Oh ohh.... Combustion chamber fishing?????

So I get to the second to last shim for my valve adjustment, and the cheapo wire tie, tie wrap, zip tie thingy I was using broke off the tip (about 3/8") in the spark plug hole. Can anybody tell me whats the best way to get it out or if I even need to. I'm gonna wait for you guys before I even look at the bike again. Thanks.

 

Use a small tipped vacuum. Is the tip in the chamber or in the intake/exhaust of the valve you are working on?

 

I cant see it but as you know that's a small hole to look through. But I rotated the cams several times before I realized it was missing. So I don't know if its still there or worked itself somewhere else. Im not very knowledgeable about the inner workings. I try and rig something with my mini shop vac. Which is worse out of curiosity, valve or chamber?

 

I doubt it "worked itself" anywhere else. Most probably just bouncing around on top of the piston.

 

If it's the PLASTIC tip, I wouldn't worry about it too much...it'll burn up real quick.

 

Unless it gets caught under a valve head when the piston is on its way up...

 

Might pay to drop exhaust, bigger hole to look in or poke shop vac into?

 

turn it over a few times with the plug out will probably blow out of the spark plug hole. Not saying it won't get stuck in a valve think i would take a chance before pulling the head

 

Yeah, turn it upside down like a piggy bank and give it a good shake, it will go out eventually, lol!

 

:}) I think I better get back in the gym before I try that. I tried the vacuum with the hose through the spark plug holes, then I tried to pull the exhaust but I couldn't get the bottom part to break free, so then I pull the carburetor out to look in that way, but I couldn't see anything. Pulled off the intake boots off to get a little better look also, which I needed to pull them anyway because theyre cracked and whoever installed them had the seal blocking part of the passage on one of them. Any tips for the stuck bottom part of the exhaust before I through the bike on my shoulder upside down and start jumping up and down?

 

Wire wrapped with fly paper through plug hole...call me crazy!

 

2 Q-Tips taped together.
Q-Tips taped to Coat Hanger Wire.
Dip Q-Tip ends in High-Tack Spray-a-Gasket.
Let get tacky.
Jack Piston to height for "Good fishing".
Good luck!

 

Absolute Genius right there!

 

Roll the engine until both valves are closed and shoot compressed air through the plug hole. It should come out.

 

As Rick would say...choose any prize of the top shelf! :idea:

 

cool. thanks mlew. That'll give me something else to try tomorrow after work. I did finally get the exhaust off and I cant see anything in there. I tried fishing for it with the hanger with a bunch of inverted duct tape zip tied to a small loop I made (I didn't have any fly paper......or spray a gasket). So now with carbs boots and exhaust off I'd imagine I should see it blow out somewhere. Thanks.


LOL...... you guys may not understand if you've never seen the show, but you guys could make the challenges for that show Minute to Win It. : )

 

when i helicoiled my spark plug hole... i used cotton rope soaked in motorcycle oil. Try something similar with spray adhesive maybe?

or try one of these. I use this often (my fat fingers drop small screws into small spaces constantly.

http://www.harborfreight.com/24-inch-2- ... 94162.html

 

thanks guys for all the help, hopefully when I get off work I can get out. My next question is, now that I have my clearances in check, and i get everything back together, I planning to sync my carbs with a home-made synchronizer. I have my mason jars and Im planning to buy the necessary hoses when I get off work. Does anyone know what size hose fits on those vacuum (no sure what theyre called but on top of intake boots)?

 

Be very carefully at this point you are risking a bent valve.
Nylon in wire ties is very, very tough.

Do all movement slow and with the other plugs out. Cover them with a rag. Any sudden resistance means STOP and find out why.

You must fish it out and Know you got it out.

I have been down this road. Your only port hole to see is the plug hole , so don't waste time with the exhaust that needs penetrating oil and a torch.

And don't roll the engine so fast it gets smashed into the head or piston. It will do your crank or bearings no good.

Tilt the engine to one side to narrow the playing field. Then sticky or suck it out. Or take off the head.

Michael

 

They are called vacuum ports. The drawing I referred to to make my own sync tool says 1/4 inch interior diameter vinyl hose.

 

here is what i would do take the plug out and lean the bike on its side (if the engine is still on the bike) take your shop vac and put it right over the plug hole. but first cover the shop vac end with your wifes nylons or a thin sock (or other thin breathable fabric, a dryer sheet and rubber band would work too) then try to suck that piece out of the engine, having the nylon over the vac hose will catch the piece making your 100% certain that the piece is removed. every once in a while is sucking it out doesnt seem to be working, use an air compressor and blow some air in there to move the piece around and repeat with the suction. tipping the bike on its side will help fight gravity, its easier to suck something up a bit of a slope; than up 6 inches of nothing.

