How to Rebuild your Carb

[qstorm]

Here is some excellent info on rebuilding your carb. Maybe you can turn this into a sticky.

BTW- I am not the author of this. The origination is from this location http://www.seadooforum.com/showthread.php?t=3495

 

[seadoosnipe]

High speed screw....

qstorm, excellent delivery and pictures on the process of re-building carbs. I'd like to see you edit the post to include citation as to the person(s) or corporation as to who or where this originated, this way, copyright infringement may not occur in the forum. Normally, a company such as Mikuni will not pursue such matters, but if the written words of someone else is personal, they may.

One other thing. The high speed screw doesn't show the plastic cap. What happened to it? Do you remove that yourself? In the manual, the high speed screw is really not adjustable and can't be removed without taking that cap off. The manual recommend you not take that cap off, it's preset at the factory and only gives the user the ability to "fine tune" it by 1/4 turn either way. Playing with the high speed screw is very dangerous to leaning out at high speeds, and it only takes 1/8th of a turn to lean out to cause sever if not permanent engine damage.

So, while I love the effort and all the work involved in what you've presented, you do say you aren't the author, please cite the person or web-site this work came from so I can refer to it for further questions.

Thanks in advance and great job!

 

[qstorm]

Seadoosnipe, I edited the post to indicate where the file came from.
As to your other question. No I didn't remove that screw. Thanks for bringing that up, cause I would have removed mine. :ack:

qstorm, excellent delivery and pictures on the process of re-building carbs. I'd like to see you edit the post to include citation as to the person(s) or corporation as to who or where this originated, this way, copyright infringement may not occur in the forum. Normally, a company such as Mikuni will not pursue such matters, but if the written words of someone else is personal, they may.

One other thing. The high speed screw doesn't show the plastic cap. What happened to it? Do you remove that yourself? In the manual, the high speed screw is really not adjustable and can't be removed without taking that cap off. The manual recommend you not take that cap off, it's preset at the factory and only gives the user the ability to "fine tune" it by 1/4 turn either way. Playing with the high speed screw is very dangerous to leaning out at high speeds, and it only takes 1/8th of a turn to lean out to cause sever if not permanent engine damage.

So, while I love the effort and all the work involved in what you've presented, you do say you aren't the author, please cite the person or web-site this work came from so I can refer to it for further questions.

Thanks in advance and great job!

 

[seadoosnipe]

Your link....

Your link re-directs you back to the original post. But that's o.k., if it originates from this forum and you have just "bumped" it up to the front for all, then you don't need to cite.

Anything from outside the forum should be cited. Unless you take the infomation read and re-write it in your own words.

Thanks.....

I must be gettin old, I don't remember that old post.........:rofl:

 

[JPX]

In-carb fuel filters -

It is incredibly difficult to access the PTO carb's fuel plate without seperating the carbs. In theory, an offset screwdriver could get in there.


But the MAG carb's fuel block can be removed without taking the carbs off.


I wasn't looking to do a full rebuild. But I did want to inspect the in-carb filter. And WOW that thing is small.

And WOW was it full of a bunch of junk. I rinsed it off with soap and water and most of it came off pretty quickly.


Don't get me started on the original gray fuel hosing (the most likely source of the gunk in the filters). I haven't gotten around to doing that particular "must do".:ack:

 

[JPX]

Took apart the second (PTO) carb's internal fuel filter. Yuck. Same junk - maybe even a bit worse than the MAG carb.


I unbolted the carb from the block, but I left the hoses connected (trying to do as little work as possible). The screws for the fuel plate want to strip. So I used a pair of vice grips on the heads to give them the "pop" to break loose. Then they came out easily.


The carb mounting bolts needed a scrubbing with a brass bristle brush to get the corrosion off the last inch of thread.

 

[markrvp]

I'm not bustin' your chops, but if you don't replace those fuel lines now, won't you have to do that again real soon?

The fuel line is cheaper than just one of the carb rebuild kits.

 

[JPX]

Point taken -> http://seadooforum.com/showthread.php?t=4809:agree:

 

[calgary seadooer]

wow you guys are really amazing with the details in the carb rebuilding have a 97 challenger and thinking of doing it myself i just know thats what it is and think it'll make a big difference the guy i bought the boat from didnt do a really good job with matience....the rave valves were horrible and im determined to get this boat running smooth.....have a big problem with the throttle cable now and the forward reverse cable too....boat only goes in forward direct me to a helpful thread on that if its not too much trouble!

