questions about Used Carbs replacing my old ones

[scooper77515]

My old carbs were shot. I took one apart, and half the bolts, screws, and jets broke or stuck, and the insides were full of sand, oxided aluminum, and rust. one of the mounting tabs was busted, etc.

I doubt I can rebuild them without a LOT of work, so I just bought a set off ebay.

The guy has pictures of the sides taken off. http://cgi.ebay.com/ebaymotors/ws/e...STRK:MEWN:IT&viewitem=&item=270168451513&rd=1

After viewing the pictures, should I go ahead and use my rebuild kits on them now, or wait until next season?

Also, he has the chokes taken out. Should I put mine in these carbs or run them as they are?

 

[seadoosnipe]

Carbs!

Scooper, thanks for letting me help you out again.

The carb pix look great, but looks can be decieving. I use ebay quite a bit and after you look at the feed back and determine the seller is a seller of PWC parts. That will help you determine whether the carbs are going to work with your application. I looked up some info for you on what I read in your profile cause you didn't really state it in your query; your looking for carbs to fit the 1996 XP with the 787 Rotax. If this is correct, your carbs are the Mikuni BN-40 I (diaphragm).
I'd email the seller and ask him if the carbs your wanting to buy are that make of carb. Several carbs on the Rotax engine look the same, but are different. The size bore or the type..........or the size jets. Which jet sizes can be changed according to where you live in reference to altitude.
If you email him and he states that they are but when you get them, find they dont' work because they aren't, then that email will give you what you need to go into arbitration, if necessary. Dealing with ebay myself, and I love to shop there, I've learned to be really cautious.
I hope these carbs work out for you and my advice is more of concern for you to get what you pay for. I hope it all works out for ya!....let me know if I can help again!............:hat:

 

[Captain Rick]

Personally !! Leave the chokes out and put Primer kits in,
do it while you have them out. Much better as there will be no
air restrictions, this from the racing group. I did mine and
I am much happier this way. The pics look good put in good rebuild kits
and jet them for your area. Set the high and low jets and the popoffs, and then have fun
Good Luck

Rick
PS and get rid of that Damn grey stock tubing, its a carb Killer !!

 

[scooper77515]

Thanks for the feedback. From my history of working on cars, my theory is "any working carb (that fits) is better than a non-working carb", and I hope that theory works on PWCs also

These carbs at least look rebuildable. The ones I have are literally falling apart as I try to work on them.

Should I use the jets from my carbs in this one or just keep the ones that are in it? I am not trying to weed out every last horse, just have a fun ski to play with.

Also, what is "priming", or more specifically, I know what it is, but "How do you do it with PWC?"

My rebuild kits are Mikuni brand, since I wanted to be sure they were the correct ones and if I bought another brand, I would have no idea if they fit or not until it was too late.

 

[seadoosnipe]

Primers?

Primers will allow you to pump extra fuel into the throat of the carb for starts rather than using the choke. If you've ever seen the little bulb on a lawn mower that you push 2 to 3 times to get it to start. That's a primer. In my opinion, I'd install the primers if I were looking to build a racer but for just to be out on the water as a regular rider, I don't know that it would serve any purpose. The restriction of the choke plate is minimal.
Your rebuild kit doesn't come with jets? If the carbs are in as bad as shape as you describe, then the jets may be too.

Now I see why in your first post, your ski wasn't running so good. Let us know how you make out!.............:hat:

 

[scooper77515]

I am amazed that it was running AT ALL:agree: Especially running as good as it did once I got it moving.

Actually, the brass jets and rods are the only things that appear ok in my carbs. The aluminum and other parts are all corroded.

I will throw those carbs on and see if it runs, then go from there.

 

[seadoosnipe]

Jets

If your familar about jetting, then you know the sizes are determined by the amount of fuel that will pass through them. If there was abrasive material that got past the filters, then those jets have probably been "wallered" out.

 

[scooper77515]

...and since the jet needles were the only parts that were still polished looking, I will assume they were recently polished by the abrasive material

 

[scooper77515]

What's bad about the gray tubing? Is the clear stuff what I should swap with, or can I go with regular automotive fuel line?

