ok so im geting the top end ready for a valve adjustment....
and i have the motor at TDC - the "t" is lined up...
now when im lookin at the camshafts - no mater how many times i turned the engine and realined the "t" - the IN/EX marks on the cam sprockets were not lining up the way they should have - was off by 1/4 of the cam at any givin time....
so i TDC again, remove the tenisioner, remove exhuast and then intake camshafts, put camshafts in the correct position, check all timing/position marks, torque it all back down, double check all the marks - im good to go...
i go to spin the motor...going clockwise...not even a full rotaion....camshafts dont wanna move. this is when #4 exhuast lobes are about to start opening the thier valves.....
by all means, i should be able to spin that engine with no probs.... is it possable the camshaft holder is torqued too tight?? its set for 12 n/m... or is there something im over looking? :idunno:
i gotta make sure i cover everything...burned the camshafts on my 750 cuz they were too tight - thanks to a faulty toqure wrench which has sence been replaced.
You put your valve timing out by 90 degrees when you realigned the cams and your valves are hitting your pistons. If the engine was running before you started the work, the valve timing was correct and your documentation may have been wrong. Double check everything, take your clearance measurement when the lobe is pointed 180 degrees from the top of the valve. This will ensure that you are on the base circle of the lobe. Also make sure that you are following the torque procedure on the cams, this is usually from the inside out in a criss cross pattern, and dont just torque the first bolt all the way down, put them all in a little at a time so you dont put too much stress on the cam. If the timing is out and you torqued down a cylinder that the piston was at TDC and the cam was opening the valves, you may have already bent a valve in the process. Look for any abnormally wide tolerances when you are checking the valves.
will check everything...and post back up with some pics so you can see what i see, a lil later this morning - the manuel is a lil confusing about the position the lobes are spossed to be
The valve timing is either correct or it's not, so if it was running you need to put the cams back where they were orignally. If they were off by 90 degrees then there is no possible way the engine would run... the the exhaust valve would be open during the intake stroke and the intake valve would be open during the compression stroke etc.
any cylinder at tdc will either be on the end of the compression stroke or the end of the exhaust stroke. depending on which stroke, the cam lobes should either be pointing towards eachother but down about 45 degrees for the end of the exhaust stroke, or away from eachother up about 45 degrees for the compression stroke. You need to determine which stroke #3 is on and that will the the base for your valve timing. do not tighten the cams down unless one of these 2 cases is true. you can turn the motor with the valve train being out 180 degrees, but anything other than than that you greatly risk bending or breaking a valve. I'm not going to be on the computer for a while, take some pics and keep me posted, i'll be back later tonight.
Those are better pics
I don't have a manual for your bike but it _looks_ like you have the engine with 2 on TDC. Normally you want number 1 (opposite end to the sprockets) at TDC.
The marks on the crank trigger are in the wrong place.
The TDC mark is more likely the one next to the "T" I'd say. The non-sprocket end piston should then be at the top.
ok so i want to set the cams with #1 and 4 at TDC....
now the marks on the crank...the book says to do the timeing off the single slash mark lined up with the case cover.....so im not understanding how i have that wrong...
Well, as I say I don't have a manual for your engine but your crank is out and there's a big T on the crank trigger about where it should be
I don't know what that single mark is for though.
I agree, your crank is out 180 degrees, and #1 should be ready to fire at TDC with the cams in the position they are in. On my F4i timing is run off of both the cam position sensor and crank position sensor, i dont see one like what i have so look up the ignition system and see if it tells you how to identify which cylinder is getting ready to fire. #4 is beginning the intake stroke.
also, if you tightened it down like that, i'd bet you bent exhaust valves on number 3 unless it pushed the piston down cause when your crank is 180 degrees off, your cams are only 90 degrees off. Here's how you check the valve clearance now, turn the crank so the pistons are all at the same height (this will ensure that the valves will not hit the pistons), and then turn only the cams. when the lobe points directly away from the valve, check the clearance. Do not turn the crank while you have the cams tightened. Adjust your valves since you have to take the cams out anyway. Set your valve timing after you adjust everything.
I'm trying to decide if I want to do this job over the winter, or leave it for one more year.
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