96 xp bog

[Austrian Rotax]

hello everyone, I finally got some time on my hands to fix this issue, so I most likely it is a lean problem as the ski can launch from zero to WOT without any bog 95% of the time and once it gets to WOT RPMs then it will only hold those RPMs for like 8s and then the RPMs start droping by a few thousand, The Tempo fuel lines were all changed by the PO and I dont know what carb work was done as I didnt ask unfortunately. Only thing ive been doing is running a 45:1 premix with the oil pump to help stop the engine from burning up if its lean. I know the fuel is critical to cooling the pistons so I dont hold WOT long and once symtom comes up, I let off throttle to idle, the last compression check I did was last month and it was at 136-140. any ideas would be appreciated and also the ski is hard to start cold im not sure why. Once it is warmed up for a min it will start up instantly once warm.

The possible issues I think it could be are
-lean carb issue?
-RV clearance but I think this is very unlikely and rare, The PO used tc-w3 oil I think though, it was blue.
-water regulator?


Things I have done so far:

-inspected fuel filter bowl under hood clean
-changed spark plugs
-fresh fuel
-the Crank seals dont leak at all so I hope no vacuum leak

I just hope someone can pointme in a direction they think is most likely the problem according to the symtoms?


Thanks for any help and sorry for the long write up.

 

[Mickirig1]

History of the Ski? New to you or had it a while? Just started bogging? Hours on it? Clean interior carb filters? Engine Compression readings?
Check the gasket on water separator / fuel filter.

 

[Austrian Rotax]

I bought it 2 months ago and have been driving it ever since with a bog, but I have refrained from any throttle over half throttle as it runs great as long as im not going WOT. also ive only driven it for max 3 hours since ive owned it because of work . it has had bog for as long as ive owned it. I have no idea how many hors are on it, PO claimed it was rebuilt last year. . . . as they all say. I checked the gasket already and it looked good to me and I put a tiny bit of oil on the gasket to help it seal. engine comp 136-140 last month, ive only driven it for like 2 hours since the last reading so im sure its the same still.

Thanks.

 

[Mickirig1]

Very Smart of you to run premix to protect the engine. I would guess your sucking air somewhere in the fuel system. One thing you need to buy is a pressure tester. ODS Sea doo parts has one for $25. You need a bicycle pump to supply air pressure. Then you need line pinchers or small vice grip pliers.
I would start checking sections of your fuel lines for leaks. Clamp off a section and use 4 pounds of pressure to check. It should hold for minutes. It all checks out it may be time to rebuild the carb or check it's components. Did you pull the internal carb filter? It may be packed with stuff. All the instructions for fuel system repairs and testing are on this site. Don't give up we will help you! Fuel problems are I think, the number one problem with 2 stroke Ski's. There is nothing like getting your Ski FIXED, warm and going to WOT and it GOES! I WIN!

 

[Mickirig1]

You need to buy tools too. Metric hex 3/8 drive and angle drive wrenches. And off size, 8mm socket.
The air box and carb need these size drives and sockets. Put all the removed bolts in a baggie. Spread a cloth under the engine to catch dropped stuff. Read Read Read on carbs and fuel systems. The answer is here, you just need to find it.

 

[LouDoo]

From what you're saying it sounds that you are running lean. It sounds like since the grey tempo fuel lines have been replaced, the previous owner had started the job of cleaning the fuel delivery system but never completed it. Clean or replace the fuel selector valve, personally I have not had much luck cleaning so for $25.00 I would just replace the fuel selector valve.

The other problem area is the carburetors. You need to remove the carbs., clean the passages and possibly rebuild the carbs., also be sure to clean the carb. filters, they are a plastic mesh so use a water based solution to clean them, I use SuperClean, the rest of the carbs. can be cleaned with an aerosol carb. cleaner.

Here's a thread on the subject:

http://www.seadooforum.com/showthre...el-Delivery-Problems-low-revs-bogging-surging

This needs to be done now, running premix is adding additional lubrication, but is doing nothing for the lean condition.

Lou

 

[Austrian Rotax]

ok im going to try cleaning carbs first, ive done it a few times on my dirt bikes and ive read about cleaning the carbs all over this forum and on youtube.

