On my 92, one tooth messes up about 14 degrees. Since my 91 is far away, I
couldn't confirm the marks on the crank pulley.

It's ok to loosen the tensioning bolt to slip the timing belt back on. You
just have to rotate the crank shaft to put tension on the timing belt
before you tighten the tensioning bolt.

Terry wrote:

> The Civic is located about 20 miles from where I live, so I am
> depending on a 17 year old girl to do some pre-testing before I arrive
> Monday. I took the valve cover off Saterday to see if the belt was
> broken or worn. We used a 3/8" 14"
> long dwoel to find #1 TDC. I wanted to check each cyl to see if the
> valve behaved correctly. I didn't even think of using the timing marks
> on the cam
> and crank pullies to check timing. I forwarded the above text to her
> and she
> made some tests.
>
> She says that the camshaft pully does not have "top" like those shown
> in her Chilton or Haynes manual, and the TDC mark is not exaclty like
> the one shown either. But that the 3 marks on the flywheel pully are
> maybe 5 degrees beyond the timing mark when #1 is TDC. There is a
> white dot, like the 1984~1987 flywheels, shown in the Chilton manual,
> that almost aligns "perfectly"
> with the timing mark.
>
> I checked my flywheel and if there is a white dot I can't find it. I
> have the 3 marks about 1/4" apart and my flywheel pully looks clean.
>
> I will look again monday morning before we go over for a barbecue.
> I have the same Chilton manual and sure enough the pictorial for the
> 84/87 shows the three marks, followed by a whte TDC mark. I wish it
> had not started raining! One web site pointed out that the timing
> marks are about 18 degrees before mechanical TDC, and they represent
> the firing starting point
> for ignition, which is advanced.
>
> The belt is less then a year old, was installed by a local machanic
> who
> has a very good rep (he is in Iraq or we would bother him), and all
> the
> parts (T-belt, water pump, tensioner and spring are OEM Honda ordered
> from Majestic.
>
> Off the top of your head any idea how far would each tooth be in
> degrees?
> What are the chances of a "good" timing belt jumping a notch?
> I was testing her water damged ECU and the engine attempted to start
> and
> the hicuped or burped, what are the chances that a faulty ECU cause
> a backfire or other event that would cause an otherwise good belt
> to jump timing?
>
> I have detailed directions (from the web) showing how to change a
> CRX belt, and the civic is very similar. I am hoping that when
> the machanic reinstalled the crank bolt that he used less then
> 1 gigaton/inch of torque! She watched the orignal belt replacement
> and says that she "thinks I can do it".[The "I" being her.] With
> the engine out of the car, I am fairly certain that I could change
> it. But doing it inplace looks a bit chancy and tight. The
> directions I have say to put a jack(topped by a wooden block)
> under the engine, lossen and remove the crankside engine mount
> and lower the engine to gain access. Assuming the crankshaft
> bolt will come loose it appears fairly straightforward.
>
> She is machanically inclined, wants to be a mechanical engineer and
> has routinly taken apart everything from the kitchen blender to a
> Briggs and Stratton lawn mower with good outcomes.
>
> Would it be stupid to back off the tensioner and slip the belt
> back into correct timing?
>
> Sorry this is so disjointed, but I am writting this in a hurry
> before friends come over for supper.
>
> Terry