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Re: Midget's Compression "too" high?

Subject: Re: Midget's Compression "too" high?
From: (Mark Jurras)
Date: Wed, 1 Mar 95 15:31:42 EST
> I checked the compression on my Midget the other day. Due to a poor 
> performance I thought a burned valve would screw up the compression. So I 
> found:   (front)  1    2    3    4  (rear)
>                  185 200+  180  190 psi. 


When performing a compression test to check an engine's condition, it
is not the actual numbers you get but how they relate to one another
and how you get them.

For an engine in good condition the low cylinder is about 95% of the
high cylinder. A tired engine the low will be 70% of the high.

When performing the test, remove all the sparkplugs. Connect the
compression tester and crank the engine and watch the gage for four (4)
puffs.  If the first reading is low and stays there for each additional
puff a valve is bad. If the reading on the first puff is low and
gradually builds to the final reading with each puff your rings are
bad, you have a leak in the head gasket or a crack. To verify the rings
are bad. Put three (3) squirts of engine oil from a plunger type oil
can into the cylinder and retest. The gage will pump higher on the
initial puff and not gradually increase as before if the rings are bad.

As for your high readings my GUESS is that you either have very high
compression of a lot of carbon built up inside.

Comments Welcome!

- -Mark     = =o&o

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