1993 Corolla LE valve timing

1993 Corolla LE, 1.8 L, 7A-FE engine, 300,000 km (186,000 mi).

Jack confesses,

What have I done to this poor car? I did something I shouldn't have when I
was changing the timing belt. Usually I put soft rope in #1 cylinder to
hold the crank so that I can undo the harmonic balancer bolt.

I don't know what got into me but... this time I 'experimented' by putting a
rag between the camshaft gears. I gave up on this right away, after a
tentative pull on the crank pulley bolt with the 20" Johnson bar. The gears
didn't move much, and it was obvious right away that the old belt was too
springy to hold enough to loosen the crank bolt.

Although I checked the cam timing marks carefully on installing the new
belt, the distributor timing was way off, as a timing light showed. (When
setting the distributor timing, I jumped the specified terminals to
eliminate computer moderation.)

Now I am getting around 31.5 m.p.g. instead of 40.4 m.p.g. on average. When
fully accelerated suddenly, the car seems to hesitate for a split second.
Otherwise, the car appears to run normally overall, with perhaps a bit less
power.

Is the valve timing off? Have I twisted the timing belt gear on the end of
the camshaft? How would I go about diagnosing the damage?

Your expert comments would be much appreciated,
A very repentant
- Jack

"Ralph" <nospam@thanks.com> wrote in message
news:454aa4ba_1@news.cybersurf.net...[color=blue]
> 1993 Corolla LE, 1.8 L, 7A-FE engine, 300,000 km (186,000 mi).
>
> Jack confesses,
>
> What have I done to this poor car? I did something I shouldn't have when
> I was changing the timing belt. Usually I put soft rope in #1 cylinder to
> hold the crank so that I can undo the harmonic balancer bolt.
>
> I don't know what got into me but... this time I 'experimented' by putting
> a rag between the camshaft gears. I gave up on this right away, after a
> tentative pull on the crank pulley bolt with the 20" Johnson bar. The
> gears didn't move much, and it was obvious right away that the old belt
> was too springy to hold enough to loosen the crank bolt.
>[/color]

I thought I knew a lot of tricks, I'll admit that that is the first time I
heard of putting rope in the cylinder or a rag in the gears <g>

In the future, you may want to invest in a spanner-type tool to hold the
pulley while you remove and install the bolt. OTC supplies Toyota dealers,
and the tool can be used on most Toyotas, or you may be able to find a
generic tool to do the job or invest in a compressor and impact gun.
[color=blue]
> Although I checked the cam timing marks carefully on installing the new
> belt, the distributor timing was way off, as a timing light showed. (When
> setting the distributor timing, I jumped the specified terminals to
> eliminate computer moderation.)
>
> Now I am getting around 31.5 m.p.g. instead of 40.4 m.p.g. on average.
> When fully accelerated suddenly, the car seems to hesitate for a split
> second. Otherwise, the car appears to run normally overall, with perhaps a
> bit less power.
>
> Is the valve timing off? Have I twisted the timing belt gear on the end
> of the camshaft? How would I go about diagnosing the damage?
>
> Your expert comments would be much appreciated,
> A very repentant
> - Jack[/color]
I doubt if you can exert enough torque on the crankshaft bolt to twist the
timing belt gear on the end of the camshaft. If camshaft timing is off, the
engine would run pretty poorly all the time.

Check for a vacuum leak and check distributor timing advance.
--

Ray O
(correct punctuation to reply)

Thanks Ray O.

Whatever I did put the distributor off somehow, I gather, and it is driven
(I think) by that camshaft which is in line with the belt gear (as opposed
to its twin shaft).

Does the fact that the distributor was pushed off mean the camshaft is off
too? (It was retarded, thus out by 10 degrees or more.)

Thanks again for your comments.

"Ralph" <nospam@thanks.com> wrote in message
news:454ae23b_2@news.cybersurf.net...[color=blue]
> Thanks Ray O.
>
> Whatever I did put the distributor off somehow, I gather, and it is driven
> (I think) by that camshaft which is in line with the belt gear (as opposed
> to its twin shaft).
>
> Does the fact that the distributor was pushed off mean the camshaft is off
> too? (It was retarded, thus out by 10 degrees or more.)
>
> Thanks again for your comments.[/color]
If distributor timing was off by 10 degrees AND the distributor hold-down
bolt was tight, I would double-check the camshaft timing. I imagine that
the engine would barely run if one of the camshafts was off by a tooth, but
it might run well enough for the symptoms you're describing.
--

Ray O
(correct punctuation to reply)