intermitent. I know that pisser that comes off the pipe doesn't have as much water coming out as the one coming of the head. I just figured that was because most of it went to the stinger. I am at a loss here and getting frustrated.

 

[Waternut]

I'm not that familiar with stock exhausts but I highly recommend you disconnect and blow compressed air backwards through all the cooling lines...especially the ones in the hull. Troubleshooting involves doing things that may or may not be the right answer...you're going to have do things that probably won't do anything to narrow down the possibilities. Otherwise, it's not troubleshooting, it's just the solution.

 

[jbabb]

Ok, blew compressed air through all cooling lines, not clogged anywhere. I have no heat sensor so even if it is overheating it wouldn't bog til it seizes, correct? I don't mind trouble shooting and doing the work, I just don't know where to turn to next. I am gonna try to put my hand over the top of the carb next time it does this to see if it is just a really lean jetting but I really don't think this is it. Especially since it runs so good between times that it bogs.

 

[jbabb]

Did find that the exhaust gasket is leaking a little water, a drop or two, on the bottom side of the riva manifold. If it leaks water I guess it could be leaking exhaust. Could this contribute to the problem? Just taking a stab in the dark here.

 

[Waternut]

Yes if the exhaust gasket is blown, you will experience heat problems. Especially if it's coming from a water jacket. You may also be flooding the engine bay with exhaust too but I would think you would've noticed that unless you just went in and let it sit for 10-15 minutes before messing with it.

 

[jbabb]

Anyone know of a good way to get that one bolt tight on the bottom of the red riva manifold? Can you cut a wrench a special way or something?