problem with carbs/floats/spark

Ok first off--

This is my first post, thanks in advance for all the help I've gotten so far from reading all the threads-- They have been super helpful.

I have an 85 xj700 with 10,500 miles on it. It had been sitting Since 07 before I bought it back in November, so I took it to a shop and had the carbs cleaned and rebuilt. I DID NOT replace the floats, and I believe that is the problem.

It started flooding from between the two right carbs out of that little spout, so I took off the carbs and drained out all the gas and opened up the fuel bowls. I made sure the floats were not catching on anything and free-moving, put them back together and put the carbs back on. I let the PRI go till the gas came out and switched it to ON and fired up the bike. It ran fine, idled fine, no gas flowing from between the right carbs, so I took it for a spin. It ran good for about 5 mins then it started to feel like it was missing on the hiway, bogging and opening up with the throttle in the in a fixed position.. It would go 65mph but it felt like it was struggling and it sure did eat up the gas!! I got back home and checked the spark plugs and #3 was wet, shiny and black. I switched it out and it ran fine til I got to the gas station. The bike felt doggy again after I left, and then revved up to about 4500k rpm at a stop light. I stopped and turned the idle knob down until it was back to about 1200 rpm and drove back home.. It ran like shit on the way back and wanted to die at intersections if I didn't rev the engine, and I sure could smell the gas!! When I got home it died before I came to a complete stop.. I started up again and had to roll on the throttle to get it fired up, and gas was coming out of the spout between the two right carbs again.

It should be mentioned that I also installed a new Yamaha Petcock from partzilla, and that the spark plugs are not what the manual calls for..

Any help would be greatly appreciated!!

 

The problem is that you took it to a shop.
You have a flooding condition and the floats are not to blame (they are solid floats).
This tells me that the shop did not provide the service that you paid for.

Step #1: remove the oil filler plug and have a sniff. You might have some gas in the oil, and that will need to be drained out, and new oil and a new oil filter installed. DO NOT start the bike again until the fuel has been removed from the crankcase, new oil put in, and the flooding problem has been solved.

Step #2: read In the Church of Clean

Step #3: read The Information Overload Hour

Step#4: order parts and get to work (member Chacal is a great parts source. His catalog is linked in the upper right hand corner of every page).

 

^^^ do dat^^^

Yep, your best course of action with these older XJ's is to do it yourself.
Don't fret, there is nothing the people here can't talk/ walk you through.

 

I have the same bike (bought with 10,500 miles on it and had been sitting up for about a year.) and went through many of the same problems with the carbs. More than likely either your float needles are leaking (most likely) or the floats were set too high. When you remove the carbs for a proper cleaning float the floats in some gas and you'll see immediately if one or more is not floating. If you are going to try and keep the bike I suggest you get some tools, a service manual, and tackle the carbs yourself. (I had a shop clean my carbs right after I got the bike.) If you have any mechanical experience you can clean the carbs if you follow the instructions in the "Church of Clean" on this site. (Someone will post it for you.) No short cuts, no assumptions, no hurry. Trust me, I tried it all before I finally went step by step. My bike was running very rich, fouling plugs, and getting about 30 mpg when I got it, and didn't improve much after the shop cleaning. After going through the process myself, the bike starts easily, runs great, the plugs are perfect, and I get 41-42 mpg with reg gas. No shop is going to be as careful in getting it right as you will be

 

K-Moe,

I had to drain the oil already due to a malfunctioning petcock, hence the new one. The new problem occured after putting the new petcock on and the oil level was fine before I put the new petcock on-- but I will check and change again as I suspect there may be some gas in the case now.

I talked to the guy from the shop over the phone (I moved out of state recently) and he said he would go over it again for me if I sent it to him.. It will cost me $60 plus shipping and parts.. He insists it's the floats, saying something about the foam soaking up gas over the years and not being as buoyant as they used to be. I guess I could try the float in some gas before I ship them off.

