andyz

2000 Accord LX Stock, 110,000 miles

There is a moderately loud valve noise at 1600-1900 RPM after changing the timing belt.

Any suggestions?

I could only describe it as chatter, flutter, or perhaps valve precession.

andyz

1a 1b 2a 2b 3a 3b 4a 4b
I 8 9 9 10 9 9 10 10
E 10 11 10 10 11 10 10 11

It's supposed to be 10 and 12. Is this enough to cause a noisy valve train? Is this typical that a timing belt change exposes marginal tappets?

holmesnmanny

It's likely the belt is too loose. Redo the tension procedure.

andyz

1. Does it really matter that you move the belt system over three teeth counterclockwise? If you just move it counterclockwise, making sure belts are riding right....

2. Can this tension procedure be done without removing the valve cover and the timing belt top cover?

fcm

Did you do a valve lash adjustment after replacing timing belt? 94

andyz

No, I posted the current clearances, none are too loose, which is what would make noise right? Slightly too tight during age is normal and doesn't make noise, but will eventually burn a valve, right? What could be causing the noise?

andyz

Still the same problem 2000 accord LX, stock, 110000 miles

Valve chatter at 1600 - 1900 RPM. Doesn't seem to be load related, happens even when on level ground and trying to keep at speed with light gas and getting in 1600-1900 RPM range. A little more gas, and hit 2000 RPM, the power is good and the noise is gone. No noise at idle. The power is good generally.

I did a basic tune up, wires, plugs, cap, rotor, clean TB, air filter.
I adjusted a couple of valves but none were really out.

I re-adjusted the tensioner according to the service manual, but it didn't seem to change the tension. Is there some specification that could be used like belt deflection on the accessory belts? Shouldn't a toothed belt like that be under slightly less tension than a grooved belt?

Could something have gone wrong during timing belt change? Wrong tensioner spring? Something messed up with the balancer belt that is affecting the timing belt?
TIA

andyz

Noise is gone or much reduced when cold.

Is this simple pre-ignition pinging? Why would a timing belt change suddently expose that? Is my knock sensor disconnected? Should I switch to higher octane gas on the 4-cyl '00 accord? It can't really require premium for that compression ratio could it? Is there something that can happen with the VTEC wire or solenoid that would cause noise at 1600 - 1900 RPM?

holmesnmanny

The reason for valve gap is because when the head heats up the metal expands. The gap allows for expansion so the valves close properly when the engine is warmed up. This is why you always do the valve adjustment when the head is completely cold. This is also why valves are noisy on startup and quiet when the car has warmed up. It's possible because the valves are too tight you don't hear noise when cold but when the engine warms up the valves are too tight causing noise. You won't know until you do the adjustment. That could be your issue.

andyz

Yeah I get all that. I check and adjust when totally cold and the gaps are pretty good, perhaps one one hundredth of an inch too tight so .009 when it is specced at .009 - .011 and ideally should be .010 ;; or .011 when it is specced at .011 - .013 and ideally should be .012.

I mean I am not the master expert on the feeler gauges, but I am fitting that .010 in there and I am fitting that .012 in there and it is dragging, but it FITS. I mean there is no way I can fit the .014 in there and no way I can fit the .013 in the other one, you know.

If it were really that tight, I would know it you know? I just wouldn't be able to get the .010 in there.




This noise really started when the timing belt was changed, is that typical that a new timing belt would expose ever so slightly tight valves? I can't quite understand that. It must be the belt tension, but there is no spec to follow for that, just to loosen the adjuster, which I have a feeling is jammed? or wrong spring? or the balancer belt is messing with it somehow -- and go three teeth over on cam sprocket, but I did that, and it didn't fix it.

MAD_MIKE

Did you just replace the belts or did you replace the tensioners and WP?

holmesnmanny

There is a specific procedure and you must have done it wrong. You turn the crank bolt til the engine is at tdc. Then you loosen and immediately tighten the tensioner bolt. Then you turn the crank bolt so the CAMSHAFT moves 3 teeth. Then you loosen the tensioner again and immediately tighten it again. Then you're done. The springs will have pulled the belts to the proper tension automatically.

andyz

I had a gas station shop do it. They seem pretty busy and well equipped so they ought to know how to do that model properly. The kit is supposed to include Timing Belt, Balancer Belt, Water Pump, and Tensioner.

andyz

Yeah, I got that, and can only assume the shop did that right in the first place. I have some reservations about that whole procedure because it just seems subject to variance, why do you loosen to 2/3 turn? so you don't LOOSE tension? Weird, shouldn't the spring be pulling it tight however many 2 or 10 turns you pull that acorn nut out?

Anyway, check the result and let me know what you think, please - sir.

https://honda-tech.com/forums/honda-...video-3289513/