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anyone have a tip here on how to loosen the camshaft bolt without damaging anything if you dont have power tools?
I followed one of the guys said here and just put the timing belt and rotated the engine to cam + crank TDC. lined up perfect.
I did do the compression test for the 1st cylinder. it was cranking real slow and the numbers were low but i suspected the battery was low cause the car hadnt been drive in a month. i got impatient at that point and started the car. ran fine.
finally, a few weeks ago i got the job done (including valve adjustment). i was a little worried because, at warm engine after coming to back to idle (e.g. moving to neutral at stop sign), it started going down to 500 and picking up back to 700 (almost like engine dying or coughin). i did the idle relearn by letting the car idle until the fans started twice and adding 5 mins to idle time and the problem went away.
one thing that worries me is that at around 750 rpm, i have mild steering wheel vibration despite (i think) having the balancer belt aligned accompanied by some kind of pulsating that i can feel throughout the car (like if i have no hands on the steering wheel, i can feel slow but mild rhythmic pulsation through the pedals). i hear that could due to engine imbalance.
so maybe i did do some damage by loosening the cam with the timing belt on. the question really is what that sound was. sounded like a “twang”.
but the car drives just fine. i still have slight bucking at low gear/low speed acceleration and when i release the accelerator pedal at low speed/gears but this was present before the TB change as well.
thanks for everyone help here.
thanks. that answers my questions.
in terms of keeping this car for another 5 years, is using the old cam advisable? i was wondering if this matters only if we are talking about super long term reliablity.
i do have the cam from the same junked car so i could swap it out but i want to understand if thats absolutely necessary.
thanks again.
also whats the logic behind cam wear/rocker arm wear and a valve adjustment staying put just until the engine is rotated?
also given that, despite the wear, the clearance is still within spec, should i bother fixing this problem or or are there other consequence?
hi college man,
thanks for the reply. i removed the rocker arms and camshaft. i dont have the tools to measure both of them ( i do have the honda service manual).
from a simple visual check, i see that one of the rocker arm rollers (the primary intake rocker arm doesnt really have a roller like the vtec and secondary rocker arm, its just a semicircle) has chipped edge but i dont know how engines work and i dont get how that small chip would logically cause a loose valve.
i am thinking that i should just goto a junkyard and get a cam + rocker arm(s). i had ignored an oil leak from the camshaft seal for 5 years that, im guessing, caused accelerated wear on the cam/rocker arms. or that i bought the car at 137k and didnt know anything about cars and it probably didnt have valve adjustments its entire life (now at 182x).
do u have any tips on what i should be looking for in terms of wear?
or a website where i can read about this topic?
thanks college man.
ummm…i could try another used pulley from the junkyard ($20) but i dont see anything wrong with the current one. the rubber is not coming off at all.
hi everyone,
had some time yesterday to touch the car again.
i just removed the plugs and rotated the engine and everything lines up perfectly with no binding (as far as i can tell).
is there anyway i could have messed sth up and it still lines up like it does?
any way to check via looking at rocker arm movement while rotating the engine?
i have some tmrw to do a compression test. safe?
thanks guys.
thats kind of what i was thinking as the safest method.
by valves backed off, do you simply mean loosening the valve adjusting nuts and tappet/screws OR removing the rocker arms altogether? im guessing with valves backed off,i dont need to remove the cam and realign but rather just move the sprocket to align it?
im learning a lot through the forums guys. thanks.
I know rotating the crank 360 will get the cam to tdc at this point but if there is something wrong, wouldnt that just make it worse?
also, i thought rotating 360 the opposite direction would cause damage?
there is an interesting discussion here: http://honda-tech.com/acura-integra-6/my-timing-belt-broke-how-do-i-find-tdc-2746384/ (towards the end of the page) about valvesprings tighetening feeling like pistons hitting valves. From the sound i heard, it was more of the thick springs geting really taut (possibly valvesprings?). how do i remedy the situation if it was simply the valvesprings tightening?
“Your crank fully rotates TWICE for every full rotation of your cam. That is because the piston is at TDC once at the end of compression stroke and again at the end of exhaust stroke. It is perfectly NORMAL for the crank to be at TDC and your cam be 180 degrees off. That means #1 is on exhaust stroke instead of compression stroke. For timing the engine, it needs to be at TDC on compression stroke, because the plug fires at the end of compression stroke initiating the power stroke.”
i know that.
what i am asking is how i can get both to tdc before i continue with the TB job. here are the options:
1) WRONG:::leave TB on and tension on and rotate to make crank and cam at TDC. (this could make the current wrong alignment create further damage [not sure about this as i dont see TB damage and at max a tooth or two off at cam]).
