ec 200 compression

[thejackrabbit]

i did a compression test on my 2006 ec 200, got 115psi
i added a little oil down the spark plug hole and got 120 psi

any one know what the spec is for compression is on the 200?

[nambo-trev]

Do a quick search for member wtec he had a thread 2 months ago on the 200 compression. I think it was around 165-180 if I'm not mistaken

[Jakobi]

Are you using a compression tester of known calibration? Using any adapters? And does it include the volume of the tubing/plumbing when reading? All these skew the reading big time.

I personally find it only to be useful for benchmarking. Ie once tested on a machine of known psi. I usually do a comp test on a fresh engine, and then a couple now and then if it feels like its falling down.

[Stoby]

That seems awfully low. To the point itd be hard -very hard to get started
Testers have lots of variables to skew actual readings. Whyd you test it?

[j_franich]

You may want to consider a leak-down test, and a vacuum test of the engine. These should tell you much more than a compression test, especially with the small volume of the cylinder.....and I'm assuming that you used the kick starter while preforming the compression test.

[Fred1956]

Originally Posted by j_franich

You may want to consider a leak-down test, and a vacuum test of the engine. These should tell you much more than a compression test, especially with the small volume of the cylinder.....and I'm assuming that you used the kick starter while preforming the compression test.

This is my preferred method....

[thejackrabbit]

The tester I used did have an adapter and a long (maybe 1 1/2 foot) tube, i used it on my kdx and got 105 before i rebuilt that and after a rebuild and RB head mods it was only up to 125

I also held the throttle open all the way and kicked it till it stopped going up

[Jakobi]

So its very likely that the compression tester is also working off the volume of the plumbing.

I usually don't even bother with doing comp tests to gauge piston/ring wear. I just do them at set hours, and then evaluate. No truer way than to pull the rings and measure the end gap. Then I determine if I can let them go longer next time or not. Usually do a piston at the same time for good measure.

Leak down testers will tell you a lot more about where you may/may not have issues.

As for spec on comp of the 200, it'll likely be lowish from the factory due to the large squish height/tolerances, and also depends on the base gasket stack.