"Smoking like a JET"

:cry: The guy at the shop finally got my bike running, he tuned the carbs, it leaked gas :cry: he changed all the gaskets, etc and it worked :wink: as they was test driving it, it started to smoke :? and smoke, and smoke :cry:
He said it sounded good when he started it. That makes me think that it was just moisture in the system (from being outside forever) and NOT a cracked head or something (right :?: ) I am sorry I do not any more information just yet, the last I spoke to him, the plan of action was to "let it run for the rest of the day and see if it will stop smoking, because to redo the heads and pistons, etc would cost more than the bike is worth"
ANY suggestions that I can give him would be GREATLY appreciated.

 

Did he drain the crankcase and refill with new oil, and put on a new filter? If not, you're probably running with a crankcase full of gas due to the leaking carbs....the fuel would drain down into the cylinders then trickle down into the case. What can happen is that the case fills up with gas, a lot of the oil with float until it gets to the intake ports, flow back through the carbs and fill up the airbox. So, did he check the airbox and filter? Is the filter clean or soaked up with oil and a good amount of oil in the bottom of the box? What can also happen is that the case fills up, the oil pushes up through the crankcase vent tube that goes to the airbox. Either way, you end up with a whole lot of oil swamping the airbox. Get it running, and you have a crankcase full of gas, an airbox full of oil, the carbs suck oil in, the crankcase tries to run with gas as a lubricant. etccc........that could cause a whole lotta smoke!!!!!!!

I don't think you have to worry about head and pistons based on what you have said.

Let us know how things go.........

Dave

 

I like how your name is KRAYZEE Smoke. haha.

Anyway, was it BLUE smoke, or BLACK smoke?

And if you learn to do the work yourself, head removal and doing pistons etc... not a LOTTT of money, depending on where you get your parts, it's more time than anything. So LABOR = $$$. So learn to work on your bike yourself, however long it takes, and you can save loads of $$$ and be satisfied it was done right - most shops suck

Remember - the bike is 27 years old. If you can't fix it now - hold on to it till you can.

 

when i was new in biking, i had a shop that was spot on. that and the guys i rode with were spot on...

me, im not so satisfied the job i do is right. i NEED a shop. i use Carl hes a straight up guy. unfortunately hes 86 miles away...

i WISH i had more mechanical skill....

 

You're never too old to learn...

 

+1 on checking the oil. i have had the same smoking problem happen on a seca II i had in the past. now, mine was not due to fuel, it was due to my stupid ass putting too much oil in the crankcase because i couldnt tell if there was any in the sight glass or not, but regardless, the same principle applies. when the crankcase is overfilled, its common to see oil get pushed out through the breather tube into the airbox, and it will smoke like a sumbitch till it burns off enough to stop sucking oil. I would suggest an oil change, making sure of course that its full to the proper level.

 

Ok, I have talked to the mechanic he said "it is low on compression and the oil is at spec, the cylinder wall is washed out, the cross hatching is gone, it is not oil blow by (whatever that means) it is blue smoke, burning oil smell" "it is smoking so bad that oil is dripping from exhaust"
OUCH

 

Krayzeesmoke it almost sounds like your having the same problem i am. My bike is pushing out some gray smoke badly at times and the smoke even smells like oil. It just isn't pushing oil out of the exhaust. Did the mech do a compression test on the bike to see if it could be a piston ring? I did one on mine yesterday and the numbers where good. Which just raises more questions. I'm starting to think that my vavle oil seal is bad,

 

question to everybody - the mechanic is saying that he will do whatever I need him to do, other bikers at work are telling me to sell it and put the money I would use to fix it towards another bike.
so, how much work is it to fix ring/valve job? what should I cost? at worst, what other engines fit the 1982 xj750r Seca frame?
thanks in advance

 

The 750 Maxim puts the shifter in the wrong spot, if you put on a straight shifter, you end up with an upsidown shift pattern. And 8% taller gearing !!

650's drop in, but you need the 650's carbs too, or swap 16 jets into your carbs. 8 of those are not available.(?)

Any odd chance that your motor is fine and your exhaust is loaded with oil?
What were those compression numbers??
What exactly do your plugs look like??
This guy could be messin' wit ya !!

 

i am not sure of the #'s but will try to find out,
he did say that they didn't change the oil, they topped it off, so I am going to get it back and change it myself (save about $40) and pray it is all it needed.

 

In my opinion, if it smokes and passes oil that badly, its too late for an oil change. the firts post said it leaked gas and then he test drove. did it leak a bunch of gas into the crankcase and dilute the oil causing the piston rings to burn up? I know he says the level was good but how trustworthy is this mechanic? just thinking out loud-something sounds fishy.

 

If they let it sit and run all day at high idle WITHOUT a box fan on it, they coulda toasted the rings themselves !!

I had 100 PSI in a CYL of my 750 Seca, and put in the correct shim, got 147, what are your valve clearances?

( hint- - the better XJ gurus hold their advise until you post-up the facts )

You could pull the exhaust off and run it, see if it smokes.
If it doesn't, you needed the exhaust off to somehow rinse it,
If it does, you needed the exhaust off to remove the engine.

