hey i wanted to know if the compresion ratio on a 2.4l engine is supposed to be at 210 psi or if my car has had work done on it.
hope you guys can help thanks
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Thats a @!#$-load of compression. There is no way for a stock motor to have that high of compression.
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I believe it's a little high.
Cabon deposits can increase the compression a little.
J-Bo wrote:Thats a @!#$-load of compression. There is no way for a stock motor to have that high of compression.
That's not high. An Ho has 215 stock with 10:1 compression.
210 is what you want on the 2.4.
Gilles
2.3 Ho
compression tests are kinda pointless, do a cylinder leakdown test
btw with the leakdown test it tells you the percent of leakage from each cylinder so its alot more specific then com[pression tests and if you are losing compression the leakdown test will let you know where your losing the compression from, intake valve, exhaust valve, rings, ect..
Darkstars wrote:btw with the leakdown test it tells you the percent of leakage from each cylinder so its alot more specific then com[pression tests and if you are losing compression the leakdown test will let you know where your losing the compression from, intake valve, exhaust valve, rings, ect..
please elaborate good sir
compression test you crank the car over a specfic number of revolutions and what ever the cylinder PSI is it what it is.... all you can really check is make sure all 4 cylinders are near being the same or if the compresion has gone down., which isn't relaly allthat acurate anyway... an engine can be getting more wrn and losing some compresion but the carbon buildup on the pistons and in the the head take up space and cause compression ratio to go up slightly. It gives you a basic idea of whats going on but far from specific.
with cylinder leakdown test you 0 out the gauge then hook compreesed air up to this machine, once the cylinder is at TDC compression you hook up the little machine/gauge thing (not really a machine, just a bulky gauge set with air fittings) It knows how much air is being pushed in and instead of telling you how much compression it makes it tells you the % of the air that specific cylinder is leaking out. You can tell whats leaking by using your ear... if you have 50% leakage it will be obvious... open the trottle body and if you hear the air coming out the TB chances are you bent an intake valve, if you pull the dipstick and hear air coming out the dipstick chances are you fried the rings, if you hear it through the exhaust its somethign with the exhaust valve or valve seat ect... if you hear it coming out the spark plug hole form the next cylinder over you probobally have a blown head gasket. Its not 100% answers for all that stuff but it is very specific and will either tell you what the problem is or what to look for... example... hearing air out the dipstick doesn't mean it has to be rings, it could be a cracked piston but you knwo exactly what to look for after doing the leakdown test.
Hope that all made sence
heres a pic of the leakdown tester... hook it up regulate it to 100 PSI going into the cylinder and the other gauges shows the PSI its holding... 100 PSI in 80 PSI holding.... means 20% is leaking out
But the thing is an average joe doesn't have an air compressor and tank. then you need the $100+ leak down tester.
Compression test is more of a preliminary tool.
But yeah. Leak down>compression test.
