Greg,
I took pictures of the U20 from my parts car when I before I changed the upper
chain so I would have a record. I sent these pictures, and a couple of pictures
from the Clymer manual to Allen in the hope it would help him. The well lit
Clymer picture, and my much poorer lit picture, pretty much match when you look
at the cam gear position. I had to assemble and check things two or three times
before I was sure I had everybody in the position I wanted them in. I was off a
tooth or two the first time.
The chain reference links DO move around the circumference of the chain when you
rotate the engine. The biggest problem I had was counting the links between the
cam gear and jack shaft gear. Everything I can find calls for 38 links between
these two gears on the right side (left car) as you look at the chain. No
matter
how many times I counted it I think I came up with either 18 or 19 links. I am
still confused about that one unless they count the double row as two links.
If he is off a tooth I am pretty sure he would have touched a valve to a piston.
Whether it is enough to bend the valve I don't know. I bought a 68 2000 new and
retimed it to some 12 degrees BTDC for the extra power. From this list I have
recently learned how hard this is on the chains when you have a smog dizzy. In
about 15,000 miles I jumped a tooth on the chain. If I remember correctly I
replaced at least two valves on a head that was uncut.
As to list troubles. Make sure you delete the Major Domo trailer at the end of
each message you reply to. I am still learning that one as well.
Tom
69 2000
Portland
Vicki Burrows wrote:
> I seem to be having trouble getting info and questions to the list in
> my/our effort to figure out this car. I had a question to follow up on
> allen's about checking mechanical timing. I wonder if the cam is one
> tooth off. The only way I know to check it would involve pulling the
> front cover and counting links. However, I was wondering if anyone out
> there has a 2 liter on a stand or out of the car who can do the
> following: Put the chains on properly, put the front cover on and put
> the engine at TDC and tell us the exact location of the cam dowel pin.
> I want to know if the timing pointer on the front cover is a reliable
> mark that we can use to see if the cam is one tooth off. Also,
> according to the manual, when you set up the chains the timing mark on
> the cam gear is supposed to be in the middle of a link, and not
> between... does that change when the engine is rotated several times (I
> would not think so, being that the timing of the engine should remain
> the same, but ?). Also, if the cam is one tooth off, would the engine
> run? Any idea how many degrees of retard or advance one tooth would
> be? I know that there are adjustable cam sprockets, but I do not know
> how many degrees they adjust the cam. If he is one tooth off, I am
> hopeful that he did not bend any valves. His head is uncut, so there
> may be enough room, but there sure would not have been on mine! Thanks
> list! I would do this all myself, but my engine is in pieces and
> scattered around in several places.
> Greg
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