It's easier to buy a $200 engine than buy rings, gaskets, valve work, ETC.

 

Where do I find a $200 engine?
I am getting it back from the shop next week. I will do oil change myself and be able to report exact details.

 

Another thought, if the shop charged for a running sync and tune, but they didn't check or adjust your valves, they wasted that part of your money.

I bought a somewhat complete parts bike from a junkyard for $200, with engine.
I bought a mostly complete 650 turbo for less, it ran.
and, I bought a stripped 650 maxim with motor for $ 9.99 off "the bay".
The deals are out there.

 

Dude this shop is totally clueless about your bike. Not a clue man.... This site is waaay more full of info than that guy will ever have. He's got no idea what he's doing and will happily charge you to play with your bike.
If he did run it all night without a fan, your rings are def toast. And +1 on snaykes comment. If gas got in your crankcase that'll mess a buncha stuff up.
Oiy.. Kraz, just read up here, do your own tests, and just do it yourself and save a crapton of money. Only if you reeeaaaally want this bike to work though. If you just wanna give up and sell the bike, I'm sure there are people here that'll get her back on the road, or use her for parts. Up to you man.
My 700 had a slew of probs that I myself fixed with the help of this site and no mechanical knowledge at all. You can do it if you're determined.
But in order to help you, we need facts, and pics, and detailed info. Good luck soldier
-StreetLegalKid

 

I still think you should drain the oil, change the filter, and refill with new fresh clean oil. If all he did was top it off, you could now have topped-off gas-contaminated oil. CHANGE it. There will probably be a few minutes of smoke as oil dribbles burn off the bottom of the engine, but see what happens from there. While the oil is draining, check the condition of the airbox to make sure that you don't havea layer of oil in there. I picked up one bike that had about 1/2 inch of oil in the box. It CAN happen.

Dave

 

Great news, I got my bike back and asked the guys to "just let me see her run" (I would try and do it but its my 1st bike and the front brakes are not connected, not the way I want to learn)
It didn't smoke, it ran for 5-6 minutes and nothing, they were dumbfounded, after they left, I put a box fan in front of it and ran it for another 10 minutes or so, and it barely started some black smoke.
I changed the oil yesterday and was running it for about 15-20 minutes, and still nothing! YES! Now my issue will be to reconnect the front brakes and such.
Thank you guys (and girls if any) for your support and encouragement, it is now NO LONGER SMOKING LIKE A JET

 

Good XJ, Good XJ, <he says while gently scratching it between the ears and under the chin>

See! We'll get you going!

Make sure that you have new fresh oil and oil filter in, and make sure you get the carbs cleaned.

I would recommend putting on a small fuel filter, too, while you're at it. It's just a precaution, in case some particle does happen to get through the screens on the tower. ( and it's not uncommon for the tower to just fall off inside the tank) the last three bikes I brought in had two of the towers off.

Now, get those brakes finished up so you can take it out for a spin! Once you ride it, you'll know you want to finish it up!

Congrats on the progress so far. If we had a complete gallery of before/after pics from everyone on this site, you'd be amazed at what some of these looked like. I'm sure that MANY were MUCH worse off than yours.

You're in good hands here. Keep us posted!


Dave

 

Crap crap crap crap
I rode the bike 3 times! It was GREAT!
Then, my dumba$$ gets curious "whats this little twisty thing on the handlebars" (dumb) I turned it , the engine raced, I turned it back and IT NEVER WENT BACK TO NORMAL (dumb)
I turned it off and now it sounds like the starter is out when I try to re-start it (dumb) and if/when it does start it races (3500 rpm)

 

what little twisty thing?


Dave

 

Are you talking about the choke?

There are not that many "twisting things" on the handlebar (throttle & choke), most of them are "clicking thing" :wink:

If it's the choke, maybe it's just a stuck cable. Try put some lube in it and see if it helps

 

I guess its the throttle cable, it is coming from the right-side controls down to the carbs :cry:

 

Well, if that's it can't you just replace/ re-lube it?

 

The engine was racing even when the cable was not pulling (all the little pin top things were down) I am afraid its something else, like stuck in the carbs, or timing belt or broken gears

 

First, you have to twist the twisty thing to be able to go anywhere anyway. So, did you twist the throttle while it was NOT running? Sounds like a sticky cable. Did you leave the choke on? That will make it idle high....the higher you set the choke, the higher the rpms will be.

If it's racing, it's not a problem with broken gears or a timing belt. If it were gears it wouldn't run, and it doesn't have timing belt.

all the little pin top things being down would indicate the choke is not on, so look at the other cable that goes down inbetween carb 2 and 3. Make sure that when you twist the throttle that it pulls all the way up, and when you let the throttle go, make sure that it pulls all the way back down AND THEN allows for a small amount of slack. If there's no slack the slides won't go all the way down, and the motor will race.

