Is timing belt vibration normal?
Corey872
I just replaced the water pump and timing belt on my 87 CRX DX. I
started the car up with the upper inspection cover off to make sure
everything was running smoothly and was surprised to see the timing
belt vibrating like a plucked guitar string on the runs between the
pulleys. I would estimate an amplitude of 3/4 inch at the center of
the run.
This is happening on the run from the camshaft to the main pulley
(belt in tension) and on the run from the water pump to the camshaft
(belt slack). I can't see any lower into the cover than that. I
adjusted the tension per the manual, but unfortunately did not observe
the old belt to see if it had vibration too.
Does anyone know if the vibration is normal? And if not what can cause
it?
Thanks
Corey
Mista Bone
--
Charles Tague
93 Honda Civic DX HB
1.6L SOHC VTEC 15.02 @ 89 mph,1.997 60 ft.
With ZEX 75 hp ZEX 13.54 @ 99 mph, 1.908 60ft.
86 Pontiac Trans Am
305 peanut cammed 15.62 86 mph
http://home.cinci.rr.com/mistab0ne/
"Corey872" <imapep...@excite.com> wrote in message
news:20545668.02010...@posting.google.com...
George Macdonald
Some vibration is normal. Did you check the tensioner mechanism when the
belt was off to make sure it is sliding OK?
Rgds, George Macdonald
"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??
honda master tech
sure you follow the procedure in the manual for timing belt tensioning.
it's very important. i tend to go on the tighter side of the spec.
scott
Corey872
mostly highway miles on the car...no ill effects. The belt tensioner
seemed to slide freely when I checked it.
The procedure says to loosen the tensioner pulley, turn the engine
counter clockwise 1/4 turn and tighten the tensioner. I gave it just
a little extra wiggle to make sure it was seated on the belt.
I'll give it another couple hundred miles to break in then re-tension.
Also, does anyone know of a recommended service interval for the
bearings on the tensioner pulley? ...probably should have done that
while I had everything out, since I love this car and plan to drive it
'till it turns to dirt. Of course dropping in an Si engine or VTEC
would be pretty cool, too...just not this winter!
Corey
honda master tech <car...@mail.com> wrote in message news:<3C3CE17D...@mail.com>...
Corey872
the engine is cold, and it is definitely much smoother once the engine
warms up. Everything appears normal. Looking forward to the next
100K miles!
Thanks for all the replies
Corey
imapep...@excite.com (Corey872) wrote in message news:<20545668.02011...@posting.google.com>...
TeGGeR®
pecked out:
>Also, does anyone know of a recommended service interval for the
>bearings on the tensioner pulley?
There isn't one as far as I know. Mine was fine on the first belt
change, but by the second it was loose and rumbly, so I changed it.
Next belt change is at 245,000mi for me (at 181,800 now). I'll
probably leave the current one in place.
One thing I've considered is simply replacing the pulley bearing
rather than the whole pulley. It's got to be a stock bearing number.
I'll bet Mista Bone knows that one off the top of his head!
--TeGGeR
George Macdonald
>Thanks to all the replies. Since I wrote that, I have put about 100
>mostly highway miles on the car...no ill effects. The belt tensioner
>seemed to slide freely when I checked it.
>
>The procedure says to loosen the tensioner pulley, turn the engine
>counter clockwise 1/4 turn and tighten the tensioner. I gave it just
>a little extra wiggle to make sure it was seated on the belt.
Hmmm, 1/4 turn of the crankshaft? Where did you get that procedure? The
Honda service manuals I have say to turn 3 teeth of the camshaft pulley
past TDC and I'm thinking a 1/4 crankshaft turn may be too much and have
taken you past the point of having tension on the belt. The idea is to
create tension on the belt and hold that tension while you tighten the hold
down bolt of the tensioner.
Rgds, George Macdonald
Spam Sucks
>On 10 Jan 2002 06:35:15 -0800, imapep...@excite.com (Corey872) wrote:
>
>>Thanks to all the replies. Since I wrote that, I have put about 100
>>mostly highway miles on the car...no ill effects. The belt tensioner
>>seemed to slide freely when I checked it.
>>
>>The procedure says to loosen the tensioner pulley, turn the engine
>>counter clockwise 1/4 turn and tighten the tensioner. I gave it just
>>a little extra wiggle to make sure it was seated on the belt.
>
>Hmmm, 1/4 turn of the crankshaft? Where did you get that procedure? The
>Honda service manuals I have say to turn 3 teeth of the camshaft pulley
>past TDC and I'm thinking a 1/4 crankshaft turn may be too much and have
>taken you past the point of having tension on the belt. The idea is to
>create tension on the belt and hold that tension while you tighten the hold
>down bolt of the tensioner.