I think I will replace ALL fuel lines and filters while I am doing this...

 

[seadoosnipe]

Gray lines?

I don't know, Captain Rick seems to have a great knowledge of the PWC's in a racers point of view. Sounds like he does a lot of hot roddin on um.....I just ride them. My 787 is ten years old and I still have the original fuel hoses on them. I haven't heard any complaints. Maybe he'll pop back into the forum and explain this to us. I'd love more insight on this.
Regular automotive fuel should be an adequate replacement. It's inexpensive and easily available. :hat:

 

[scooper77515]

I was just going to swap them out because they are likely gummed up from having fuel sit in them for 4-5 years while it wasn't running.

Maybe a carb cleaner additive instead?

 

[seadoosnipe]

Swap?

Swap them out? ....I assume your talking about the fuel lines. Yeah, I'd just swap them out. There is one line between the two carbs that you'll have a little tough time with. Cut a new one about the same measured link of the old one, but if you wait till you put the carbs on, you can kinda bend it in a U and slip it one. Mine had those crimp clamps on all the lines. I got ride of those and put the standard clamps on the fuel hoses.
I use a generic carb cleaner to clean everything on my 787!.........I love the stuff. It knocks off grease and oil and parts that are gummed up and leaves no residue..........
When you rebuild the new carbs, there are some tolerances that you'll need to check.....If you bought carb kits, those tolerances and settings are probably on an instruction page. A lot of the carb stuff is a no brainer, but make sure you read about the check valve and pop off pressures. :hurray:

BTW, I hit the edit button on your last post by accident. I didn't edit anything........

 

[scooper77515]

As long as you are editing for grammar, spelling, or punctuation, and not for content, I don't mind:hat:

 

[scooper77515]

By the way, I am cutting those crimp clamps off. Is there an easier way?

I figured I would just tear them apart and put on regular screw-on clamps when I replace the lines.

 

[seadoosnipe]

Fuel lines!

If your gonna replace the fuel lines, then don't worry about the crimped clamps till you remove them. There really isn't that much tension holding them on. You should be able to grab them by hand and by using brute force, just pull them off. If not, get a knife and cut the hose in the middle till you get them off the engine.
BTW, I don't edit content or grammar........I make many mistakes of my own. The only thing I might edit would be foul language and as many posts as I've read and replied to, that's never happened.

BTW, taking the carbs loose from the rotary plate can be a pain in the rear. Mine were seized with a white corrosion kinda stuff. I think it was from electrolysis........If yours are hard to break loose, try getting some penatrant into the the bolting area of the carbs.

 

[SeaDooNewb]

Scoop, I"m going to chime in since we appear to be in the same boat. Those carbs look great IMO. The ones I got on e-bay were better than mine but not as clean as these pics. They cost me ~$150 for the pair.

RE: tolerances, I donno. I know that the needle valve lever needs to be flush with the body and the sea doo and Mikuni manuals say to check the pop off pressure but in my mind it's not worth messing with that. I'm actually just rebuilding the carbs for my father in law who bought this ski as a package with another one and a trailer and this one didn't run very well (hardly at all) so if I can get it running he'll be happy. I can play with the low and high speed screws to cover up any hesitation that I may get when I put it all back together. Priority #1 is to get it running again. My filters were clogged big time and lots of corrosion inside. I had to easy out many of the screws. It's a good thing I got two extra carbs instead of just one.

Scoop, I'm in Pearland and have some property down in West Columbia and Jones Creek so I go past Angleton fairly often. PM me if you want to compare notes some time.

 

[scooper77515]

Cool. I work in Pearland (actually Manvel) and have been running the ski at Bastrop Bayou at FM 2004 and 523. Close to home, and fresh water.

Your issues and method of acquiring the ski sounds exactly like mine. This was given to my dad who started paying me to do the work. Now I have pretty much "stolen" the ski because he sunk $300 into parts, and I have another $300 or so, and am doing all the labor. He rode it once and didn't really feel comfortable on it, so I just took over:reddevil: