Carb Confusion

Note: This site contains eBay affiliate links for which SeaDooForum.com may be compensated
Status
Not open for further replies.

mashenden

Active Member
What in the name of everything right am I doing wrong? I am trying to rebuild my carb (single carb on a '95 SP 587). I have the pump side attached and am trying to test the pop off, but can see/hear air leaking out from between the carb body and the pump. In other words its leaking from the area where the pretzel o-ring is located. It seems to be coming out all the way around. Nothing seems overly warped or scored. I have the pretzel ring and the rubber diaphragm damper but no other gaskets in this area. Then on the pulse side of the pump I have a gasket and the mylar pump diaphragm (this area does not seem to leak). Am I missing a gasket?
 
What carb kit are you using? If its not OEM this is your problem. The cheap e bay kits are garbage!!
 
As near as I can tell from the previous post as well as the SBN manual, I have the right parts in the right places. Any suggestions on how to stop the leak?
 
I got mine from SBT. Thought it was OEM. It was not the cheapest out there.

Thats your problem. I have had this happen A LOT and finally decided never again. Some times the old rubber O ring I replaced fixes the problem. If it still looks usable, give it a try. If not get a OEM kit.
 
So I put the old pretzel ring back in and no leaks. Was it a bad assumption to think that the SBT kit was OEM?

Any recommendations on a source for the best price on an OEM Mikuni SBN carb rebuild kit?
 
So I put the old pretzel ring back in and no leaks. Was it a bad assumption to think that the SBT kit was OEM?

Any recommendations on a source for the best price on an OEM Mikuni SBN carb rebuild kit?

Check out OSD Parts or Parker Yamaha. If in Canada, look at Winners Circle.
 
SBT is hit or miss on parts, their carb parts are less than perfect. If you compare a oem and sbt rubber ring you will see the difference.
 
SBT is hit or miss on parts, their carb parts are less than perfect. If you compare a oem and sbt rubber ring you will see the difference.

Apparently a big miss. I am so mad at myself. I made up my mind that I would go all OEM on the carb rebuild based on many posts in this forum, but then somehow ordered a kit that is complete crap. To make matters worse, I then ordered a needle and valve from them. GRRRR...
 
OSD is best on the carb kits. He give just what you need for the your setup. I have used named brand aftermarket kits with good results also the brand was winderosa. They are make here in the USA. No issues with them they are like $25-$30 a carb.
 
OSD is best on the carb kits. He give just what you need for the your setup. I have used named brand aftermarket kits with good results also the brand was winderosa. They are make here in the USA. No issues with them they are like $25-$30 a carb.

I decided to go with OSD this time. It was not cheap but only because I wanted to go with everything. It is unquestionably OEM. I also like the ala carte ordering options.

Given how much the SBT o-ring leaked, I wonder if they will take that garbage back?
 
It looks like things are back on track. I received the OEM rebuild parts and pieces from OSD. After breaking my carb all apart again and reassembling, it now holds 10 PSI for way over 10 minutes. OEM made a huge difference - you could actually hear air leaking out when I had the SBT pretzel o-ring installed.

Now pop-off is about 22, which is right on the money for this carb.

I'll hopefully have it reinstalled and ready to water test this weekend.
 
This weekend was time for the water pressure to meet the water (analogous to "the rubber meets the road"). It was a good time!!

My jet ski now starts each time (one exception to review below), and accelerates without hesitation - very fun.

Going with an OEM rebuild kit allowed me to maintain 10 PSI for 10 minutes, which was something that reared its ugly head after first rebuilding the carb using a non-OEM kit :)banghead:).

Replacing the needle and the seat was most likely the solution for the flooding problem I was having the last time I test rode it. The needle bubbled prior to replacing, but not after. More conclusive is that it now starts up after sitting, instead of flooding :cheers:.

The only things not 100% are 1) that the idle hunts and will eventually cut out if left alone without a blip of gas, and 2) if I hit the gas when trying to start it then it will flood and not start for a bit (this happened more frequently when I had a passenger on the ski with me ??).

I am thinking that the carb is a bit too rich (intentionally) so I plan to adjust the low speed needle in a bit. Plugs look a bit wet too.

Presumably I am on the right track on this.

