HELP!!! Valve clearances

[trigger181]

First off, this site has been great, lots of info and easy to understand. I have an 89 GSX750F. I just did my valve clearances and once it is at operating temp. I have a very noticable rattle, much more so then before, from the engine. When I checked the clearances before I adjusted they were all way tighter than the specs. I adjusted in the order.....I think. I did them from 1-4 being from the left to right and did them in the order stated in the manual. I couldn't find which was which in the manual but I assumed the intake valves were where the carbs come in and the exhuast being at the front of the engine at the exhaust pipes...is that correct?? The manual said to set the intakes between .10 and .15 so I set it at .12 The exhaust said between .18 and .23 for clearance and I set them to .20. The engine has about 60,000km and to my knowledge it is the first time the valve's have been done. Does anyone have suggestions as to what the clearance should be set at or any other suggestions.

Any help would be great.

Thanks

Trevor

[Newbie2it]

Correct, Intake is where the carbs are. As for the specs.. Middle of the roads ok. As for the rattle, Can you narrow it down some, with a stethascope or a peice of wood? Maybe something else is loose and rattling.

[dnargsiefil]

Did you check the cam chain tentioner? CP has deals on the spring and gasket. I have the same bike and replaced the spring with the valve adjustment. I have only 15k on my bike and the spring was about 3/4 inch shorter than the new one. Don;t knwo if this could cause the noice, but since this is the first valve adjustment (scheduled maintenance I think calls for it about every 15k), maybe this one has never been replaced as well.

[trigger181]

thanks for all the hlep. I took the valve cover off and realized my problem....the nut on the adjuster screw for the #1 exhaust valve is how how missing and the adjuster screw had loosened right off. Now I have to try and somehow find the nut that came off. Anyone have any suggestions? I will be checking the oil to see if it worked it's way down and out when I drained the oil. Also, since it's such a small nut if I can't find it. is it a problem to just leave it and hold it gets chewed up and spit out in the oil?

[Court93kat]

You should try to find it. No matter how small, a hardened steel nut can wreak havoc on aluminum engine pieces.

[olds455]

my matinence manual shows the cold valve clearances. So your valve clearances are probaly to loose if you did it hot. I set mine with the cold engine and its pretty quiet. I know my race car was suppose to have the lash set hot but this is my first bike.

disregard, I see you lost the nut, good luck

[Newbie2it]

Chances are, that if you are totally sure you searched every nook and cranny of the valve cover inners (Do a total thorough look see. Look everywhere, between springs ect.)

If you thoroughly searched and have come to the conclusion that the nut is simply gone. Then count your blessings, Because it made the fall past the cam chain without getting caught in the gears.

But make damn sure its not on the top someplace. There are 4 valley covers under the cams that are held in place with bolts. If it went into there, its ok, Its not going anyplace. If it made its journey though the cam chain journal, then its sitting in your oil pan, You're safe there too, But wont know for sure till you drop the oil pan.

I'd say, pull the pan as a first step, if its there, your golden. If not, you need to start looking. Dont run the motor at that point till you find it. Look inside the valve springs, Under the rocker arm rod, Cams ect. The pan gasket is reusable so no biggie there, sans dropping the exhaust, But peice of mind is worth more. Plus you'll have the nut you need back. And if its in the pan.. You'd better knock on some wood or whatever, cause if it got caught in the gear, it would have done some major damage.

[The CyberPoet]

You'll need to drop the oil pan and look for the nut -- it may also be sitting in the oil pump pick-up screen, which is where such things tend to end up (after the oil pan is off, look up at the oil pump & you'll see a mesh screen in the way).

If you don't find it in the oil pan, things get tougher...

The other thing to do is use a magnetic pick-up down every crevice you find at the top of the engine, in the hope of getting it; it's possibly in the main oil gallery (which is not the oil pan), or even down in a cylinder after falling through a valve (doubtful, but easy enough to yank the plugs and stick the magnetic probe in each hole & move it around in a pattern to cover the entire cylinder contents).

As noted above, engine clearances need to be done cold. I hope you also didn't confuse the measurements in terms of mm vs inches -- the numbers you posted were specifically metric.

Cheers,
=-= The CyberPoet

[trigger181]

once again thanks for all the info. I did do the clearances when it was cold after sitting for a day. I will have a closer look for the nut up top and take the oil pan off and hopefully find it there.

Thanks again

[Newbie2it]

CP, Kinda curious, but how would a nut mitigate threw the valve seals to enter a cylinder?

In this case, I would say not likely at all.

[The CyberPoet]

If you're talking about the valve guide seals, breaking them (or the valve itself) while bouncing around under driven force in a running engine. Not likely, but I've seen some damn unlikely stuff happen over the years


Cheers,
=-= The CyberPoet

[Newbie2it]

Ok, Thats why I questioned this statment you made LOL

(Quote)
or even down in a cylinder after falling through a valve (doubtful, but easy enough to yank the plugs and stick the magnetic probe in each hole & move it around in a pattern to cover the entire cylinder contents).
(end quote)

Sounded like you were telling him it might have fallen into the cylinder which isnt possible unless it broke the valve seal or the stem, in either cause, he'd have more worries then just a lost nut LOL

[The CyberPoet]

Sounded like you were telling him it might have fallen into the cylinder which isnt possible unless it broke the valve seal or the stem, in either cause, he'd have more worries then just a lost nut LOL

The lost nut could mean damages to the springs, valve stem, valve, etc. Think of the moving parts as playing volley ball and the nut is the ball.

IF he can't find it anywhere else, that's the place to look... because it's always where you can't imagine it'd be I did put it on the end of the list because it's the least probable.

Cheers,
=-= The CyberPoet

[Newbie2it]

Exactly why I said this in a previous post.
"Quote"
Look inside the valve springs, Under the rocker arm rod, Cams ect. The pan gasket is reusable so no biggie there, sans dropping the exhaust, But piece of mind is worth more. Plus you'll have the nut you need back.
"End quote"

Its also why in the same post, I said not to run the motor till he finds it. Damage is a real possibility hence why I also said to take due care in looking everywhere.

Its not possible for a piece in the upper valve train to directly enter the cylinder. Hence my questioning your statement originally. But its all good. Either way.. His loose nuts not in the cylinder. So no need to break out the magnet and go searching the top of the cylinder.

[kenn1320]

It will not be in the cyl bores. Also, since you had this problem, I suggest going thru the procedure again. You might have missed another one. It happens, dont take it personally. However I would not start that engine, till I found that missing nut. As pointed out in earlier post, if it gets into moving parts, it can really tear stuff up. Good luck with your search.
Ken

ps. If you dont know intake from exhaust on an engine, adjusting the valves might be something you hold off on, till you have a friend that has done it give you a hand the first time. Your past that, this comment is for others that are thinking of trying this.