I started to read the church of clean and it seems a bit discouraging if I have to separate each carb to properly clean them all, as well as re-synching them after.. Here are before and after pics the mechanic sent when he cleaned the carbs, I'm assuming he didn't take them apart either..

 

The first image is the before pic, second pic is the after..

 

He's wrong. Yamaha used impermeable floats.
Any re-work should be on his dime.
Would you trust someone to re-do a job that wasn't done right, and who also wants to charge you to re-do it?
His statement about the floats not being as bouyant as they were when new tells me that he never bothered to check the fuel levels in the float bowls (a job that takes 5 minutes to do and requires no parts). If he had checked the fuel levels he would have seen them go to high and should have corrected that before returning the bike to you.

Breaking the rack is not a daunting as it seems, and each step is straightforward; it just tkes careful organization. You may not need to do any of that though. I suspect that all you need to do is tend to the fuel levels, and make sure that the float needles are sealing and that the float needle seats gaskets are not leaking either. You reported that the bike was running well before it began flooding, so it's not likely that any other work would need to be done on the carbs at this time.

 

Unfortunately,those pictures don't really tell you anything.its all the little tiny holes and passages you can't see that will give you fits and make you think something else is wrong.take a breath slow down, those carbs didn't get dirty in ten minutes so they don't get clean in ten minutes either. Now why is everyone telling you it's the carbs? Except for someone pouring gas into the oil fill.Thats the only way gas can get to the crankcase.go to the something new something naked link.There is a cut apart carburetor so you can see what your working with....there is nothing wrong with not wanting to to clean em but to get that bike running Right. You're gonna need to clean em. Get stuck?ask some body!! The people here know these machines inside and out.and they don't even make fun of people who ask dumb questions.. Well maybe a little.. So in closing go clean your carburetors and as Kmoe said float level circuits
might be as far as you need to go but if it was me and I had them off I'd clean em.

 

K-Moe,

Is there a step-by-step on how to check/correct the fuel levels in the float bowls? I suspect it's the #3 carb because of the spark plug fouling out and the flooding coming from that side of the carbs..

When I first got it back from the shop it started just fine and rode down the street for about 5 minutes until it died in the middle of a busy street 5 blocks away from his shop!! I called him down and he came and got it started. He had to hit the throttle wide open to get it started, and I rode it home from there.. I took it on one 30 mile ride after that and drove it around town, but the faulty petcock began to leak and it never really ran at 100%. When he rebuilt the carbs he was telling me to buy new floats because he thought the old ones were no good, but I asked that he try and clean the ones I already had.. He said they cleaned up pretty good, but he said I will have to replace the floats eventually.. Every time I called him back about the bike running like shit, he attributed it to the worn out floats..

Again, please let me know if there is a step-by-step on how to check/adjust fuel levels in the float bowls.. Thank you everyone for the responses, it feels like I'm not alone after all!!

 

http://www.xj4ever.com/setting fuel levels.pdf

 

Just to be sure the gas tank was flushed and filled with new fuel and also inspected for internal rust. It doesn't sound like the mechanic that did the carbs was all that knowledgeable given his latest diagnosis, but even a good rebuild of the carbs can go wrong if the tank is contaminated. Most of the members here suggest adding an in line sintered bronze fuel filter to reduce the risk of contaminating the carbs once they have been thoroughly cleaned.

Even if the mechanic replaced the float needle valves I would still question them, as some of the aftermarket parts are just cheap and do not work. As K-moe suggested, if you decide you need parts Chacal at info@xj4ever.com will be your most reliable source of quality parts.

 

As I said earlier, I had a similar problem with the same bike. I did not have to break the rack, but did thoroughly clean the carbs, do a bench sync, wet set the floats, reinstall the carbs and set the pilot screws and do a running sync. Personally, I would not break the rack unless you have good reason to suspect a problem with the seals. Follow the instructions that you have been given and you'll be fine. As I said, I have the exact bike and exact carbs so if you want to give me a call just let me know.

