Timing belts

I have 2 Honda Accords, a 2001 V6 and a 2002 4 cyl. If the timing belt
breaks, will it cause extensive engine damage?

The manual on the V6 is unclear when to change the belt it says to change it
at 60,000 miles if you drive in very hot or cold conditions. I do not have a
manual for the 4 cyl, it was a used car. It has 94,000 on it now and runs
perfectly.

 

I believe the recommended change period is 105K miles or 7 years under
normal conditions. My own interpretation of very hot has always been
desert type conditions (Death Valley, Sahara), very cold would be
similar to the northern Midwest areas and Canada/Alaska for the 60k
change.

The key is not just the belt itself, but the internal cords/fibers
that do not allow the belt to stretch, which are usually made from
Kevlar/Twaron (both are aramid type high tensile fibers). I'm not
sure if the base OEM Honda belts are rubber, HSN or carbon fiber type
(I would suspect that they may be the one of the latter two, as at
some point in the 90's they increased the recommended belt change
interval by a fairly large amount).

Here are a couple of articles you may want to read....especially the
thermal properties of the Kevlar and interference engines.

http://en.wikipedia.org/wiki/Timing_belt
http://en.wikipedia.org/wiki/Kevlar

The potential damage from a broken belt is quite extensive, and you
may or may not see any symptoms.

 

irc, kevlar is subject to accelerated fatigue when subject to humidity, so
i believe the cords in high quality timing belts are usually glass fiber.
the above link does allude to glass fiber use, although not in detail.

with an interference engine

....prior to breakage.

 

"Glass fiber" is a misnomer, as it still uses a polymer carrier (ie,
flass filled kevlar) as far as I last was aware of.

Polymer with 30%-33% glass fiber by weight is usually what you will
find in most industries. The higher percentages the more prone it
will be to fracture at a specific radius due to extremely high flex
modulus.

 

http://www.gates.com/part_locator/index.cfm?location_id=3598&go=Interference

Most belt driven Hondas run interfering valves that will be extremely
unhappy if the piston/valve timing fails.

Unless you can determine with some certainty that the belt has been
changed, you should start thinking about getting it done. As mentioned,
~100K is the highest likely service interval. As the belt ages, it will
become statistically more likely to break. If it's a 100K belt, you'd
be 'fairly' safe for another 10~20K, (and it's not 100% guaranteed to
break at 150K.) But each passing mile increases the odds (at an
increasing rate!) of a VERY expensive boo-boo.

A belt inspection might be possible with little effort/cost. Find what
belt Honda uses for OEM, and how they are labled. If you find something
different (aftermarket), you'll know that someone changed it, presumably
sometime near the service interval. If you find a Honda belt, there
might (???) be a date code or batch number indicating it's age.

 

You 2002 4 cylinder may not be a belt, it "may" be a timing chain, in
which case, no worries. Look at the thread just below this one about
an 03 4 cylinder, in the 03s, the 6 cylinder is a set of belts, BUT
the 4 cylinder is a timing chain. I'm not sure what year this started
for the 4, but maybe you get lucky on that one.

 

Both are timing belts, not chains, as a quick check of
bkhondaparts.com shows. For both of these, in the owner's
manual under "maintenance schedule," it says to change the
belt at 105k miles/7 years, whichever comes first.

So the 2001 is overdue in my book. The 2002 is almost due.

These are both interference engines and so there is a high
risk of engine damage if the timing belt fails in any way.

It is clear in the "maintenance schedule" section of the
manual.

You can see an owner's manual for any Honda car via site
https://techinfo.honda.com/rjanisis/logon.asp

 

2003 was the first year that the Accord's 4-banger was chain-driven. So
this 2002 in question has a belt.

 

Thanks to everyone that provided information and links.

It really sucks that I'll have to spend $800-$1000 on my 2001 Honda V6. The
car only has 24000 miles on it but is 7 years old. That almost makes me want
to trade it in for a new car, one that doesn't use a belt that cost mega
bucks to change.

 

Hi,
You have to see that belt change is time consuming and also it is good
time to to the water pump while at it. Belt itself does not cost much.
Some cars have timing chain.

