Hi Joe,
Glad somebody commented! I'm as nervous as a mother hen about running the
thing. Somewhere I read that you can check for spring bind by making sure a
paperclip fits between the coils at full lift. Seems crude, but the paperclip
fits. Any idea on an actual measurement with a feeler gauge?
Dave
Joe Curry wrote:
> Dave,
> With all the work you have done, make sure that your valve springs are
> not coil binding. That will stop them from opening up all the way and
> could be responsible for the noises.
>
> Joe
>
> Rivendell wrote:
> >
> > I need some serious gearhead help for this one...
> >
> > After 10 years of restoration work, I finally managed to drive my TR4A
> > to the end of the block and back yesterday. No hood, interior, tranny
> > tunnel, guages, etc., etc., but it still made it. This is also the
> > first time the rebuilt engine has been run.
> >
> > One of the first things I noticed (after I got the exhaust to work) was
> > the incredibly noisy tapping from the valve train. First step was to
> > check rocker clearances; all are at 0.010" cold. Now is where it gets
> > tricky...
> >
> > The head is shaved 0.080". I'm also using a shim steel head gasket from
> > Ken Gillanders at BFE, as well as a performance cam from him (don't
> > remember the specs off the top of my head). I'm also using his heavy
> > duty competition valve springs, along with the lightened aluminum (?)
> > retainers. Also using his chrome-moly pushrods. I thought that I had a
> > standard pushrod length, so my first guess what that I had to turn them
> > down a bit to make up for the head shaving. However, when I measured
> > one, I found that I actually have 257mm pushrods (roughly 10.125") and I
> > believe the standard pushrods are 260mm (roughly 10.25"). I don't
> > remember ordering shortened pushrods, but that was a long time ago and
> > my record keeping isn't what it should be. This may actually be too
> > short based on what I took off the head, but I would welcome comments.
> >
> > I'm using the standard shaft, with the standard rocker arms. I didn't
> > rebuild it (yet). I pushed a few of the rocker arms up and down the
> > shaft to check for wear, and I can see some discoloration on the shaft,
> > but it is not enough to catch my fingernail on. I'm thinking that this
> > should be servicable for now, and shouldn't be causing that much noise.
> >
> > Next I checked the valve at half-open according to the competition prep
> > manual. The manual says that "the axis of the valve stem and the rocker
> > arm should be at 90 degrees to each other, and the rocker arm tip should
> > be centered on the stem" or something like that. Problem is, this is
> > just about impossible to eyeball, but it looks right.
> >
> > So, where is all that noise coming from? I think I've ruled out a worn
> > rocker shaft, and I also think I've ruled out bad rocker geometry (I've
> > been wrong many times before, though!). Are those heavy-duty valve
> > springs along with the high-lift cam making everything noisy? Are the
> > pushrods too short? Is there a better way to check the geometry?
> > Should I shim the pedestals? Will it just go away over time as the
> > engine breaks in?
> >
> > Sorry for the rambling, but this one has me stumped. All responses
> > welcome.
> >
> > Thanks,
> >
> > Dave Rupert
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