Vision totally broken after trying to repair the petcock

[b_racuda]

I did try to repair my petcock with a repair kit. At the same time I did try to remove the rust from the tank with Annitrol (mild fosfor acid). After these two repairs I was confidental that the bike will be even better. I did flush the acid away with water and after that put a little two stroke oil with first small amount of gasoline to protect the metal and gived a good shake. Then I did put my petcock back to bike.

Was very difficult to start and finally when started did run for a while, then white smoke from the exhaust and after that total stop. After that won't start again. Maybe something did go broken from the engine? Maybe gasoline find its way in the engine and now mixed with oil? Maybe gasoline was still having little acid and it broke something to its way to the engine. I don't know, I find it very frustrating and now ready to give up with the bike. Just on Friday I changed the brake fluids and the brakes were better after that.

Stupid me, before attempting to repair it was running really well. So if ain't broken don't fix it. Motivation now totally down, Vision goes to the garage and I try to gather motivation at the winter time, now I don't feel like taking everything apart again and finding where the problem is. I think it takes at least removing and changing the petcock, taking the carbs away and clean + check them, changing the oil + filter. Maybe I have to take whole engine and check at least the valves and valve gaskets.

[fret not]

WHITE SMOKE!   :o  First check the oil for any sign of moisture (water)  and also check the coolant for any signs of oil.  If these areas are clear then it may be the water in the tank getting to the carburetors.  You could drain the carbs and catch the fuel and any residue for inspection.  Should be ONLY fuel, no water, but if some water in the fuel that could cause some white smoke.  More likely water in the fuel would cause the motor to run very erratically and stop. 

I hope you have water in the fuel, much easier to fix.  Otherwise it might be leaking head gasket. (much more difficult and expensive to fix) :o

[b_racuda]

I think there is also something wrong with petcock. There was gasoline coming from the exhaust also and when taking hoses off the vacuum hose was full on gasoline also. Maybe I start by checking the oil and water first as you suggested. Then maybe buying a new petcock and emptying old gasoline and changing it also.

[Rikugun]

It may not be that the bike is "totally broken". Rather, maybe you didn't get all the water out of the tank. Drain the carbs and refill from a clean source i.e. test tank, temporary tank, "pony" tank, etc. Loosen the drain screws and let a bit of clean fuel flush through the bowls before starting the engine. Start the bike and see if the white smoke clears up after several minutes.

I'd also have to say based on your description the petcock rebuild was unsuccessful as well. Fuel is apparently getting past the vacuum switching diaphragm and drawn into the cylinders. Depending on the quantity it may have gotten past the rings and contaminated the engine oil. Change the oil and filter to be safe.

[Guerrero]

For me white smoke relates only for one thing-oil somehow got in to fuel.i know that from my lawn mower.when turned upside down for sec,then is really hard to start.and realy big clud of white smokes comming out for long time.but with throttle open for some few minuits it clears and runs fine.
But cant sugest,to run something serious as motorcycle like that

[b_racuda]

After sleeping overnight I have one thing in my mind, new petcock. Also noticed from older posts that there has been problems with petcocks and the petcock repair sets. I have to find new petcock from ebay. Is there any other model which petcock fits to Vision? Petcocks seems to be hard to find.

[fret not]

Fuel coming out of the exhaust system is possible indication of float in carburetor stuck in open position.  Possibly debris particles in float valve holding it open.  Since you had rust in the tank it is possible this is the "flooding" issue.

Fuel in vacuum line could be from a leak in the petcock diaphragm, and could also explain the fuel in the exhaust.

It is just a machine, so it is a matter of finding the problem(s) and sorting them out.  Your XZ is almost to the reliable state now, so stay with it until it is done. ;)

[b_racuda]

The carburetors are cleaned and Keyster components installed just 200km ago and fuel filter has been in place since. After trying to repair the fuel petcock the problems occurred so the petcock is the probable cause. I did take the petcock off three times after first installation and still it won't work.  So that money for the petcock repair set was wasted. After repairing my Vision for half of the driving season and then just few hundreds kilometres driving and then this incident, have to say it was very frustrative. I was going to tune my carbs tomorrow with dynamometer but have to cancel that.

