Bad Timing Belt?

Hello,

The timing belt on my '95 Civic ESi (1.6L SOHC) is about 4 years old,
and was used for less than 40K kms (25K miles). But I notice it had
deep cracks on the outer (smooth) side, at each gap between the teeth.
The cracks are mostly very straight, and so the belt looks "segmented".
They're also deep, going about halfway into the belt's thickness.

I have a feeling this isn't normal. Is it? If it's really bad, how
could it possibly have gotten this bad, when it's still relatively
fresh and was installed by the Honda dealer? I would really like to
prevent it next time.

Thanks in advance..

 

Are you sure you're referring to the timing belt? Here's an illustrated
index of the timing belt from the factory service manual.
http://media.honda.co.uk/car/owner/media/manuals/CivicManual/pdf/6-18.pdf
The reason I have to ask is that I've never seen a timing belt cracked as
badly as you describe. If it was, then it would probably break in very
short order and the car would no longer be running. Most timing belts fail
well before then become cracked as you have described and that is after
they've been in the car >90K miles though some do fail prematurely however
that's rare.

Eric

 

Sure you don't mean one of the serpentine belts for the alternator,
etc...?? Normally, the timing belt is covered and you can't see
it. I would change any belt that was that bad, timing or serpentine...
Slight cracks in a serpentine belt are ok, but if they are half way
deep,
I'd change it. That belt might run the water pump, "not sure on that
model"
and losing it is the last thing you want to do. Also, belts always fail
at the
worst possible time due to "Ruprects Law".
MK

 

if that were my timing belt, i'd drop everything else i was doing and
fix it immediately. seriously. sounds like the dealer either didn't
change the belt at all or that it was installed too tight. whatever the
reason, that is a very sick belt and cannot be trusted another inch.

 

I'm afraid that's exactly the belt I'm referring to. This model is a
"domesticated" version of the EX, with basically the same engine
(D16z6).

I wouldn't even have seen the cracks if the mechanic hadn't pointed it
out when I was having the tires rotated. When I got home, I removed the
valve cover and belt cover, and saw the cracks. So this is bad, huh? I
wonder what could have caused it... I hear these things normally last a
long time.

Thanks for the replies.

 

Here's an illustrated

.... odd that they refer to the drive / driven components as pulleys
instead of sprockets.

 

"Ruprect's Law" ??

 

How'd the mechanic see it if there's a cover over it?
What was he doing under the hood while rotating tires?

 

Hello jim. It was on a lift for the tire rotation, and we decided to
take it up a little higher to check under it. Using a flashlight, he
basically saw just the lower section of the timing belt/pulley. I was
skeptical too, at first, thinking the grooves were too regularly spaced
apart. But when I got home and took the valve cover and belt cover
off... Possibly this belt was put on *too* tight, or was of a quality
for which the word "aftermarket" is too kind.

Anyway I would love to do this myself, so I'm looking through the posts
and reading the service manual, I still can't figure out how to take
that stubborn "special bolt" off...

 

Check out the options here: http://tegger.com/hondafaq/cranktool/index.html
As TeGGeR says, an impact wrench is the overall best way. If you can rent a
hefty electric one with a socket to match you should be okay. Note that
regular sockets must not be used with an impact wrench as the brittle
regular sockets can explode. In any event, don't blow off the need for eye
protection.

It can be a challenge, but it can be done. Besides the special techniques, I
think the special bolt requires special vocabulary. But once it moves the
rest is downhill.

Mike

 

crankshaft pulley bolt torque spec for my B18 DOHC motor is 130 ft-lbs,so
you'd need a impact driver with torque greater than that.
(probably a LOT more!!)

My Haynes manual suggests a strap wrench to hold the crank pulley still
while using a 1/2" driver socket and breaker bar.

 

It sounds like the lower timing belt cover was missing;it seems to me that
the timing belt should not be exposed that one could see it.

Maybe that's why your new belt is degraded?
It was left exposed to the elements by a missing cover.

 

pah, haynes. good luck with the strap - you will indeed need "special
vocabulary" trying to do it with one of those. bolts lock in there for
/way/ more than 170ft.lbs to loosen.

***

to the op, buy the proper holder tool, then sell it on ebay if you don't
need it again. or you can rent the factory tool from some honda dealers.

belt replacement is relatively straightforward once you remove the bolt,
and get the accessories out of the way. a/c and steering pumps both
move without the need to disconnect pipes, even though it may not be
obvious at first sight.

when installing the new belt, make sure you tension correctly. google
this group on how to do it as it's been posted a number of times this year.

write back if you have questions.

 

i second that.

 

From reading here and elsewhere, and keeping an eye on my
own, 91 Civic's timing belt, I agree this does not seem
normal. Do you know who the belt manufacturer was? Who
changed it last, anyway, the dealer or an independent shop?
Maybe ask them from where they get the belts, or it might be
printed on the belt.

OTOH I do not recall reading caveats about belt
manufacturers, perhaps because there are so few
manufacturers and they generally produce high quality belts.

What sort of driving conditions does this car see? Anything
that would qualify as "extreme" per your owner's manual?
E.g. a lot of dust, cold starts, Canada-like temperature
extremes?

Has oil per chance leaked onto the belt? There are cautions
about avoiding this on the net and when changing it.

Jim Yanik's theory sounds plausible, too. On my 91 Civic, I
do not think one can see the sort of detail you're
describing by looking at the belt from the bottom. The angle
is too extreme.

On the "special" pulley bolt: If I (an amateur who has
slowly been accumulating more proficiency in the last ten
years) can get it off using hand tools, I think just about
anyone can. The route that may be most reliable and least
expensive may be taking the car to a garage, having them use
their super-duper air impact wrench to loosen the bolt, then
just snugging it up for the presumably short trip home. That
bolt typically requires serious torque to break free, but I
think that's mostly due to it being a fine thread subject to
heat cycling over a period of years, so the female and male
thread metals tend to "meld" together.

A lot of folks here report having just run the car to their
local garage and tipping the techs there $10-$15 or so for
breaking the bolt free.

Another resource:
http://home.earthlink.net/~honda.lioness/id6.html

I trust you are not driving the car at this point. Doing so
risks a broken or failed belt, potentially destroying the
engine.

 

Thanks to everyone for taking time to reply. I posted a photo, if
you're curious:

http://hondaswap.com/attachments/general-tech-maintenance/1034d1159641356-my-cracked-timing-belt-treo_093006_001.jpg

 

Thanks. No shortage here of that "special vocabulary".
Any other tricky things to watch out for?

 

Hmm.. That could be it. I thought it funny for Honda to leave it
exposed like that. Since the rainy season began, this car has waded
through ankle-deep water a few times, and sometimes it splashes into
the engine bay. Could it be that being hot and getting wet caused the
cracking? I guess some previous mechanic forgot to put it back..

 

Apart from wading into ankle-deep water a few times, it doesn't see
very extreme conditions. Weather is mild here, if somewhat hot and
humid. No evidence of oil on the belt, at least not now. It did have a
slight leak at the head gasket, before I replaced it. It's an easy jump
from there to the belt.

As cars this age go, it has relatively low mileage: less than 60K
miles.

Thanks for the advice, Elle. Since getting all your responses, I
prudently avoided running the engine. This afternoon I sprayed
penetrating oil into the bolt, to maybe help it along. What hand tools
did you use? I assume you made your own special wrench.

 

"Mechanic" is too nice of a word for someone who "forgets" to reinstall the
lower timing belt cover.

Eric