1994 650 XP carb rebuild

[dan68]

Hi guys I'm new to the form but have been reading a lot lately a lot of great information here. I have a 1994 seadoo 650 XP that idles but backfires through the carburetor when you try to give it some gas. I was told it needs a carb rebuild kit or timing was off. It would rev up fine before I stored it for the winter but never did ride it as I purchased it late in the season. My question is anyone know a good source I could send them to and am I on the right track? Thank you.
Dan

 

[rvaughn704]

I think you are on the right track.
But I would just rebuild the carbs myself. It is not that hard and youtube has plenty of how to videos on it.

 

[nckb]

If you do need to rebuild the carb(s), I agree with rvaughn. It's not that hard. Six months ago, I had never touched a seadoo. Once I got over my fear of making a mistake, I successfully rebuilt the carbs on both of mine with the info on this forum plus a few youtube videos. The first one took me about 8 hours. The second and third one took about 3 hours total.

I saved several hundred dollars in the process, and have since spent all my savings on gas and oil.

 

[dan68]

Thanks guys I did watch a few utube vids and will look at some more in the next couple days. I haven't seen anyone using a pop off gauge. Someone at one point told me you need one to set what ever. Is this true? It does look pretty basic. Also is the rotary valve on this supposed to be set at 147 and is it possible for that to cause the backfire through the carbs or most like let a running lean issue due to a plugged jet? Thank you again.
Dan

 

[LouDoo]

If your ski still has the grey tempo fuel lines, replace them and clean the fuel delivery system before you clean the carbs. Also, I'm not saying you don't need to clean the carbs. but the backfiring sounds more like a timing issue to me, once you remove the carbs. would be a good time to check the timing.

Lou

 

[dan68]

Lines have been replaced I see they are black gates hoses. I have a 1992 580 that I put a motor in and set the rotary valve timing, is this one the same as in 147 with the bottom of the mag port at 360? Thank you.
Dan

 

[dan68]

So here's where I'm at now. Pulled carbs. Can't seem to get the local dealer return my calls to purchase a rebuild kit so I took them apart. In my eyes everything looks ok. Maybe you can't tell by looking but all the rubber gaskets and diaphragms seem fine. Little filters look good and nothing trapped in them. Sprayed carb cleaner in all holes and blew with compressed air. Was able to get all the jets out but one pilot. As long as I was that far I checked the rotary valve. It was 147 degrees and 360 at the bottom of the mag port. Put it back together and did the same thing. I'm lost.
Dan

 

[rvaughn704]

Okay
As far as Dealer not returning calls. Just go to ebay to order your Rebuild Kits. I get 99% of my parts right off ebay and never have to leave the house. Besides a Dealer will over charge you.

Now for the timing issue:
I looked in my Seadoo Shop Manual. For 1994 XP Engine type 657 which is a 650cc which makes the Model # of that engine 5854 the timing is as follows.

mm=2.59 in=0.102 degrees=19-21
All of these are " Before Top Dead Center "

Now I have never set the timing on one my Seadoo's and I am not sure how. Hopefully somebody else on here can shed some light on that part for you.

 

[Matt Braley]

You have to pull the flywheel to set the timing and there are marks to line that up but if it's never been apart then that won't be the problem.

Your 94XP has a 657X engine in it. It's not a 650 or a 657 so be sure to make a note of that. Many parts will be the same(like the carb kit you need) but some are not.

Come to think of it the carb kits may be different. The X model probably has the "I" body style like the 717.

 

[dan68]

You have to pull the flywheel to set the timing and there are marks to line that up but if it's never been apart then that won't be the problem.

Your 94XP has a 657X engine in it. It's not a 650 or a 657 so be sure to make a note of that. Many parts will be the same(like the carb kit you need) but some are not.

Come to think of it the carb kits may be different. The X model probably has the "I" body style like the 717.

Ok thank you. So looking on eBay what carb kit would I be searching for?

 

[dan68]

Want to be sure I get the right one, any body?

 

[Mickirig1]

Search OBS Sea Doo parts. The first thing that comes up are Carb kits. He will answer the phone for questions.

 

[dan68]

Thank you!
Dan