Subject: Valve springs--the saga continues Subject: Valve springs--the saga continues Subject: Valve springs--the saga continues

[Jon Pike <jhpike@domain.elided>]

> Okay, I made a little thingy for the spring compressor to hinge on 
> that will bolt on to the cam bearing thingies (I still don't know 
> what I'm going to do for the exhaust valves), but now I have a new 
> problem.  I had planned on pressurizing the cylinders to keep the 
> valves up, using the little hose from my compression gauge.  However, 
> it seems as though the hose has a one-way valve in the end, so this 
> totally won't work.  My question for the collective wisdom of the 
> digest is: is there a way to jam this valve open without breaking 
> anything, or is there another readily available piece of equipment I 
> can use to attach the air compressor to a spark plug hole??
Aha..  thanks for informing me of a problem I would discover later..  I 
was contemplating buying a leakdown test fixture.. it was going to 
include a gauge and cost a lot..  Then I realized my ancient compression 
tester had a quick disconnect fitting in the middle of it's hose..  that 
fit a hose I have on a CO2 cylinder with regulator I use as a compressed 
air source.

But you're right.. I haven't tried using it yet,  so I hadn't noticed. 
If I remember right there might be a bicycle tire valve in there for 
the one way,  and you could carefully unscrew the valve body and have 
just a thru pipe.

Hmmm..  just went to the garage to look.. mine has no valve at all,  in 
the lower half anyway,  except for a bike valve type up in the gauge 
body to relieve pressure after testing.  
Hope your's does have a removable valve,  otherwise finding some kind of 
leakdown fixture should do it for you.  Whether the pressure of your air 
on the valve head will be enough to hold the valve closed against the 
spring remover might be another story..   Try calculating the square 
area of the vavle head,  against the PSI you will apply,  and measure 
that against the spring tension to see if you will have more force 
holding it closed,  or not..  Do that first...  since the whole idea 
might not be feasable,  and then you're wasting your money buying things.  
Wasn't there a "feed rope into the cylinder so the valves are braced at 
TDC" technique?

Jon
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