 

Don't worry about it. If it is indeed in the combustion chamber, when you start the engine up, it will melt down. If it gets under the intake seat, it will start running rough, if at all, on that cylinder. You can the take off the carbs and manifold, put the vacuum hose up against the port and open the valve.
If it gets under the exhaust valve, it won't last long, what with the hot gases going by.
I've seen small metal washer out of carbs that have gone through an engine, and come out the tail pipe. Noisy, but not disasterous.
CZ

 

"I've seen small metal washer out of carbs that have gone through an engine, and come out the tail pipe. Noisy, but not disasterous."

Man, the thought of that just made me hurl a bit!

 

It IS something to worry about.

These are INTERFERENCE MOTORS. If the piston goes across TDC with either valve open, it will hit the valve. Trying to start this motor (or even rolling it over any faster than VERY SLOWLY, BY HAND, "feeling" for resistance) could quickly bend a valve before any combustion heat would be generated.

You can't just fire the motor and hope it "blows out." The chance for damage is too great.

 

i'd like to know what kind of sissy ziptie was used that could be broken off by closing a valve on it

 

I'm not sure what kind of sissy zipties they are. I had them overlapped (one ziptie sticking past the other about 3/16 of an inch and duct taped together. They were both bent into a 'J'. They both broke, but the shorter one was still stuck to the duct tape. The worst part about the whole thing is I'm not 100% sure which plug hole its in because I didn't notice it missing till I was replacing the next to last valve shim.

I've done everything on this thread suggested to remove it except fly paper (don't have any), start the bike (fitz scared me straight, but I was getting ready to) and pull the head. Guess I'm gonna have to do the latter. sigh......... I'll do a search on pulling the head. Any suggested links would be appreciated. Thanks guys

 

well then you can't be sure it's even in the engine, it could be anywhere.

 

yeah, I suppose. I certainly can't find in there or anywhere. I even had the bike almost laying all the way over with vacuum on the port with all the valves in up and down position, with my wife's nylon on the hose. Nothing. I don't know. Maybe I should just try it and see. Is there any way it could have gotten under or wedged on the side of the piston? I just don't want to tear it up. Im gonna go check my garage floor again to see if its laying around. Check back in a little.

 

well if your gunna take off the head, might as well do some cleaning while your in there, lap the valves and repalce the head gasket (as it will most likely get wrecked when you pull the head off). find a nice gasket kit, i got mine off ebay for abour $90 and it comes with basically everything, alot cheaper than just buying a head gasket.

 

:idea:

I have a telescopic magnet with a universal joint on the end. You can find them at auto part stores. Or stick a strong magnet on the handle end of a thin screwdriver shank and go in through the plug hole with the tip.

Oops sorry I misunderstood, thought you were talking about one of those twist ties that comes on a loaf of bread with the wire inside.

Good luck!

 

I have a carb throttle blade screw that worked out and into the cylinder. I can't seem to find and don't know if it is there still. If you come up with something let me know I am sorta screwed right now.

Good Luck

 

search ebay for "usb inspection camera", then search youtube

 

Threadbrewer, a guy I work with who used to work on motorcycles albeit not any xj's says he has found several washers from spark plugs and miscellaneous other things that came from the cylinder in the exhaust. Not saying that its your case or that he wasn't maybe exaggerating, but it sounds like yours most likely occurred while running so it sounds plausible to me. In my case I have spent 2 or 3 days on nothing but coming up with new and exciting ways to get a blasted piece of plastic to no avail. The camera thing is a cool idea. Im gonna see if anybody sells em locally first, but I'll probably end up ordering one off ebay.

 

I've looked at bore scopes but they are spendy. It was running and I have pulled the exhaust to no avail. I can see where the screw banged around in the top of the piston and what cylinder walls I can see still have the honing lines in them. Valves seem fine but I just want to be sure. How about i take apart my old cell phone and see if I can use its camera????? Hmmmmm

 

I would not want to argue with you, but if the piece of plastic got caught under the valve seat, I can almost guarantee that it will be flat, and that is what, .070-.080 thick?
If you look at the valves, you will see that they have to be out a bit further than that to hang up on each other, or the piston.
Just my thoughts on it. CZ

 

I don't know personally either way. I've done quite a bit of researching ever since fitz said the "interference motor", and it looks like that means that the piston and valve most certainly use the same space and different times, but I can't find anything specifically about my bike that says how much of that space is shared. I did try to bump the starter today without the gas tank on just to see if it sounded funny, but the only thing that happened was the oil light came on, but the started didn't even whisper screw you to me. I know the battery is completely charged and it was starting just fine before, so I may have a new adventure ahead of me.

 

If you're 100% sure the piece of zip-tie is still in the combustion chamber DON'T DO THAT.

INTERFERENCE MOTOR does indeed mean the piston and valves occupy the same space at different times; and I can't tell you how much space there is available at TDC. It's not something you want to find out the hard way.

The oil light coming on when you mash the starter button means the safety circuit is deployed. The bike thinks it's in gear with the sidestand down. Sidestand switch, neutral switch, wiring...

