96 gti not running good unless i choke it halfway. found exhaust leak

[motoring]

I changed all fuell lines bypassed selector blocked off one supply port . left the vent as factory contions I check the check valves etc I used after market filters I put two in line before carbs
this is a twin carb 717 motor .
motor only runs good with the choke plate half closed and it has to block the center of carb (the center being the about 3/4 inch round don't know the proper name if that part of carb)
the guy before me said he had a bog problem. so I rebuilt carbs with after market kits I used original spring inside carb for needle valves.
did find that the exhaust is leaking under the purple pipe and above the white manifold but that's only at high rpm. the bogging down is happening at mid throttle it wont rev up unless I close the choke halfway.
maybe I have two problems ?
I did do any adjustments to carbs like the needle valve arm is the only major adjustment I can think of
I will fix the exhaust leak first if possible.
I ran it yesterday and it runs with the coke half closed nice but I don't know the speed it seems slow but I'm used to my hydrostream venom that did 110 mph . it felt like 40 mph though
could the exhaust pipe be bad or just the gasket the guy before tried to fix it I believe . but he wasn't very handy and did lie to sell a lot lol

 

[motoring]

there are two vents I left them like factory .

 

[mikidymac]

Nope, your issue is lack of fuel and running lean if you keep running it you will seize the engine.
1. Your first problem is the aftermarket carb kits. As we keep preaching they are junk and will cause exactly what you are experiencing.
2. Get rid of the 2 aftermarket inline filters, they are probably causing a restriction too.
3. Don't bend the carb arm. Now that it is bent you need to replace it and check pop off.
4. Fix the exhaust leak.

 

[motoring]

I didn't bend the arms .I left them.
the guy before me had this problem and sold it. he said his mechanic rebuilt carbs but they didn't look like it to me they were dirty dirty . the diaphrams that were inside hade a red dot that hits the arm were they original? because the cheap ones I got are not.
I didn't know the carb kits are no good ! any parts to cheap kits in particular. yes I agree lean . guess ill be changing them again lol
the check valve I noticed are thicker I didn't like that. the little piece of plastic
I wonder if carbs came from a different ski,do you know the factory jet sizes . mine is the twin carb 717
definitely fixing water leak .
I bought the ski because it was fresh water and the compression is 150 . I figure I can fix why he was selling it he told bogging down( so I didn't create the problem I bought someone elses lol , $700 for very clean ski and trailer no rust on motor . but it don't run right lol so paint don't matter much yet .) . but the carbs not sure ? and I don't know what the last few owners did to it. so I cant trust what was done to it. , I use to only work merc outboards v6 race motors this is a different animal and I ll learn but now I know I need the advise thanks this is my first one

 

[motoring]

yes I know running a two stroke will seize if lean. !!!!!!!!!
I used to run pyrometers on my race motors 10k rpm high hp
not fool proof but it tell you right away if the motors lean and at that point shut it down and get towed it it saved my motor at least two times. once do to a clogged fuel filter.

 

[mikidymac]

Ok, I would suggest getting the 2 carb basic rebuild kits with needle and seats from OSD seadoo, add the 80gm springs if yours are not black.. His prices are great, includes only what you need and are all genuine Mikuni parts. He even includes new base gaskets.

The carbs are pretty simple but one thing most people miss are the 3 small holes that feed from the pilot jet into the main carb throat. You need to see 3 clean strong streams when you blow carb cleaner through them. The other thing is to make sure you have the correct carb springs on the needle arms.
A 1996 GTI should have 130 Main jets, 67.5 Pilot jets. 80 gm (Black) springs, these do not come in the carb kits. 1.2 Needle and seats, Low speed screw 1-1/4 turns out, High Speed screw closed.