My main question is whether it is worth fine tuning the carb at this point given I am still running a bit of extra oil in the gas (2 oz added - I am at the tail end of breaking it in) or should I delay fine tuning until after running the gas/oil out and changing the plugs?
 
Last edited by a moderator:
ok, Seadoo is very good with what the settings on the carbs should be. Follow what they say and you will be good. I add a 1/4 richer on the high screw for everything. Want to be safer. Rich is safe. Plugs are cheaper than engines. I would say you just need to turn up the idle a bit for help with your dieing out at idle since you are have to give it a bit of gas to keep it going. You really shouldn't need to give it gas to start again after it is warm or sitting a bit if you have a choke still on it you just need to choke it real quick to start it. If you have a primer system give a few squirts. You can also just drop the passenger and make them get their own ride ;-).
 
The trouble with making them get their own ride is it would be me that would end up working on them :)

I probably did not state it clear enough, but I did adjust it to be a bit rich, intentionally (1/4 from the user manual recommendations), which is how you also do it. According to the sticky on carb adjustments, I may have to lean it out a bit to get the RPMs to stop cycling up and down. But honestly that is not a biggie - I can live with the way it is currently idling.

My main concern is that it occasionally floods when trying to start it , particularly if a user does not know to not hit the gas while cranking (but not like it used to from just sitting).

So, my main question is whether I am wasting my time trying to tune the carb given that my gas is spiked with oil (from the break-in period) and therefore should wait until after I run that out and swap out the plugs?
 
... So, my main question is whether I am wasting my time trying to tune the carb given that my gas is spiked with oil (from the break-in period) and therefore should wait until after I run that out and swap out the plugs?

Does anyone have an answer to this?
 
You should be able to get it close even with the oil.
If it is running good now and plug color looks good I would just wait until you switch to straight gas.
 
You should be able to get it close even with the oil.
If it is running good now and plug color looks good I would just wait until you switch to straight gas.

Again, it is occasionally flooding, which is going to kill my starter if I don't get it right. Once up to operating temp, it floods when starting if the rider gives it even a bit of gas, or interestingly if I have a 2nd person on it. Plugs look wet.

This makes it a PITA to stop and pick up riders. It is better than it used to be where it would flood every time it sat after being run.

I'll lean it out a bit by adjusting the Low Speed in some. It was out about 1/4 turn more than the manual states. I just didn't want to waste my time doing that if the extra oil was probably the cause - it sounds like extra oil in the gas should not stop me from getting it running better.
 
I would go back to the stock setting and see if it improves. 1/4 turn richer than stock especially with the added oil could be your issue.
Is it actually flooding like a stuck needle or loading up like it it just too rich?
 
I would go back to the stock setting and see if it improves. 1/4 turn richer than stock especially with the added oil could be your issue.
Is it actually flooding like a stuck needle or loading up like it it just too rich?

More like its too rich, not like a stuck needle. No noticeable effect when it is running, though.

Last year it flooded while sitting. I am convinced that the new needle/seat fixed that.
 
Damn this is frustrating. I confirmed the oil was leaking from the check valve by connecting it to the battery vent hose (that's not connected to the battery since it's an AGM). When I checked it today I had some oil down the outside of the hull, which was better than in the hull, but more importantly confirmed the leak. A new valve is installed with about 6" of extra line so it is slightly uphill making it real hard for oil to leak out.

The pisser is that I did nothing to the carb since last weekend, but now it jumps up on a plane immediately when going WOT, goes about 100' feet and then completely loses power. Sometimes it stays sputtering, sometimes dies completely... WTF??

It still starts well, idles reasonably well (still a bit up and down) but not a deal killer, and jumps up on a plane with no hesitation. But then just loses everything.

Any advice on where to start would be extremely appreciated. My fun to anger ratio is off balance big time!!
 
Oh, one more thing - I changed the plugs yesterday and took it for a test run. No change - may have gotten a bit worse.

I tested it WOT several times, and it was the same - started up, jumped up on a plane, and the bogged down after 100'.

Then the last time I tried to start it, the motor stopped turning over (without sounding sluggish first). Presumably I wore the battery down, but I am worried it is something worse. While I have not tried real hard, with the plugs out, I noticed the PTO would not budge. If something has locked up, this ski is going to become an artificial reef.
 
Last edited by a moderator:
Status
Not open for further replies.
Back
Top