Just one question, can I use a pop-off tester to pressurize my fuel system to 5 psi, also from what I read in the manuel it seems there procedure tests all the fuel lines to make sure there is no vacuum leak? Also doesnt the pop-off tester from sea doo come with a hand pump? And since I have no bog from 0-full throttle 95% of the time then I dont have to worry about pop-off testing my needle and seat or diaphragn? I dont have a pop-off tester so I hope I can get away with that.

Also if I check my internal carb filters and if they are clean then is it worth going through the other side of carb?

Thanks

Sry if some of these questions are stupid im just not sure

 

[Austrian Rotax]

hi guys just a quick update I got the airbox and flame arrestor off, and I took the pulse line cover off the carb while the carb was still mounted to the ski and removed the internal filter and the gaskets and diaqharms the filter in the bottom part is partially clogged but nothing signifigant here are some decent pics and on the inside of carb just below the carb filter I hope someone can identify what im looking at, it looks dirty.

Also the black gasket there looks OK to me but im not sure.

Thanks for the help.

 

[Sportster-2001-951C-Stock]

I bet your carbs "bypass ports" are clogged or partially clogged with gum. Try shooting brake cleaner or carb cleaner through the low speed jet to clear them. Careful when using these in the wrong place, carb cleaner will eat some plastic and especially that thimble filter, I expect.

Also be sure there are no air leaks in the fuel lines, although that usually is really noticeable at all speeds of operation. The fuel/water separator o-ring gasket is especially famous for allowing air into the fuel system once it's old and/or torn. You can perform a low pressure fuel line pressure test to locate leaks, a few psi of air is enough and too much pressure can cause damage.

Some older Seadoos used a rubber pickup tube in the fuel tank that's been known to rot off and allow air to enter into the fuel system, a full tank of fuel runs great in that case.

Tough working on a carb still attached to the engine!

 

[Mickirig1]

www.seadooforum.com/showthread.php?...Tricks-and-traps...Carb- Rebuilding
The dirty round thing is one of the check valves. You need to clean the carb real good and rebuild. You got junk and gunk it that puppy!
The sticky above on carb adjustments has a great amount of infomation. Read all you can on rebuilding. If you can wrench you can do it! Ask questions on anything you need too. No one will talk down to you or make fun of you. We all been there Brother! Ask away!

 

[Mickirig1]

http://www.seadooforum.com/showthread.php?72980-Tricks-and-traps-to-the-Mikuni-Carb-Rebuilding
Here is right link.

 

[Austrian Rotax]

thanks for all the help, but for now I really just want to try cleaning it really well, warm days here in Canada are becoming scarce very quickly so if I order a rebuild kit shipping may be a week or more. The carb that I took the pulse line cover and check valve housing off was MAG carb, im thinking the pto carb may be worse since that is the cylinder with a bit lower compression, I will have to take carbs off for that it seems. hopefully I can get to the pto carb by thursday and take pics going to be busy untill then unfortunately but ill have all thursday off to see whats going on in the carbs.

Thanks

 

[Sportster-2001-951C-Stock]

PTO carb internal filter always catches more fuel system trash thus often is the first to become plugged.

If you have a cylinder that is not firing this will damage the cylinder. A quick way to find which one isn't firing is by touching the spark plug shell or cylinder head near plug and feeling for heat. The cold one is the dead cylinder.

Those carbs need to some off for a thorough cleaning IMO but while playing around with it remember a little oil will help avoid damage and a carb that isn't fueling premix also isn't providing lubrication.

 

[Austrian Rotax]

ok but the engine always felt like it ran on both cylinders, it runs very smooth and no major vibrations when warm. also ive been reading that you should always replace carb base gaskets those are the ones that go from the carb to the RV cover I think, has anyone taken off carbs and re-used those gaskets without a problem as long as they look okay?

I hope to get the carbs off the engine but id like to know that first, I should have asked earlier.

Thanks

 

[spx787]

If they look OK, you can try to reuse them, however it's usually a good idea to replace them.

You can go and get gasket material (available at any auto store) and cut some out yourself using the old ones as a template. That's what I did and it has been working fine.

 

[Sportster-2001-951C-Stock]

If the gasket are in good condition usually they can be reused without any problems but the correct way is to replace them. I'm guilty of reusing them most of the time but I consider this a shortcut.