 

[dabeetereater]

nice work,
im guessing its the same for a single carb,

i got a 2 skis with single carbs on them,
just got them yesterday and they need carb work/cleaned,

 

[JPX]

im guessing its the same for a single carb,

Half the work

 

[Hokiebob]

Hello, I'm a newbie here. Just got a 97 SPX that has the gray fuel lines and the terrible bog/no speed issue. I removed the carbs today and began disassembling them but I can't find the in-carb filters. I've looked at the fuel inlet on the front (Mag?) carb and also on the other side. Am I missing it or does my setup not have them?

thanks
bob

PS - this forum is awesome folks like me. I'm a fair mechanic but Rotax is new to me.

 

[Hokiebob]

Nevermind-I should have looked at the first attachment--indeed I have them and surely that is the problem---terribly blinded by a tar-like substance. Can these be cleaned or should I replace them.....do they come in the carb kits?

thanks again

 

[JPX]

They can be cleaned - but don't use carb cleaner on the filter as it dissolves the fabric in the filter. Use a toothbrush and q-tip to work the gunk off in hot water with soap.

Some carb kits come with the filters - others do not. This particular kit does http://seadoosource.com/carbpkgs.html

 

[jst4sho]

Used product from Wallyworld called Greased Lightning. Wife had it in the washroom and gave to me after I complained that soap and water was not doing anything for the sticky goo. GL did more in 30 seconds than 90 minutes of my work prior to trying that....jstrsho...ron

 

[seadoosnipe]

Compressed air........

Like JPX says, the carb cleaner should only be used on metal parts. It's a very volatile and powerful cleaner, to dissolve gunk in the ports of the carb. For the filters and other fragile parts, I use brake parts cleaner, it's a nice soluble cleaner, like carb cleaner but not as hot.

For the filter, I found that the compressed cans of air, that I use to clean the dust from my computer, works well in the carb filters too!.....

Carb kits.....there are several places to purchase them. Depending on what your willing to spend. All carb kits come with everything you need to rebuild the carbs, some come with extra stuff that you'll not need, yet, you'll be paying for them.

The carb kits from SBT come with all you'll need to rebuild the carb, including the filters........for $35 bucks.......I've not found a cheaper place yet.

Good luck............:cheers:

 

[robin savell lloyd]

This is a very informed carb rebuild thread and seems to have a good title that should be easly found in a search. thanks to gstorm and jpx this will be a great asset for people searching how to rebuild their carbs. I noticed that seadoosorce is working on a idea that the gray fuel line issue may be a misunderstanding and I am leaning to this idea my self as I have seen many photos with the grey fuel lines but none show that the fuel line to be bad so I am not sure that it is the fuel lines that are cloging the internal filters. This may have been just something thrown out there. If any one has photos that shows a grey fuel line that is bad, gummy or in some other way please share it with us all. Thanks Robin :cheers:

 

[JPX]

If any one has photos that shows a grey fuel line that is bad, gummy or in some other way please share it with us all. Thanks Robin :cheers:

 

[robin savell lloyd]

Jpx when I read the artical from seadoosorce You were the first pearson to come to mind as you have some very good photos online. I notice in photo #1 the iner liner is discolored but to me that is not that bad. Now in the #2 photo I see that the inerliner appears darker and I notice that there is some chiping away a the edge were it was cut. I was not shure if you may have chiped at it to see how bad the material was or if the when it was being cut that the edges chiped away. I allso notice that toward the back of this photo #2 I see something that may be gooey. I realy can not tell as some times photos are decieving. Do not get me wrong you take some very good photos with good clairity maybe you could give a descriptive detail of what we are seeing in the photos of the bad fuel lines. There has been a on going write up on these grey fuel lines and I have noticed that where the fuel line conects to a fiting is where you will normally see some gue or gumy discoloration. What some peaple said they did was cut the end off and reinstall. Last but not least what color was the original inerliner when new. Thanks for all the info:cheers:

 

[battscrew]

Thanks all - this thread helped me clean my carb filters - I am not much of a mechanic but was able to get it done a reassembled - only have done the hose test and revs (just over 3000) up and down well - next week out to the lake - also started to replace the grey hoses (just the carb area for this week).

PS I have 120 hours on my GTX the front carb filter was pretty good, the rear looked a little better than JPX's front carb filter.

My grey hoses have little green film in a couple of spots - I have read that it may be some sort of sealant from the manufacturer?

 

[MontanaXP]

oops..carb cleaner on my filters!

I went through my carbs before I read about not using carb cleaner on the fuel filters...What are the chances that they are now toast? been together for a few days and only ran twice for a short time...

 

[seadoosnipe]

Fibers......

If they didn't melt in your hands when you cleaned them, chances are, your probably o.k.....but, could have also weakened the mesh where it comes together with the framework. So, I'd suggest, removing at least one in the near future to inspect.......:cheers:

 

[scooper77515]

Has anybody used this as their primary instructions for rebuilding their carbs?

I printed it all out in color and plan on using it tomorrow. I just want to make sure that there won't be any surprises, errors, or missed steps...