 

[motoring]

wow carbs way off okay high speed all the way in , clockwise ??
low all the way in clockwise them back them out 1.5 turns.
ill check the jet sizes
no the spring that came with ski are silver. so I need black
the arm do look bent bent I guess they should look straight so ill buy new ones.
the diaphrams that came with ski have a red dot that hits the arm are they factory or probably not. if probably not ill buy new ones.
ill double check the three holes
I have the fuel tank so clean now ill remove all filters just to see if they are bad . if same problem ill put the factory filter back
and down below I did leave the oil tank connected to the motor case to lube the shaft for the pump that I'm not using I also left the oil line going from tank to pump even thou the pump isn't spinning .
.
I notice when I removed the carbs that there were metal filings all over from the bottom of the choke plate to very bottom of carbs but I didn't fine the filings on the intake plate .(which I removed and took of the gear off the pump for oil injection. I always remove oil injection and I used the lines hooked up as if the oil injection was working to block the nipples from taking in air, dispite how many people believe in it . in this case I think a good idea the gear was cracked. and probably would have falled if not changed.)back to the filings under carb filings, which leads me to believ the carbs came from a blown ski motor I run it yesterday for a bit and need to do a very close inspection to see if theres metal filings if so then the seller got me and the crank bearing probably shot. the compression and plugs read good but that don't tell me if the crank is bad. lol
again thank for help and any thing I did wrong please tell me I know I don't know about ski and trust that you do . I know the basics as far as its a two stroke and how they work . and I bought old because I know its simple . the new stuff I guess you need the computer from the dealer to trouble shoot . this ski is old school I believe anyway , thank again for help

 

[mikidymac]

I would just replace the diaphragms. The red part won't tell you anything.
Make sure you use the stock strainer. It is a filter and water separator. Make sure the oring on it is good.

 

[motoring]

another question. upon starting and running at times fuel was spitting up thru choke plate hole .and also inside the circle were the three holes are . and once I covered the hole inside the carb with choke plate from any direct air the fuel wasn't spitting around nearly as much. it seem mid range was the biggest problem seemed like to much fuel wasn't allowing the motor to rev past mid range rpm. but to get to high rpm the choke had to to half way closed and then no bogging and I know that's an indication of a lean mix. I have the ski on the trailer tied down in the water it was pushing my truck pretty good so I was hitting some power. is there anyway to much gas at mid or low rpm then to lean at top or the other way around . anyway I guess ill just get the carbs back to stock as possible .the jet could be way off also. and go from there.
It must be the arm and the spring !!!!! I think you nailed it there because the arm is bent on both and springs are wrong.!!!I'm used to working with a float carb not this system . the float is easy it just must be level basically . and this system is desigined in case the ski turns over. I never worked on this type carb . thanks have a good day

 

[benjilafouine]

I had a very similar issue two years ago on my GTI. The guy who rebuilt my carb used the wrong parts (arm and spring I believe as you mentioned). He used the parts that came from a jobber kit.

My ski would start OK but it would not go into high speed easily. It would kind of get stuck on the low jet. When I pulled the choke a bit or if I go full throttle, it would jump from 20 mph to 35 mpg and would not go faster than that (supposed to go at 42 with my weight on it).

Since the season was coming to an end soon, I purchased a new carb and the issue was fixed right away. I still have my old carb in a box with... a bad arm and spring...

Benji.

 

[motoring]

yea that must be the problem someone bent the arm and put the wrong pressure spring . I hope the previous owner didn't ruin the crankshaft by running it lean I guess it wasn't his fault unless he did all the top notch mechanic work lol.

I wish every two stroke engine came with a pyrometer and everyone would know their going to have a failure due to a lean mixure. if they knew that they would save a lot on fuel if the mixture is too rich then every two stroke would have a pyrometer mandatory factory installed lol . I guess now the o2 senser does the job it changes the fuel mixture on the four stoke engines .

 

[motoring]

you have the 717 motor single carb?

 

[benjilafouine]

I ran mine for 10 hours like that and actually, I am not sure if this was a too lean issue. With the wrong parts in it, your carb is supposed to hit the high jet at a certain regime, which it didn't because the parts were the wrong ones. Was it too lean? Don't know, not an expert but my engine has now 100 hours on it and it is still running just fine. Cross my fingers

Benji.

 

[wfo speedracer]

Those fake main diaphragms suck, as has been said you can no longer go by the red tips, yeah they copied that too, you have to look really closely at the diaphragms themselves, the curvature is all wrong and they will hold the needle and seat open and make the carb run like sh!t, the needle arms are made wrong also.

 

[mikidymac]

I can't believe companies keep selling this crap. You would think at some point the word would get out enough and people would stop buying it but I guess not.
These cheap products flooding the market are killing me. I recently bought a solvent brush at ORiley to clean some cases and the minute it hit the solvent all the bristles fell out. Yup, Made in China.