I've seen a lot of those gasket not installed correctly and in that case air leaks occur. Air leaks cause a lean cylinder which leads to damage.

Also, if your engine loses RPM while it's at WOT RPM's tend to drop off this is often caused by a lean condition meaning there is not enough fuel to keep the piston from overheating and perhaps expanding too much under the conditions (like approaching a partial lean seize).

 

[LouDoo]

You may want to put just a dab of marine or heavy duty grease on the carb. base gaskets, just enough to hold the gaskets in place while you install the carbs.

Lou

 

[Sportster-2001-951C-Stock]

You may want to put just a dab of marine or heavy duty grease on the carb. base gaskets, just enough to hold the gaskets in place while you install the carbs.

Lou

I'm glad you mentioned that, b/c it's a great idea in so many instances.

 

[Austrian Rotax]

ok thanks very much I intended to get working on it but on my local kijiji for Ontario I saw a mint looking 1995 sea doo xp 717 with a blown top end, he was only an hour away from me so I negotiated very hard and he eventualy agreed and I got the ski and trailer for $150, he also had ownership papers and trailer papers! I coudnt resist and picked it up, Im sure there is going to be quite a few things wrong with it mechanically, I didnt even bother looking under the seat when I bought it, it was so cheap I just didnt care lol. So the carb job I was supposed to do I hope I will get the time today and tommorrow. After im done with my 96 xp carb job Ill have a look at my 95 xp, one project at a time.

 

[LouDoo]

The 95XP is a great ski, almost the same top end as you 96 it just takes a little longer to get there. It's the most trouble free ski I ever owned.

Lou

 

[Sportster-2001-951C-Stock]

What a deal, I love those skis man!

 

[Austrian Rotax]

hi guys, sry late on an update I couldnt help but get distracted with my 95 xp, well I got both carbs apart from my 96 xp and the PTO carb filter is I would say 3/4 way plugged up only about a quarter of the filter I can see daylight out of, that explains a little lower compression on the PTO side. I sprayed carb cleaner all over the carb after I had removed all rubber gaskets and diaphrams, Mainly spraying throught the high speed and pilot jet. Also I didnt want to touch the needle and seat so I didnt take the needle out, I trust its okay as I never had any low speed bogging problems. Unfortunately the carb to RV base gaskets are junk, the carb mounting bolts were extremely way over-torqued and I think I was on the edge of stripping the head off the bolt using a bit over 1 foot of leverage and pulling as hard as a could, the gaskets were paper thin as well as cracked.

So for cleaning th carb filters I know carb clener is no good for that, my manuel says compressed air but I lent out my compresser, is there another way recommended?

Also with decently dirty carbs, should I take out the fuel baffle thing out of the tank to inspect? My fuel gauge doesnt work but I really dont care for my fuel light much. I did drian the old gas out of the tank when I got the ski.

Thanks everyone

 

[IDoSeaDoo]

The fuel gauge needs a new style plastic float. The old ones soaked up the ethanol in the modern fuel and sunk to the bottom. They are junk. A new style plastic one can be had for $20 from various sources. I wouldn't worry about the fuel baffle, but I would pull apart and make sure your fuel selector is clean and that you have no grey fuel lines remaining. Also, I heard that the three tiny transition ports can get plugged up (the ones directly under the low speed jet). Make sure those are flowing freely.

 

[Austrian Rotax]

Just late update, Im waiting for my local dealer to get the Carb base gaskets at the moment and is there something wrong with my local dealer? they are charging $25.00 a piece for one internal carb filter lol, seems a bit much for a tiny filter. And $10.00 each for a gasket, which is a reasonable price I think. So I read around and to clean the filter just spray carb cleaner in it but immediately wash it off Ill try that first but if anyone has a better way please let me know

Thanks everyone.

 

[96spxpos]

yea that's nuts... the entire carb rebuild kit, which INCLUDES the filter is like $34...maybe that's a fair price for just the filter, but I wouldn't pay for it..
Also, I think you're talking a Canadian $10. I think that's more than our $10?
anyway, I think I paid like $2.00 a piece for my carb base gaskets from SBT.
I think you can get decent shipping prices to Canada.. its worth a shot. it you visit shopsbt.com, you'll at least get a shipping price RIGHT AWAY just to check it out