engine sounds different
#1
11-23-2007, 11:40 PM
Unregistered
Posts: n/a
engine sounds different
i just had a new timing belt, balancer belt, water pump, and 3 oil seals (cam, oil pump, crank) installed by honda (cost was 800)
92 accord ex 2.2 cb7
since this, i've notice the engine sounds different. at idle, it has an audible whine, that seems to go away when the revs go up.. it wan;t there befor all the the work. is there some 'settling' time needed for any of these parts to quiet down, or should i take it back to the shop ?
92 accord ex 2.2 cb7
since this, i've notice the engine sounds different. at idle, it has an audible whine, that seems to go away when the revs go up.. it wan;t there befor all the the work. is there some 'settling' time needed for any of these parts to quiet down, or should i take it back to the shop ?
#2
11-24-2007, 01:02 AM
RE: engine sounds different
It really depends on the whine. It could be your timing belt rubbing against a cover.
Don't know how your Honda's engine is mounted but on mine you have to loosen up one of the engine mounts to take off the timing belt. If this is true on yours then they may not have goofed on the mount.
Can you push on the motor a little and see if the noise goes away. Don't burn yourself.
Don't know how your Honda's engine is mounted but on mine you have to loosen up one of the engine mounts to take off the timing belt. If this is true on yours then they may not have goofed on the mount.
Can you push on the motor a little and see if the noise goes away. Don't burn yourself.
#3
11-24-2007, 04:33 PM
RE: engine sounds different
I have a similar issue with my CB7. Changed the timing and counter balance shaft belts andimmediately got a sort of 'buzzing whine' at certain rpm. It'sslight, and not audible at idle or higher rpm, mostly on light throttle or on overun at low to medium rpm. When I open the bonnet (hood for Yanks) give it a rev and try to hear it I barely can, but it's more noticable from inside the car when driving.
I don't know what's causing it, but it's been there for quite a while now with no change, and nothing has broken or otherwise gone wrong and the motor performs fine (though it is a minor irritation). It sounds a bit like it could be a vibrating heat shield or similar, but I'm 99% sure it isn't and is directly related to the timing belt.
I have a theory, right or wrong; The old timing belt and timing sprockets / gears are slightly worn, but are 'run-in' to each other so quiet. When a new timing belt is installed, the belt is unworn and has sharp edges on the belt teeth, and these might make a slight sound as they come into contact with the slightly worn teeth on the sprockets???
Other than this, it might be that the idler pulley bearing is slightly worn (I know, I should have replaced it, but I was broke at the time!), and when the new belt was installed it was installed at a slghtly different tension, and this might cause the pulley bearing to make noise at certain rpm whereas it didn't previously?? Could it be the belt pre-tensioning spring vibrating? I don't really know.
I don't know what's causing it, but it's been there for quite a while now with no change, and nothing has broken or otherwise gone wrong and the motor performs fine (though it is a minor irritation). It sounds a bit like it could be a vibrating heat shield or similar, but I'm 99% sure it isn't and is directly related to the timing belt.
I have a theory, right or wrong; The old timing belt and timing sprockets / gears are slightly worn, but are 'run-in' to each other so quiet. When a new timing belt is installed, the belt is unworn and has sharp edges on the belt teeth, and these might make a slight sound as they come into contact with the slightly worn teeth on the sprockets???
Other than this, it might be that the idler pulley bearing is slightly worn (I know, I should have replaced it, but I was broke at the time!), and when the new belt was installed it was installed at a slghtly different tension, and this might cause the pulley bearing to make noise at certain rpm whereas it didn't previously?? Could it be the belt pre-tensioning spring vibrating? I don't really know.
#4
11-24-2007, 05:50 PM
Been Around A Long Time Member
Join Date: Dec 2005
Location: In The Desert ( Sahara ? )
Posts: 4,754
RE: engine sounds different
have them recheck the timing belt + balancer belt adjustments ,, if a bit too tight it will make a whining noise
#5
11-25-2007, 07:30 AM
Unregistered
Posts: n/a
RE: engine sounds different
thks folks for the ideas.