 

[motoring]

I can't believe companies keep selling this crap. You would think at some point the word would get out enough and people would stop buying it but I guess not.
These cheap products flooding the market are killing me. I recently bought a solvent brush at ORiley to clean some cases and the minute it hit the solvent all the bristles fell out. Yup, Made in China.

thank god for good furums as this one otherwise we would be 100 percent screwed having to bring everything to the dealers we would be broke and who says the kid working at the dealer knows what hes doing !!
I have another good one I had my roof of my truck painted and the front bumper cover now I have a water leak coming from the front window go figure sometimes I give up and say why bother . but these furums are the only hope.
thanks for the help !!!!

 

[motoring]

I ran mine for 10 hours like that and actually, I am not sure if this was a too lean issue. With the wrong parts in it, your carb is supposed to hit the high jet at a certain regime, which it didn't because the parts were the wrong ones. Was it too lean? Don't know, not an expert but my engine has now 100 hours on it and it is still running just fine. Cross my fingers

Benji.

my plugs are reading rich they are black and had looked wet . but one thing for sure the carbs are not right . I should have tried when I went for a short ride , to open the choke up to see if once past the mid range if the motor would give more power but two strokes are so unforgiving if they run lean so I didn't do it .I ran it with the choke half open or closed depending how you look at it lol and it ran fine but it didn't feel fast enough .(I also need to get my phone to do a gps app to see how fast I'm running I heard my ski should almost hit 50 I weight 170. I know with the choke half closed it has to reduce the air and reduce the chance of running lean. maybe ill try it once and shut down right away and read the plugs.

 

[benjilafouine]

I also have the 717 and my weight is about 220 pounds and I get 42-43 mph max. Maybe I should lose a bit of weight...

Benji.

 

[mikidymac]

my plugs are reading rich they are black and had looked wet . but one thing for sure the carbs are not right . I should have tried when I went for a short ride , to open the choke up to see if once past the mid range if the motor would give more power but two strokes are so unforgiving if they run lean so I didn't do it .I ran it with the choke half open or closed depending how you look at it lol and it ran fine but it didn't feel fast enough .(I also need to get my phone to do a gps app to see how fast I'm running I heard my ski should almost hit 50 I weight 170. I know with the choke half closed it has to reduce the air and reduce the chance of running lean. maybe ill try it once and shut down right away and read the plugs.

Do not keep running it if you are experiencing carb issues. Pull the carbs and service them correctly.

 

[motoring]

I also have the 717 and my weight is about 220 pounds and I get 42

does that speed put a smile on your face ?
whatever speed I was doing I wasn't smiling much but I guess I was doing 35 40 so I guess it wont go much faster. does the front of your ski lift out the water and the ski rides on the back plate? mine didn't lift the front !

 

[mikidymac]

At top speed all the skis should be up and out of the water. IF you are just plowing through you have a problem. Standard top speed on a GTI is about 45 mph.

 

[motoring]

Do not keep running it if you are experiencing carb issues. Pull the carbs and service them correctly.

yes I agree . it only takes seconds to destroy a two stroke motor

 

[motoring]

At top speed all the skis should be up and out of the water. IF you are just plowing through you have a problem. Standard top speed on a GTI is about 45 mph.[/QUO

okay maybe there was a shim to angle the pump a little to lift the nose, or back to the carbs and lack of power . I have to find all the problems that past owners fixed up lol and refix them.
I did another thing I'm sure is bad I bought one of the after market nose cones for the pump with the anti rattle it has the spring in there I'm sure you know what it is , and being new to this its all a learning curve but I wont even touch anything until I check this forum . I'm sure your going to tell me to get rid of it ??by the way it still rattles but not as much. which tell me its garbage at least it was only like 15 bucks .

 

[mikidymac]

The anti-rattle cones are fine. But in all honesty the seadoo pumps will still rattle. It doesn't hurt anything it is just part of their design.

 

[motoring]

I checked engine theres some metal filings inside carbs again which tell me the exhaust water leak is getting into crankshaft area. the previous owner didn't see it because it can only be seen when ski in water tied town to trailer and hitting full power. then it shows . the cylinders compression are still good . all I can do is sand down mating surfaces install new gasket and hope to get some time out of the motor. fix carbs also before running .
if still no good at that time then well not sure yet.