George, maybe he means a 1/4 inch which would probably be three teeth.
--
nos...@zero.com
VW 94 Jetta 2.0L (A3), 89 GTI 16V (A2)
H 81 CB-750C, 86 Civic 1.5Lcarb DX HB (GFs)
Replace nospam with jetta to reply via e-mail
Corey872
The 1/4 turn came from my Chilton Manual "Civic/CRX/del Sol 1984-95
Repair Manual (8256) 30200. It was spec'ed under "Timing Belt and
Tensioner Removal & Installation" page 3-107, Item #7,:
"After installing the belt, adjust the belt tension by first rotating
the crankshaft counterclockwise 1/4 turn. Then, retighten the
adjusting bolt [in the belt tensioner pulley]."
I hope my book didn't print some bogus info (and I passed it along).
I thought the idea was just to get all of the slack on the side with
the tensioner pulley. If I would have turned it four turns or 1/4, it
would seem that the result was pretty much the same, right?
Let me know what you think.
Corey
"nos...@zero.com (Spam Sucks) wrote in message news:<3c405...@nntp2.nac.net>...
George Macdonald
>George, et al.
>
>The 1/4 turn came from my Chilton Manual "Civic/CRX/del Sol 1984-95
>Repair Manual (8256) 30200. It was spec'ed under "Timing Belt and
>Tensioner Removal & Installation" page 3-107, Item #7,:
The trouble with Chilton manuals has always been that they contain too much
generic information - one size fits all stuff. I once bought a Chilton
manual for a VW air-cooled model which had a section on draining a radiator
and refilling with antifreeze.
>"After installing the belt, adjust the belt tension by first rotating
>the crankshaft counterclockwise 1/4 turn. Then, retighten the
>adjusting bolt [in the belt tensioner pulley]."
>
>I hope my book didn't print some bogus info (and I passed it along).
>I thought the idea was just to get all of the slack on the side with
>the tensioner pulley. If I would have turned it four turns or 1/4, it
>would seem that the result was pretty much the same, right?
>
>Let me know what you think.
Well I'm trying to remember how things felt the last time I did a valve
check and IIRC, as I turn the crankshaft anticlockwise past TDC there's a
strong resistance for a just a bit and then it goes very easily and doesn't
need much force at all. Only you know if you still felt sufficient
resistance to create tension on the camshaft to crankshaft run of the belt
and, as you say, put all the slack on the tensioner side. Anyway the Honda
manuals all specify 3 camshaft teeth.
>"nos...@zero.com (Spam Sucks) wrote in message news:<3c405...@nntp2.nac.net>...
>> George Macdonald <fammacd=!SPAM^noth...@garden.net> wrote:
>> >>The procedure says to loosen the tensioner pulley, turn the engine
>> >>counter clockwise 1/4 turn and tighten the tensioner. I gave it just
>> >>a little extra wiggle to make sure it was seated on the belt.
>> >
>> >Hmmm, 1/4 turn of the crankshaft? Where did you get that procedure? The
>> >Honda service manuals I have say to turn 3 teeth of the camshaft pulley
>> >past TDC and I'm thinking a 1/4 crankshaft turn may be too much and have
>> >taken you past the point of having tension on the belt. The idea is to
>> >create tension on the belt and hold that tension while you tighten the hold
>> >down bolt of the tensioner.
>>
>> George, maybe he means a 1/4 inch which would probably be three teeth.
Rgds, George Macdonald
Corey872
<snip>
>
> The trouble with Chilton manuals has always been that they contain too much
> generic information - one size fits all stuff. I once bought a Chilton
> manual for a VW air-cooled model which had a section on draining a radiator
> and refilling with antifreeze.
>
True...this one covers three models over one decade!
<snip>
> >I hope my book didn't print some bogus info (and I passed it along).
> >I thought the idea was just to get all of the slack on the side with
> >the tensioner pulley. If I would have turned it four turns or 1/4, it
> >would seem that the result was pretty much the same, right?
> >
> >Let me know what you think.
>
> Well I'm trying to remember how things felt the last time I did a valve
> check and IIRC, as I turn the crankshaft anticlockwise past TDC there's a
> strong resistance for a just a bit and then it goes very easily and doesn't
> need much force at all. Only you know if you still felt sufficient
> resistance to create tension on the camshaft to crankshaft run of the belt
> and, as you say, put all the slack on the tensioner side. Anyway the Honda
> manuals all specify 3 camshaft teeth.
>
I see your point. If you are at TDC on one cylinder, you are probably
coming up on compression on another, giving the overall assembly some
resistance. Then, you may hit a point where all cylinders are in
transition and no real resistance on the crank. I think I would trust
Honda over Chilton! Next time, three teeth it is!
Thanks for the info,
Corey