1. it appears the power steering fluid is down a bit, so it might be the pump whining - I'm going to take the belt off and see if the noise goes away..
2. i will put new fluid in on Monday (my local Honda mart isn't open on weekends), and all the manuals, labels etc. say to use only Honda power steering fluid at the risk of great peril if I do not.
1. it appears the power steering fluid is down a bit, so it might be the pump whining - I'm going to take the belt off and see if the noise goes away..
2. i will put new fluid in on Monday (my local Honda mart isn't open on weekends), and all the manuals, labels etc. say to use only Honda power steering fluid at the risk of great peril if I do not.
#6
11-26-2007, 09:12 AM
Unregistered
Posts: n/a
RE: engine sounds different
Fellow CB7 owners, if you have powering steering pump on your Accord (I thought they all did?, but maybe not), could you
start up your engine, and grab the main hose that goes from pump towards the back of the engine compartment, and tell
me if it is vibrating ? Mine does, not sure if this is the cause of my new 'engine sound'..
start up your engine, and grab the main hose that goes from pump towards the back of the engine compartment, and tell
me if it is vibrating ? Mine does, not sure if this is the cause of my new 'engine sound'..
#7
11-26-2007, 02:42 PM
RE: engine sounds different
thks folks for the ideas.
1. it appears the power steering fluid is down a bit, so it might be the pump whining - I'm going to take the belt off and see if the noise goes away..
Maybe, but if it’s only down a bit I doubt the pump would complain. You might be on the right track though, with luck!
Thinking about this, what is a more likely possibility is that one or both auxiliary drive belts may have been over-tightened? Alternators can easily make a whining noise if the belt is too tight, the AC and PS conceivably might. The ‘flat’ belts used on these are typically run fairly tight (tighter than the ‘V’ belts that used to be commonly used), but you only need them to be tight enough that they don’t slip (and squeal).
I’d experimentally remove both these belts to see what happens. Keep your fingers crossed!
2. i will put new fluid in on Monday (my local Honda mart isn't open on weekends), and all the manuals, labels etc. say to use only Honda
power steering fluid at the risk of great peril if I do not.
Only Honda PS fluid. My understanding is that other fluids may or may not be compatible with seals etc (?). The Honda fluid is cheap enough, no need to risk an experiment!
3. please tell me adjustments to the timing belt/balancer belt can be made without taking the crank pully and the two covers off !
I could tell you this just to make you feel better, but unfortunately I’d be lying!
To gain decent access to the adjuster (through the wheel arch) I think you’ll also need to lower the engine which involves loosening the two right side front sub-frame bolts and actually removing the two on the left side (so sub-frame and engine can be lowered on a jack). The left side engine mount also needs to be removed.
I think
the manual says the tension adjustment bolt should be torqued to 45NM ? does the torque setting correspond to the tension setting,
or is the 45NM (33ft lb) just what keeps the tensioner in place ? (ie. if I torque this bolt higher, will it make the belt tighter ?)
No, the torque setting has nothing to do with the tension of the cam and balance shaft belts. It only has to do with ensuring the adjuster can’t slip in service and doesn’t break when tightening the nut. It’s not a critical torque, any competent mechanic should be able to tighten it by feel. If you have any doubts you can’t go wrong using a torque wrench!
On Hondas these toothed belts are typically run with little tension (significantly more on some other cars though), only enough so that there is no slack in the belt run (i.e. there is some tension, but only slight). Rely on the adjuster spring to set the correct tension, but you do need to ensure that there is no slack in the belt in the longer run between the cam and crank pulleys (the part of the belt run toward the front of the engine). If slack exists here the spring isn’t strong enough to pull it out because of the resistance in the valve springs. With the belt etc in place, take up any slack here by rotating the cam pulley clockwise by hand.
