1991 timing belt question

hello,

i am doing the head gasket on my 1991 civic. if there's any advice on
this subject, feel free, but my real question is about timing.

there seems to be a paradoxical aspect to replacing the timing belt.
first of all, my crankshaft pulley has no markings. secondly, all the
instructions i've seen requires the lower timing belt cover to be
installed before you can use the indicators on it to adjust the
position of the belt. however you cannot adjust the belt with the
cover on. am i missing something?

also, is there a more reliable way to find TDC than to stick something
through the spark plug hole and watching for TDC? it seems so
inaccurate... i suppose that's what the markings are for, but i've
already pointed out the connundrum there.

thanks!

josh

 

There's supposed to be two side marks on the cam shaft pully to make
parallel with the surface of the top of the head with the word UP on
top of the gear pully.

 

Does the pulley look anything like the following?

http://www.norcalcrx.org/fig_6.jpg

Mind you, though, I think you're confusing fine-tuning the
ignition timing (which requires a timing light and using the
marks in the photo above) with properly aligning the timing
belt, crankshaft sprocket, and camshaft sprocket. Certainly
if the timing belt isn't installed so that the camshaft and
crankshaft are "in synch," you will have major problems fine
tuning the ignition timing subsequently. So both involve
timing, but they're different steps for tuning one's car.

I think you are missing something.

What do you mean by "adjust the belt"?

You want to ensure that the camshaft is "in synch" with the
crankshaft. That's accomplished by making sure that the
camshaft and crankshaft are fixed in the proper position
when you install the timing belt. That's actually very
tricky, unless you do the following: Prior to removing the
old timing belt, mark with a Sharpie marker or "White-Out"
teeth on the camshaft sprocket and their coinciding belt
teeth. Do the same at the crankshaft sprocket. When you have
the belt off, lay the new one next to it, and mark its teeth
exactly as the old belt's teeth are marked.

Are you using a manual? www.autozone.com has a free online
manual for your 91 Civic. Otherwise, see above and Alan's
comments.

 

There is a square hole on top of tranny below the #4 spark plug. You
will see a pointer. Turn your engine untill you see the letter "T",
that's TDC. Same hole you use to adjust ignition timming.

 

obviously i would have marked all this up, but i lost the factory
"setting" when i did this the first time a while ago when i was still
green. i think the belt that i had put on then was off by a tooth, so
i'm more or less starting over this time.

okay, i took a closer look at the crankshaft pulley and the marking are
there, they were just obscured and had lost their paint. there is a
series of three markings, which i think are ignition timing markings.
there is one more marking, slightly clockwise of the three, which
according to the auto zone online manual is the TDC mark. see figure 5
under the '91 engine section:

http://www.autozone.com/servlet/UiBroker?ForwardPage=/az/cds/en_us/0900823d/80/14/13/29/0900823d80141329.jsp

so, as you can see, in order to align the crankshaft pulley, you must
have both the lower timing belt cover installed and the crankshaft
pulley installed. both these items make it impossible to actually put
on the timing belt. so all i can think of is that you must install the
lower timing belt cover and the crankshaft pulley, align for TDC,
remove those two items without disturbing the crankshaft, align the
camshaft with the two lines on the sprocket on the same plane as the
head (with UP up) and slip on the belt.

is this right? i still need to look into William Burke's suggestion...

thanks for your help. this is the best honda forum i've run across yet!

 

-------------------------------------

Read this, and all the other stuff that surrounds it.

http://www.tegger.com/hondafaq/crankbolt.html

'Curly'

 

The price of Usenet posts is sometimes thinks aren't obvious
to the reader. I understand where you're at now.

Yes. Figure 5 above is exactly what's in the Service Manual
as well. Autozone has mostly Chilton's and Haynes manual
stuff, but occasionally exactly what's in the Factory
Service manual is in these manuals, too.

You just install everything loosely in order to get the
crankshaft sprocket "in synch" with the camshaft sprocket.
Then, yes, it all comes off again to get the belt on.

I agree it's going to be a little tricky to get the belt on
so the two shafts are as in synch as possible. I confess I
bet it's darn easy to be off a TB tooth. I'd mark things at
every attempt, to keep track. Being off a tooth will be
obvious.

Keep checking back to see if anyone has other ideas. I have
done a whole whopping single TB change in my life but I
researched the matter like mad and had a lot of help here. I
did the white-out thing and it worked great.

Yes, it's a good group. And we always agree on everything.
;-)

See also the Concerto and CRX service manuals at
http://www.honda.co.uk/car/owner/workshop.html . Sometimes
the service manual is superior to the pretty much Chilton's
manual at the autozone site.

 

thanks so much. i'll revive the thread if i have any more questions.

josh

 

Why create extra work for yourself? With all the timing belts I've done
over the years, I've never had to do that. Just set the crank so that
keyway notch is as close to up as you can get it, put the belt and lower
covers on, the cam should be aligned by the pulley markings, once you get
the lower cover and crank pulley on fine tune the crank's position, then
pull the belt up over the cam pulley, adjust the belt tension (there's an
access hole in the lower cover), spin the engine over by hand a couple of
revolutions and recheck the timing marks, and be done with it. There's no
need to remove the lower cover once you get the new belt on, nor have I ever
found it necessary to put marks on the belt or pulleys. I also usually
recheck the ignition timing once the car warms up. If it was OK with the
old belt, then it should be OK with new belt. A degree of difference might
be attributable to belt stretch, but it'll be much worse if you've skipped a
tooth. I usually find no change in the ignition timing if the belt was
installed correctly.

Eric