Re: Tightning the belt, its all in the timming.

[jdouglas@mitre.org (jason douglas)]

I worried about belt replacement for some time.  Because of the tools, I
elected to watch a pro do the job.
>
>1) First, I want to make sure there isn't a bent valve. Is is sufficient to
>rotate the cam 360 deg.? I really don't want to pull the head. 

The 8v and 10v normally aspirated engines are non-interfering.

>2) Since the water pump has to be disturbed in order to adjust the new belt,
>Is it prone to leaking afterward. i.e., Should I just play it safe and buy a
>new H2O pump?

This is a philosophical question.  How old is the old pump?  I had the pump
replaced on my car.  At 95,000 miles it seemed that there wouldn't be too
many miles left in the pump, and sure enough, it did have a small leak.  A
new pump will only set you back $50-60 and there is no extra labor involved
to replace it.  Replace it later and it will cost you several hours of
labor.  Since the pump is used on the 5 to tension the belt, you will
probably have to move the pump (and destroy the gasket) anyway.  Just
replace the whole thing.

>3) Bentley suggests using a couple of special tools.  One to lock the crank
>against the engine mount, and the other is a "breaker bar" with which they
>give torque specs.  Do I really need them?  Can I lock the engine in gear
>with someone standing on the brakes? Would a pry bar in the ring gear work?

Probably.  It is a lot of torque - about 200 ft pounds, nearly twice as much
as the engine develops.  There might be chance of breaking a tooth on the
flywheel.  Am I out to lunch, net gods?.

>How about the breaker bar?  Can I just use a really big torque wrench when
>tightening?

Sure

>4) My cam seal has been leaking oil for some time.  Not enough to worry
>about, but now is the time to replace it.  Again, Bentley shows a special
>tool, - any tips? What if I replace the cam (Schrick 268) do I need the tool?

Aha - have heard that belts generally fail only if they get oil on them.  It
degrades the rubber.  Did said oil actually get on the belt?

With that said, you may want to replace the valve cover gasket if it is leaking.

>Whether or not I put the Schrick in is dependent on price but if I do, I
>will post a review complete with before and after numbers through the RPM
>range.  I'm not going overboard with a cam as I'm at 5300' and only have an
>8.5:1 CR.  

I'll be waiting to hear the results :-)

>I Checked the archeives for info on timing belt replacement. None found.
>Would this make a good FAQ topic? 

I second the motion!

>Just out of curiosity, why do you have to remove the lower sprocket, etc.
>from the crank? 

If this is a 5 cylinder, stick your head under the front of the car and look
at the pulley.  There is a casting on the front of the engine that covers
the bottom of the pulley.  The space between the front of the casting and
the edge of the pulley is too narrow for a belt.  Without taking the pulley
off, the only way to get a belt on or off will be to cut it (ouch).
>
Jason Douglas
86 5000S