Timing Belt Tension Problems

it comes from the service manual.

but that only tensions that one length of belt. you need to rotate to
ensure all the lengths between all the rollers have adequate tension.

 

operation is very straight forward - need to rotate the engine to
ensure the belt is sufficiently seated on all pulleys and that tension
on all the runs is in equilibrium. then, the tensioner can take up on
the "slackest" run of the belt. the spring is perfect for this.

 

operation is very straight forward - need to rotate the engine to
ensure the belt is sufficiently seated on all pulleys and that tension
on all the runs is in equilibrium. then, the tensioner can take up on
the "slackest" run of the belt. the spring is perfect for this.

 

$:

Take some pics. Post them.

They don't change much over the years. Our '99 Tercel's works the same way
as my '91 Integra's.

 

$:

Take some pics. Post them.

They don't change much over the years. Our '99 Tercel's works the same way
as my '91 Integra's.

 

except your Tercel is non-interference design...

Also, is there really a huge danger to damage the valves if you are only hand
turning the engine? I have seen several instances on the group where valves
did not get damaged when the engine was at low speeds. I guess your theory
is 'why take a chance?', and it does make some sense.

t

 

Not that this would help you now, but the way we ensured proper belt, cam,
and crank position on my bro-in-laws 01 Accord was to mark the belt and
pulley with white-out on the pulley marks.

Once the belt was off, we counted the number of teeth from each mark on the
belt, then put matching white-out marks on the new belt. We then slid the
new belt right on to the engine, and everything lined up perfectly!

I will be using this method on every timing belt I do from now on. It
totally took the 'fear factor' out of being out by a tooth or 2.

Any thoughts on the above?

t

 

This is indeed exactly what Idid. But then I set the
tensioner incorrectly. I drove around 20 miles with
symptoms, not knowing what exactly was wrong. The next
day,tTroubleshooting the tensioner resulted, at one point,
in a too slack TB. The TB slipped, and the car would not
start. The camshaft and crankshaft had both been rotated
quite a lot by this time, so the marks became meaningless.

I have used it in the past and it is the way to go.

I am still stunned at how lucky I got yesterday. I moved
both crankshaft and camshaft independently of each other a
lot, too, prior to re-installing the belt. Late yesterday
afternoon I was really beat and sort of slapped the belt
back on, thinking no matter how careful I was, I'd have to
re-assemble nearly all, try to start it, check the timing
with my timing light, estimate how far off I was, then
disassemble all and adjust by a tooth or more.

After around 30 miles of driving today, my Civic is still
running great. I will feel better after a full week has gone
by, though. Still, I celebrated with the purchase of four
new tires and an alignment (by an import specialized shop
which explained everything they found) this morning. The
ride is really smooth. I am stylin' in this old but
incredibly reliable and fuel efficient car.

 

So, there was a happy ending to this saga. You are braver than I -- I don't
touch them anymore. It was easy in the old days when I had a Sunbeam Tiger
or was tuning a 1970 Honda CB 750 or an an older Triumph Bonneville.

 

Theoretically, yes. But the clearance is on the order of a few
thousandths of an inch. A bit of carbon buildup and suddenly it's an
interference engine.

Absolutely. At all times there will be a few valves that are open. If
the belt is off and one valve is sticking way down and you crank the
engine just a bit too vigorously, that valve goes V-shaped. Serious
interference.

Even at high speeds. My boss's CR-V's belt snapped on him on the
freeway. No valve damage. (He was at almost double the recommended
replacement mileage, so it's his fault.)

That's because both cams and cranks are moving of their own inertia.
They will tend to stay more closely in time than the example above, and
will tend to stop more-or-less together as well.

I also suspect some Honda engines are just barely interference designs,
sort of like the Tercel's engine. Or maybe Honda is being conservative
in its labeling practices.

 

Just exactly what I do. It helps immensely in preventing the "one tooth
off" error.

Excellent idea.

 

See http://home.earthlink.net/~honda.lioness/id21.html for
photos, along with an explanation of where I am confused. I
started a discussion at honda-tech.com as well. So far, one
person has commented that the "hole" has to go on a certain
peg. Which makes some sense, since I was wondering what the
hole opposite the one where the tensioner attaches is for.
Newer Civic tensioner adjusting instructions make reference
to pegging down the tensioner..., though the design is a bit
different.

I think I may have to go back in there and at least check
everything. All is fine after a few days of driving around
100 miles, highway and suburban. But...

 

See http://home.earthlink.net/~honda.lioness/id21.html for
photos, along with an explanation of where I am confused. I
started a discussion at honda-tech.com as well. So far, one
person has commented that the "hole" has to go on a certain
peg. Which makes some sense, since I was wondering what the
hole opposite the one where the tensioner attaches is for.
Newer Civic tensioner adjusting instructions make reference
to pegging down the tensioner..., though the design is a bit
different.

I think I may have to go back in there and at least check
everything. All is fine after a few days of driving around
100 miles, highway and suburban. But...

 

I had a look at the photos on your site.

Something does not look right.

See how the tensioner has a kidney-shaped hole in it? You'll notice the
curve of the hole is axial to the pivot hole shown to the right of the
photos.

The spring is shown extending radially from the tensioner. This is surely
incorrect: the spring cannot operate in this orientation. The spring should
be rotated 90 degrees either one way or the other from its current
position. In other words, it should be TANGENT to the tensioner.

The purpose of the spring is to pull the tensioner away from the
crankshaft, pulling the belt with it. The spring must be AXIAL to the
crank, but TANGENT to the tensioner.

See this pic:
http://www.tegger.com/hondafaq/misc/tensioner.pdf

I marked it up kinda quickly, so you may have to spend a bit of time
figuring out what goes where.

If this is not clear (and I suspect it will not be), let me know and I will
redo in more dramatic fashion.

 

I had a look at the photos on your site.

Something does not look right.

See how the tensioner has a kidney-shaped hole in it? You'll notice the
curve of the hole is axial to the pivot hole shown to the right of the
photos.

The spring is shown extending radially from the tensioner. This is surely
incorrect: the spring cannot operate in this orientation. The spring should
be rotated 90 degrees either one way or the other from its current
position. In other words, it should be TANGENT to the tensioner.

The purpose of the spring is to pull the tensioner away from the
crankshaft, pulling the belt with it. The spring must be AXIAL to the
crank, but TANGENT to the tensioner.

See this pic:
http://www.tegger.com/hondafaq/misc/tensioner.pdf

I marked it up kinda quickly, so you may have to spend a bit of time
figuring out what goes where.

If this is not clear (and I suspect it will not be), let me know and I will
redo in more dramatic fashion.

 

RADIAL, sorry.

 

RADIAL, sorry.

 

that spring doesn't look right. it's /definitely/ not correctly
oriented. it should be a shorter thicker spring, and it's got a plastic
sleeve on it. it hooks onto a pin above the idler so that it causes the
idler to rotate about its fixed pivot point.

 

that spring doesn't look right. it's /definitely/ not correctly
oriented. it should be a shorter thicker spring, and it's got a plastic
sleeve on it. it hooks onto a pin above the idler so that it causes the
idler to rotate about its fixed pivot point.

 

RADIAL, sorry.