I like to then firmly push against the adjuster itself to fully remove any slack elsewhere in the belt run, but before you tighten the adjuster release this pressure and allow the belt to ‘relax’. To ensure that the adjuster doesn’t move as you tighten the nut, you can very lightly rest a finger on the adjuster as you tighten it.
Keep in mind that if it’s a new belt it ‘wants’ to be in the shape it was in when in the box (i.e. coiled up), and it will to some degree resist being ‘forced’ into its new shape as wrapped around the pulleys, and this could manifest as the belt being a little too loose if you’re not careful. I’d run the engine for a little while end then re-check the tension.
1. it appears the power steering fluid is down a bit, so it might be the pump whining - I'm going to take the belt off and see if the noise goes away..
Maybe, but if it’s only down a bit I doubt the pump would complain. You might be on the right track though, with luck!
Thinking about this, what is a more likely possibility is that one or both auxiliary drive belts may have been over-tightened? Alternators can easily make a whining noise if the belt is too tight, the AC and PS conceivably might. The ‘flat’ belts used on these are typically run fairly tight (tighter than the ‘V’ belts that used to be commonly used), but you only need them to be tight enough that they don’t slip (and squeal).
I’d experimentally remove both these belts to see what happens. Keep your fingers crossed!
2. i will put new fluid in on Monday (my local Honda mart isn't open on weekends), and all the manuals, labels etc. say to use only Honda
power steering fluid at the risk of great peril if I do not.
Only Honda PS fluid. My understanding is that other fluids may or may not be compatible with seals etc (?). The Honda fluid is cheap enough, no need to risk an experiment!
3. please tell me adjustments to the timing belt/balancer belt can be made without taking the crank pully and the two covers off !
I could tell you this just to make you feel better, but unfortunately I’d be lying!
To gain decent access to the adjuster (through the wheel arch) I think you’ll also need to lower the engine which involves loosening the two right side front sub-frame bolts and actually removing the two on the left side (so sub-frame and engine can be lowered on a jack). The left side engine mount also needs to be removed.
I think
the manual says the tension adjustment bolt should be torqued to 45NM ? does the torque setting correspond to the tension setting,
or is the 45NM (33ft lb) just what keeps the tensioner in place ? (ie. if I torque this bolt higher, will it make the belt tighter ?)
No, the torque setting has nothing to do with the tension of the cam and balance shaft belts. It only has to do with ensuring the adjuster can’t slip in service and doesn’t break when tightening the nut. It’s not a critical torque, any competent mechanic should be able to tighten it by feel. If you have any doubts you can’t go wrong using a torque wrench!
On Hondas these toothed belts are typically run with little tension (significantly more on some other cars though), only enough so that there is no slack in the belt run (i.e. there is some tension, but only slight). Rely on the adjuster spring to set the correct tension, but you do need to ensure that there is no slack in the belt in the longer run between the cam and crank pulleys (the part of the belt run toward the front of the engine). If slack exists here the spring isn’t strong enough to pull it out because of the resistance in the valve springs. With the belt etc in place, take up any slack here by rotating the cam pulley clockwise by hand.
I like to then firmly push against the adjuster itself to fully remove any slack elsewhere in the belt run, but before you tighten the adjuster release this pressure and allow the belt to ‘relax’. To ensure that the adjuster doesn’t move as you tighten the nut, you can very lightly rest a finger on the adjuster as you tighten it.
Keep in mind that if it’s a new belt it ‘wants’ to be in the shape it was in when in the box (i.e. coiled up), and it will to some degree resist being ‘forced’ into its new shape as wrapped around the pulleys, and this could manifest as the belt being a little too loose if you’re not careful. I’d run the engine for a little while end then re-check the tension.
Thread
Thread Starter
Forum
Replies
Last Post
Texas4Banger09
Headers, Intake, & Exhaust
5
06-01-2011 12:42 PM
hidehide
General Tech Help
6
11-10-2006 03:35 AM