On the bright side, maybe the engine is now cleaned from the inside with fuel, so some of the old skum is removed :)

[b_racuda]

Has anyone tried with simple manual petcock, so not vacuum operated? If I just put a plug to the vacuum line and find manual petcock. So there is one piece less to worry. Also the manual petcocks are much cheaper than vacuum operated.

[The Prophet of Doom]

My XZ400 came with a manual petcock.  What a nightmare - if left on it dribbled all over the floor, if left off the bike didn't go till the battery going completely flat reminded me I hadn't turned on the fuel.

Vacuum petcock rebuild kits aren't that pricey I think about $60 ea

[b_racuda]

I know the down size of the manual petcock but after trying to fix my vacuum operated petcock with rebuilt kit I have to get a new one. I don't think that I can fix my old petcock so I have to get a new one or fixed one. There seems to be one NOS petcock for Vision in sale on Ebay but it is still quite old even it hasn't been used, so the question is that are the inner parts O-rings and diaphragm hardened and will crack after short use?

Anyone know if the Suzuki Bandit 600 petcock fits to Vision http://www.ebay.com/itm/370745658789?item=370745658789&viewitem=&vxp=mtr ? I think that if the distance between fastening holes is the same and the upper tubes (inside the tank) are nearly the same I can give a try with it.

[Rikugun]

Anyone know if the Suzuki Bandit 600 petcock fits to Vision http://www.ebay.com/itm/370745658789?item=370745658789&viewitem=&vxp=mtr ? I think that if the distance between fastening holes is the same and the upper tubes (inside the tank) are nearly the same I can give a try with it.

Couldn't hurt to email the seller and ask for some measurements. I'm sure there are others that will fit from other Yamahas and other brands too. A manual petcock is a viable option but does have inherent drawbacks.

[cvincer]

I'm using a manual (no vacuum) petcock that I got on ebay for (I think $5) .... you just have to remember to switch it off at the end of the day.

Make sure the center to center  measurements of the securing bolts is correct.

(My vision petcock needed a new diaphragm, but a $9 part costs another $16 in postage to Australia)

[b_racuda]

I checked the measurements and i got 32mm from bolt center to center. According to seller the same distance is CBR petcock is 34mm. Well, my measurements was done in dark and may not be exact.

[cvincer]

I make it  34mm

[dpequip]

I would NOT use a Bandit petcock.  They have a reputation for failing on a regular basis and filling engines with gas. (Ask me how I know this) I have a Vision and Bandit.....The Vision still has its original petcock 30+ years and still works fine knock on wood.  The Bandit petcock failed after 8 years and 12K miles so I would not recommend the Bandit petcock.

[b_racuda]

Ok,  I have had Bandit once and had never problems with that. So now I ordered Vision NOS petcock from Ebay,  now waiting it to arrive to Finland.

[Guerrero]

As i wrote in my post.I ordered from,i guess,poland petcock rebuild kit for 16 usd.and it works great.Just dont know,for how long time =)
Or the damage of your petcock is more major?

[b_racuda]

First I did order the repair kit which was made in Japan. But it didn't work, I don't know why. Maybe my petcock was too corroded or something like that. After several reassemblies I was tired to do that again and just leaved it. After one night sleep I decided to try with new one, hopefully I don't have to touch it never again considering that the old one lasted 30 years. Today the new petcock arrived, have to try with that (11H-24500-00).

Anyone know if it is possible to see from the original package which is the year of manufacturing? There is two number series 31-9821-0 and F850129A.

[b_racuda]

At the moment oil and filter changed (fourth time this summer with under 500km riding), petcock changed and put new fuel to the tank. The old oil smelled a lot to fuel so there was fuel inside the engine. Started and it's alive! Seems to work ok with new petcock, even idle is back. Now have to recharge the battery, it had just enough power to get Vision running.

We have scheduled a long trip with motorcycles next weeks friday. I hope my Vision will work the whole trip ;)