2) WRONG::: remove TB and rotate cam to TDC (wrong for obvious reasons)
3) RIGHT??? make sure crank is tdc. remove TB, rocker arm, camshaft. re position cam to TDC. contiue with normal TB job.
thanks again guys.
thanks again.
i understood everything u are trying to say. big f(#@ up. i know. and will do as you instructed so when i get off work tmrw.
BUT my crank is at tdc but my cam is 180 degrees off. so u are saying with the timing belt off, rocker arm still in place, i can simply the rotate the cam to TDC without damaging anything more? the instructions say to put both cam/crank at tdc before removing the timing belt.
i dont understand engines and shouldnt be doing the job but doesnt it make more sense to remove the rocker arms and camshaft and put the cam to tdc, then go on with the normal timing belt replacement procedure?
sorry buddy for all the trouble. i appreciate your help in not only doing the job but understanding why. thanks.
also what is the 4 stroke rule?
I also got lost in this sentence due to the lack of full stops and commas. “If you are unsure about cam position, but have full confidence your number 1 piston is at TDC, with the rockers backed off you can rotate the cam and make sure you have the correct positioning following 4 stroke rules when there is no cam sprocket on and no valve spring pressure it spins freely.”
did you mean that with crank at tdc and rockers backed off, you can rotate the cam without any damage? why the “with not cam sprocket on”? how can u rotate the cam without the sprocket on?
sooooooooooo….
just to make sure i got this (combined understanding what all of you are saying):
1) back off rocker arms (i am guessing that means either remove the rocker arm assembly, which is easy, or loosen the tappet adjusting screws)
2) remove timing belt tension
3) align the cam back (if the rocker arms are off, i am guessing the cam can be rotated without moving the valves or causing any damage?)
4) put everything else back
5) remove spark plugs
6) rotate engine via crankshaft to see if there is any binding?thanks guys. i am positive crank is at tdc and that the cam is close or at cylinder 3 (i.e. point to the floor). i am still not clear on how to move cam back to position without damaging anything (unless what i said above is accurate).
also, can i loosen all tappet adjusting nuts (to make reinstallation of rocker arms easier) without moving the cam/crank to the respective cylinders?
oh man. this etcg forum is alive and kicking. awesome.
some clarification: by back off rockers, you are suggesting loosing the adjusting nut as you do for valve adjustments?
thisisbuod, what do you mean by put it back together. i didnt remove the timing belt or tension so all i need to do to get it back as it was (except the cam position if that got messed up) is to put in and tighen the crank pulley bolt.
if the cam position did get messed up, dont i need to align it back before i try rotating the engine? and how do i align the cam back without moving the crank?
thanks guys. i have work today but tmrw i should have time off to check things out. when i do, if the cam/crank seemed perfectly aligned as it is, does that mean i didnt do any damage?
and the sprocket removal was because the main reason for this job was to change the cam seal which has been leaking for 5 years. i saw that etcg in his vmanual just had the tension on and used an impact. i lost my head and got dumb towards the end of the day and thought why wouldnt just using the breaker bar do the same (STUPID!). oh well. i just thought “ok. if the cam moves while trying to remove the bolt, the crank would do the same due to the TB being in tension just like how the PS belt can be used to turn the engine” maybe not.
when i get back to my carport tmrw, i will also post a pic of what a “slightly” wobbling crank can do to a lower cover and what a 5 year oil leak into the TB area does.
i dont have access to do a leakdown test (no compressor).
i can rent a compression tool from o reily.
either way, what i am thinking is to put the damper and bolt back, tighten it a little bit, remove spark plugs, gear in neutral and try to manually spin crankshaft and see how it feels (i have had to do this before for valve adjustment) and whether both cam/crank line up at tdc.
is that safe?
also, i hear compression tests are supposed to be done with a warm engine and i dont want to start the car to risk further damage? or can a cold compression test say sth enough AND not do anymore damage?
didnt have time to do much expect check the rocker arms today. given the position of the cam (pointing down), cylinder 3 rocker arms were supposed to be loose enough to move a little by hand (like when doing valve adjustments) but the exhaust side was tight and i cudnt get it to move by hand at all. what does that mean?
also, what does backing off ALL rocker arms mean? i have removed rocker arms before…
if i had to replace the valves, i am willing to learn. i heard u can simply unbolt the 5 or so intake manifold bolts for the intake side to remove the cylinder head without dis-assembling fuel lines/etc. is that true?
thanks a lot guys.