 

Thanks for the responses!!

XJRider, thanks for the pdf file!! I will have to buy the carb adjustment tools--

Rooster53, I painted the bike while I was waiting for the petcock to come in the mail, and the tank had quite a bit of rust flakes in it.. I shook the vast majority of the crap out of there but there was still a very small amount in the tank when I put it back together. I think my next move while I'm messing with the carbs will be to try and coat the inside of the tank.. Any suggestions on what product to use will be greatly appreciated..

Tabaka45, thank you so much for offering to walk me through the process-- I May have to take you up on your offer.. I will have to buy some more tools in order to tackle this project, I was looking for some on eBay today.. If anyone here has some tools they want to sell please let me know asap, I am a college student and I want to get this done as cheap/fast/correctly as possible..

Thanks again guys!!

 

http://www.caswellplating.com/epoxy...ler-motorcycle-tanks-up-to-10-gal-1-pint.html

One of the atvantages to the Caswell system is that the tank should have some surface rust for the epoxy to bond fully.

 

I would not line the tank unless absolutely necessary. Someone on here will post a link on how to remove rust using electrolysis.

 

Sorry started to reply to the electric tank clean and got distracted. I have seen the process and basically you make a wooden plug to fit in the cap bung,drill a hole in the wood slide a piece of steel in make sure it doesn't bottom out.. it can't touch anything else.
fill with water. take your battery charger hook the ground cable to the piece of steel. hook the positive to the tank. turn on the charger the piece of steel draws rust to it. He stopped every hour or so and cleaned the steel piece dumped out the water and refilled the water.never done it myself but I was impressed with the results.there is alot of video"s of this on u tube.if I didn't explain this right

 

There is an electrolysis thread here somewhere. It's an easy and inexpensive process, but the tank still needs to be treated to prevent further rust. My usual followup after electrolysis is a phosphoic acid wash to pickle the bare steel.
I do agree that the tank might not need to be lined, but following rust removal it's not uncommon to find pinholes, and the liner is the easiest fix for that problem.

 

And one other thing always run an inline filter it's cheap insurance.even if you have a clean tank,there is dirty gas everywhere.

 

Ok everyone, Update!!!

I took off the carbs today and removed to fuel bowls to see what I could see.. It seemed that one of the floats (#3) was hanging a bit lower than the rest, so I decided to take it in to North Coast Cycle (Eureka CA) and let them have a look.. The mechanic looked it over for 5 minutes and found a small grain of sand preventing the #3 carb needle valve from closing all the way.. He got it out, took an air hose to my carbs and blasted air through some spots to clean it up.. I just now got it all put back together and the tumbler in the ignition won't turn when I put the keys in, spare or main... I want to see if it worked, but now the bike won't start... What can I do now?!?!?

 

Did you take your bike into the mechanic or just your carbs?
Did the mechanic have your keys?

Try spraying some penetrating spray into your tumbler (AeroKroil, PB Blaster) see if it frees up.

 

I just took the carbs in, the mechanic didn't touch the keys.. I thought about spraying some pb blaster in there, I just wasn't sure if that would hurt it or not.. I'll give It a shot and see what happens..

 

Ok!!

I tried the PB blaster trick and it came un-stuck in 2 minutes!!

So,

I took the bike for a spin around the block and it seems to be back to normal.... Lots of power, idles at the stop signs, and sounds waaaaayyy better!! I would have taken It further but it just rained here so I'll have to wait and see if dries up enough for a longer cruise..

 

Now, while you're enjoying your motorcycle, take the time to learn how to unstick grains of sand (and a host of other things) yourself. Also get an inline fuel filter, because that sand was most-likely rust from inside of your fuel tank, and you don't want to let any more get to the carbs.

 

I got an inline filter from Napa and put it on before I started it up.. I just need more tools, and a bit more confidence but I'm getting there. I am also having problems with my ignition switch now, I have another thread about it as well...