 

If Honda is going to use a part that must be changed as part of the routine
eminence schedule, it should be designed so it is easy to change. I consider
it poor design.

 

How would you improve on this design?

Have you run the numbers to see whether it pays more to
replace the TB and keep the car vs. buying a new one?

Once every 7 years/105k miles is not routine. The typical
Honda owner probably changes the TB exactly once while
owning the car, after all.

 

Hmmm,
Designing something involves many factors. It is not as simple as you
might think. What is your definition of poor design? If you don't like
to spend some $$ at 100K miles or so, is it poor design? I think not.

 

I would say it is more likely that most Honda owners do not keep their car
for 7 years. They unload them before this expensive, necessary belt change
is due.

 

Many people trade in their Hondas (among other car makes)
for a new car when the timing belt is due because they
cannot do simple financial calculations. Keeping a car for
14 years/210k miles and spending $1000 once for a timing
belt in that period is an excellent financial choice
compared to buying a new car every 7 years/105k miles. As
importantly, do you know of a car make that is clearly more
reliable, and so is less costly to maintain, that costs less
to purchase than a Honda?

 

I don't think so - poor design would be the 2.6L Mitsubishi "silent shaft"
engine that was in our 1984 Dodge 600. The timing chain needed replacement
at 94K miles (it was rubbing the housing). The first step was to remove the
engine to allow the timing chain cover to be removed. I am told there have
been great improvements in chain design since then, which allow chains to
last the life of the engine. The timing chains I remember from my youth had
life expectancies of 60K miles.

I've replaced a couple of Honda timing belts (as well as a Volvo and a
Nissan belt, and a Ford belt - on the side of the road! - back in the '70s).
They aren't really any worse than average, in spite of the rumors that the
belts - timing and balance - in my daughter's '93 Accord were exceptionally
tough. The parts costs add up, though, with a tensioner for each belt that
really should be replaced at the same time. It is also foolishness to not
change the water pump while it is exposed. $240 and eight leisurely hours (I
work very slowly) did the trick for another half decade for the Accord.

Now, changing the clutch in my son's Acura... there was a struggle!

Mike

 

Oddly, this is not completely accurate. My '85 Volvo had a provably
non-interference engine (a Volvo guru even ran all the clearances with every
available cam) but the list showed it to be interference. Hmm.

I love understatement!

Exactly so. Consider the logic of the situation: if you don't know when the
belt is due and elect not to change it now, when will it be done? My guess
is: too late. Once you change the belt you will know when the next one is
due. And I can almost guarantee if the belt has been changed the seller will
be showing you the receipt, because it adds value to the car.

Mike

 

That's a very good statement of the situation, although I would add that
many people are thinking about trading in their 7 year old car anyway and
are prompted by the looming cost. In any event, I think Hondas in that
category can be very good values. They have enough miles that the evidence
of how they have been treated is hard to hide, and they have a high
likelihood of providing reliable transportation for at least another decade
with low service costs. Doing your own maintenance is definitely a plus in
keeping the costs down, but in any event the 2002 is very likely to be more
economical overall than a brand new car. My son-in-law is looking for a car
and I would certainly recommend a car like that. What the OP said about the
seller's honesty is a much bigger problem.

Mike

 

I like to keep my car maintained, I change the oil regularly and do other
recommended maintenance.

This expensive timing belt thing is changing my way of thinking. It would be
cost effective to keep a car for 4 years, only change the oil once or twice
then trade it for a new one. The money saved on all that increasingly
expensive maintenance would be almost pay for the new car, and I'd have a
new car every 4 years. I'm sure there are a lot of people that do that.

 

Hmmm,
The more new cars you buy, the more money you lose. Cost of money,
insurance, etc. My runaboubt '98 CRV has ~260K Km now and so far it
needed a brake job, two sets of tires, timing belt/water pump
replacement and I paid cash when I bought it. Other minor maintenance I
do it myself. So far it does not burn oil, it does not sqeak or rattle,
everything works like new. Being retired all I need is a reliable car. I
am going to keep this car until econmically it is not
wise idea to keep it any more. Then I'll go out and get a new car with
cash again, probably another Honda. My family has 4 vehicles of varying
ages. All Japanese brand.