If it doesn't go all the way down, cable is sticky or somebody was messing with the cable hookups. Pull the tank and disconnect the cable from the clip. Now pull up and down on the carb lever. See if the carb slides bottom out again. Yes? sticky cable or cable setting needs to be taken care of. No? Well, now you have something stuck in a carb that is keeping the slides from bottoming. If it doesn't go UP when you turn the throttle, the cable separated from the control in the grip.

Curious, have you opened the airbox? If so, I'm sure you made sure there's no obstructions to airflow. If not, open it and doublecheck that there's not a mouse nest or something in there. Been there, done that, cleaned that, smelled better in there later, too.

Don't get discouraged, we'll help you get it straight. Many of us have been in deeper than this.

 

I was saying broken gears, starter or timing belt because it acts like it doesn't want to start (grinding)now and when it does it goes directly to 3000+ rpm
I need to figure out how to post pictures and video and this would be easier I am sure
I have cleaned the airbox out, no nest (great) and I blew the filter out with air compressor (the bottom was saturated with gasey oil mixture) until I score another

 

grinding sound - as in strong battery and a bad starter? or Weak battery that's not got enough juice to keep the starter engaged so it chatters?

goes right to 3000 rpm - does it sound like it's running smoothly at that speed? Does it do that consistently even when cold? Mine starts up, goes right to 2000rpm and climbs right to 3000 in a few seconds as she warms up. Once she hits 3, I bring the choke open until she drops to about 18. Then I take off riding. After a minute or so, I through the choke off the rest of the way unless it's really chilly in the morning. Then I may leave the choke on about 5-8 miles. Once she holds that idle well, and want's to climb a bit, I throw it off the rest of the way.

All that to say.....3000 isn't bad when just starting up. If it won't come down When you release the choke, then that would seem to point to either a sticky choke cable (watch underneath the tank to see if cable is releasing all the way and allows for a slight bit of slack at wide open choke. Otherwise, maybe time to go back into the carbs.

dave

 

If I take the carbs off, will that mean I will have to pay the shop to re-sync them again, or should they stay pretty good as long as I am careful

 

UPDATE - the high rpm's are the choke cable rattling and sticking, I will deal with that later.
But when I put it in gear it dies, everytime... any suggestions, it will idle forever, but as soon as it goes to gear, it turns off.
Sorry for being such a drain on everyones knowledge

 

I assume you mean putting it into gear from neutral.

I also assume you don't have the kickstand down. if you do, it is supposed to shut off as a safety feature. Either brace your legs and have the kickstand up before putting it in gear, or if you're trying to diagnose things, put the bike on the center stand before starting.

Check to see if your kick stand switch is sticking. You can do a couple of things for that:

1. put the bike up on the center stand
leave the kickstand up, look at the plunger next to it and try to pull it out any farther. If it comes out a bit, there's your problem. If not, it still could be the problem.

2. Step 2- pull the seat off, trace the wires from the switch. Disconnect the switch and make a jumper cable to go between the terminals so you effectively bypass the switch. If that works, then you know the problem, and all you have to do is buy a new switch.

Keep us informed, we'll keep working on it. You're not being a drain...you're helping us to spread the wealth of knowledge!

dave

 

I will check that when I get home, I know that I was doing it with the kickstand down, but it seems that I also tried it up, but not for sure, but it makes since that I would have.
I also bought another bike on ebay, got it for $350, will be picking it up in a week or so, so be prepared for another million questions because it doesn't run, I will start another thread though so thanks in advance

 

Yep, keep in mind that you should be able to start the bike in neutral with the stand down, but in order for anything else, lift the stand before shifting out of neutral. Otherwise, it's supposed to immediately stall. that way you can't run anywhere with the stand down, catch a curve, flip over and kill yourself.... which HAS happened. There's been plenty of threads on that in the past.

Cool on picking up another! I only have two that don't run right now, and two more stuck engines on the floor.

Hey, fwiw, I just received my first bike Trophy today! I'm excited.

Dave

 

I just drove it, you are correct, I had the stand down (I am learning exactly how smart I am NOT) and I am starting to believe that the grinding is due to a weak battery, because it grinds and grinds then I hook up the jump box it starts

 

If the battery's weak and/or the oil's a bit thin, the starter clutch will slip off and make an awful grinding sound.

 

+1 to that. Get a new battery!

 

Yep, what he said........gotta have a good strong battery. Don't worry about "finding out how smart you're NOT". The ONLY way to learn something that you don't know is to ASK--which you are doing. I asked questions for 6 years before I felt that I knew enough about my bike to start answering questions. Heck, I'm working on my 3rd one for the road right now, received my first trophy just today, and have torn apart numerous xj and xv bikes. Replaced or r&red just about every part on my bike. That all being said, I just got done doing a carb rack for the first time. Put it back on the project bike just this afternoon and expect to get the DMV paperwork done tomorrow. The rims are getting the tires on on Tues, and am hoping to fire it up wed evening to ride to work on thurs.

Congrats on jumping in with both feet, asking questions, getting answers and learning how to do it as you go! Now, do an oil and filter change. Don't worry, we can walk you through that too.

dave

 

Congratulations on the trophy. What is the trophy for?