compression test

so when i do a compression test do i pull a plug put in the tester and let
the engine run normally on 3 or just do it cold with the starter or hand
turin it or what

newbie wrote:

> so when i do a compression test do i pull a plug put in the tester and let
> the engine run normally on 3 or just do it cold with the starter or hand
> turin it or what
>
>
>
All 4 plugs out.
Hold throttle & choke open (just to let air in).
Use starter to crank several revs.

Oh...you'll need long arms to reach the Ignition key...

Unless you've already had the plugs out before,
consider that there is *some* risk of one of them
stripping threads out of the head:-(

I always weigh this factor when deciding whether
a compression test is really needed.

You can get a fair idea of compression just by
turning the crank pulley by hand. If you turn it
2 revs, you will hit all 4 compression strokes.

Speedy Jim
http://www.nls.net/mp/volks/

Turn over with starter at least three compression strokes of that cylinder,
compare all four. The thumbrule says compression within 10% of each other.

In article >,
> wrote:

> Turn over with starter at least three compression strokes of that cylinder,
> compare all four. The thumbrule says compression within 10% of each other.

Last summer when I checked mine, I was getting fairly consistent across
all cylinders, but only about 125 PSI instead of a nicer 140 PSI... How
bad is that? I'd love to have the max. power I can get but I have to
weigh it against disturbing an otherwise smooth running motor.

It's my original 40 HP 1200 motor, but with a Sears rebuild
pist/cyl/rods/valves/bearings upgrade done years ago that supposedly
turned it into a 1300 cc motor in the process. I remember being able to
chirp the tires, but back then I had bias ply on the back, not the
current radials... is that a crucial difference perhaps?

--
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|___| '61 - VW
(o\_|_/o) Bug! ALEA -- 35.9 BHP and not a bit more!
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