 

Here is a fairly accurate discription of valve overlap,

http://www.cdxetextbook.com/engines/comp/vlves/valvetimingdiagram.html

If you look at it, you will notice that at TDC on the exhaust stroke, both the intake and exhaust valves are open, and the piston is at its uppermost excursion.
Since Mother Yamaha is parsimonious with it's cam data, it would be difficult to say exactly HOW far they are open, but a man with a dial indicator and a degree wheel could soon find out.
My point is that the thickness of a ty wrap is not likely to be a catastrophic experience for the engine.
And the "not likely" is my way of saying, it is up to you to weigh the hassle against the outcome.
Personally, I would crank it up. The worst case is that you are out the cost of a valve and possibly a piston, over and above the cost of gaskets and labor, which you would have to do anyway. And if it cleans out, you've saved time and money.
Are you a gambler? :?:

CZ

 

valve overlap and interference engines are apples and oranges.
overlap is both valves open at the same time anywhere in the piston stroke.
a interference engine is one that the piston and valve occupy the same space at different times.
a L head Briggs can have valve overlap

 

K got mine out when I blew compressed air through the intake and had the vacuum with nylon rig over the spark plug hole, it wasn't as big as I thought it was though. Just the triangle tip. Thanks for helping me through guys.

P.S. Threadbrewer, I hope you have as much "luck, (if you call 32 hours combustion chamber fishing lucky) as I did. I would probably try little magnets tied to something. I wonder what the probability is that it could have just shot out the exhaust? At least you know which one you to be looking in. Let me know how the camera thing works out.

 

CAMSHAFT DATA:

XJ550 Maxim:

Intake Lift: 6.80mm
Exhaust Lift: 6.80mm

Duration: not given

Overlap: not given


XJ550 Seca:

Intake Lift: 7.80mm
Exhaust Lift: 7.10mm

Duration: not given

Overlap: not given


XJ650 all models except Turbo:

Intake Lift: 8.50mm
Exhaust Lift: 7.80mm

Duration:
Intake opens 34-degrees BTDC
Intake closes 58-degrees ABDC

Exhaust opens 66-degrees BBDC
Exhaust closes 26-degrees ATDC

Overlap: 60-degrees


XJ650 Turbo:

Intake Lift: 8.50mm
Exhaust Lift: 7.80mm

Duration:
Intake opens 28-degrees BTDC
Intake closes 48-degrees ABDC

Exhaust opens 53-degrees BBDC
Exhaust closes 23-degrees ATDC

Overlap: 51-degrees


XJ700 non-X models:

Intake Lift: 8.80mm
Exhaust Lift: 8.30mm

Duration: not given

Overlap: not given


XJ700-X models:

Intake Lift: 7.50 - 7.70mm
Exhaust Lift: 7.35 - 7.55mm

Duration: not given

Overlap: not given


1981-83 XJ750 models:

Intake Lift: 8.80mm
Exhaust Lift: 7.80mm

Duration: not given

Overlap: not given


XJ750RL models:

Intake Lift: 8.80mm
Exhaust Lift: 8.30mm

Duration:
Intake opens 38-degrees BTDC
Intake closes 58-degrees ABDC

Exhaust opens 56-degrees BBDC
Exhaust closes 26-degrees ATDC

Overlap: 74-degrees


XJ900RK and RL models:

Intake Lift: 8.75mm
Exhaust Lift: 8.25mm

Duration:
Intake opens 38-degrees BTDC
Intake closes 58-degrees ABDC

Exhaust opens 66-degrees BBDC
Exhaust closes 26-degrees ATDC

Overlap: 64-degrees


XJ1100 models:

Intake Lift: 8.80mm
Exhaust Lift: 8.80mm

Duration: not given

Overlap: not given

 

If you read and think about what I wrote, you will see that I was making the point that when the piston is at TDC on the exhaust stroke, BOTH valves are open to a degree.
Each Exhaust stroke, the same thing happens. They are all sharing space in the combustion chamber. All at the same time.
What most people, who do not take the time to think this through, assume, is that if the valve is open, and the piston is up, bad news. The piston is timed to occupy space that the FULLY OPENED valve occupied a fraction of a second ago. That means that if the valve HANGS fully open, the piston will hit it. Most of the occurrences you hear about are a timing BELT breaking, and one or more poor valves are left pushed open while the piston continues to travel. Sometimes the cam/s stop at a point that none of the valves are open far enough to get hit. Luck of the break.
Think about a dance line of chorus girls. As long as each does her kicks at the proper time, all goes well. If one gets her timing screwed up, 8O
Our bikes use a chain to keep everything in time, and they are less susceptible to breakage than a belt.
They do wear (elongate), and if not re tensioned, can jump a tooth, but until they jump more than one tooth, they will usually still operate without catastrophic effects.
However, as pilot in charge, you make the final decision as to run or not.

CZ

 

Great, now we can quit discussing methodology.
Aren't you glad you didn't take the head off? :wink:

CZ

 

Note to self: don't use the cheapo wire tie, tie wrap, zip tie things when doing a valve job...

 

Right!!!!!! At least make sure you know what the h#$@ you're doing before you start. : )