Help needed
Thread Starter
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Joined: Jan 2005
Posts: 4
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Help needed
i have a question
my father went to check the engine performance (outside the dealer )
of the mercedes E240
and the company evaluted the engine around 85%
so anyone here know how to compute the test ????
i have the readings as follows>>>>> with caps
ACTUATIONS COMPRESSION TEST:
CYLINDER: RPM:
1 231 rpm
4 234 rpm
3 234 rpm
6 231 rpm
2 228 rpm
5 230 rpm
so according to these readings what is the percentage of the engine ?
how to compute it???
what are the STANDARDS reading
engine :2400cc mercedes
thanks alot
my father went to check the engine performance (outside the dealer )
of the mercedes E240
and the company evaluted the engine around 85%
so anyone here know how to compute the test ????
i have the readings as follows>>>>> with caps
ACTUATIONS COMPRESSION TEST:
CYLINDER: RPM:
1 231 rpm
4 234 rpm
3 234 rpm
6 231 rpm
2 228 rpm
5 230 rpm
so according to these readings what is the percentage of the engine ?
how to compute it???
what are the STANDARDS reading
engine :2400cc mercedes
thanks alot
MBWorld Fanatic!
Joined: Jan 2004
Posts: 5,939
Likes: 178
From: Seattle WA
99 E320
i still dont have an answer for you. you may want to consider posting in the
more technical forums on the various MB boards. the folks cruising here are
more likely to have experience with accessories than engine tear down
skills etc.
in a nutshell, each engine has optimum PSI (pounds/sq inch) for the engine
when in perfect shape. in time, worn parts (valve guides, bad rings etc)
will cause the compression reading to become lower then that optimum
figure. if the figure is too low, it points to that single cylinder as suspect
and must be focused on...and to determine the cause of loss compression.
e.g. and pretending that your figures are in PSI measure
1 231
4 234
3 234
6 190
2 228
5 230
...means that #6 needs to be checked for crappy valve or rings etc
that figure would be approx 86% of the norm (relative to the other
figures). i find it interesting that the figures you provided just
happens to show that *all* of the cylinders are wearing so evenly that
they are all 85% of the normal compression reference point....unless
they are in great shape, well taken care of....and old. in other words,
it's in good shape, just a little worn....equally across all cylinders.
the figures are all balanced and doesnt cause any red flags to light up in
my brain. then again, i've never seen an RPM measure when it comes to
engine compression checks. i 've not heard of an ACTUATIONS
COMPRESSION TEST before.
http://www.mercedesshop.com/shopforum/
https://mbworld.org/forums/mercedes-tech-talk-41/
might want to try these places
more technical forums on the various MB boards. the folks cruising here are
more likely to have experience with accessories than engine tear down
skills etc.
in a nutshell, each engine has optimum PSI (pounds/sq inch) for the engine
when in perfect shape. in time, worn parts (valve guides, bad rings etc)
will cause the compression reading to become lower then that optimum
figure. if the figure is too low, it points to that single cylinder as suspect
and must be focused on...and to determine the cause of loss compression.
e.g. and pretending that your figures are in PSI measure
1 231
4 234
3 234
6 190
2 228
5 230
...means that #6 needs to be checked for crappy valve or rings etc
that figure would be approx 86% of the norm (relative to the other
figures). i find it interesting that the figures you provided just
happens to show that *all* of the cylinders are wearing so evenly that
they are all 85% of the normal compression reference point....unless
they are in great shape, well taken care of....and old. in other words,
it's in good shape, just a little worn....equally across all cylinders.
the figures are all balanced and doesnt cause any red flags to light up in
my brain. then again, i've never seen an RPM measure when it comes to
engine compression checks. i 've not heard of an ACTUATIONS
COMPRESSION TEST before.
http://www.mercedesshop.com/shopforum/
https://mbworld.org/forums/mercedes-tech-talk-41/
might want to try these places
Last edited by raymond g-; Jun 17, 2006 at 12:31 PM.
MBWorld Fanatic!
Joined: Mar 2006
Posts: 1,627
Likes: 5
From: West Virginia
2001 E320 RWD - Brilliant Silver/Ash: 100,000+
raymond g-
Originally Posted by raymond g-
i still dont have an answer for you. you may want to consider posting in the
more technical forums on the various MB boards. the folks cruising here are
more likely to have experience with accessories than engine tear down
skills etc.
in a nutshell, each engine has optimum PSI (pounds/sq inch) for the engine
when in perfect shape. in time, worn parts (valve guides, bad rings etc)
will cause the compression reading to become lower then that optimum
figure. if the figure is too low, it points to that single cylinder as suspect
and must be focused on...and to determine the cause of loss compression.
more technical forums on the various MB boards. the folks cruising here are
more likely to have experience with accessories than engine tear down
skills etc.
in a nutshell, each engine has optimum PSI (pounds/sq inch) for the engine
when in perfect shape. in time, worn parts (valve guides, bad rings etc)
will cause the compression reading to become lower then that optimum
figure. if the figure is too low, it points to that single cylinder as suspect
and must be focused on...and to determine the cause of loss compression.
Could RPM just mean the number of piston strokes per minute?
I agree with you about the PSI figures. Those are the only units that I've ever heard when measuring engine compression too.
