You need to do a leak down test then to check to see if the valves are leaking. You will need a leak tester like this one or something similar. http://www.matcotools.com/catalog/pr...R-LEAK-TESTER/
You will have to remove the spark plugs and start with number 1 cyl at top dead center. Then follow the firing order with that piston at top dead center. Anything more than 20% leakage is usually not good. 15 is about avg and anything lower than 10 is very good.

 

Its your HG. Your comp readings tell you. 120 at cyl 2 and 3. Anytime you have neighboring cylinders with low readings indicates a bad HG. Not sure why you torn down the upper end and re-used the stock gasket again. If you want to do a test on the valves turn the head over and fill each chamber with water. If the water leaks out it will leak out the bad valve. Hope this helps.

 

I did put on a new head gasket. Then when I put it all back together the compression test read the same. Give or take a psi or so. Also I checked the to bad cylinders and they didn't leak at all. So the rings are still good. So this leads me to believe that the valves are bad. Floated or bent valves.

 

On a 2.4 what should be the compression? 10:1 Manley pistons and rods.

 

well if ur headgasket is bad then chances are some oil might have contaminated the coolant. A simple test most auto parts stores carry is a dye kit that you suck up some coolant from your radiator put this test kit in the coolant, and if it changes color then oil has contaminated it. Well a couple other things it could possibly be is not fully seated valves. When you put the head back together did you check the valve guides make sure there not excessively worn cuz if so then your valves could be moving more then oem specs allows which wouldnt completely seal the combustion chamber. Now when you did your compression test, you did it after it was up to operating temp right? And made sure you had the gas pedal all the way down during the cranking process right? Now some people have had issues with doing that test and the starter after going to #2 or #3 test, sometimes the starter doesnt have enough juice to fully crank over, so have a battery charger hooked up to your battery to make sure its getting ample cranking during your test. Good luck id put my money on either bent valve like you said, maybe worn valve guides, or maybe you installed some keepers wrong on the valve spring/retainers. Good luck. Hope I helped ya.

 

Thanks for your write up. I am going to take my head off and have it tested. Plus put in some supertech valves. Friend works at a machine shop so I can get it all done at a good price. Then I'll have supertech valve components in the head. This isn't my d/d car so I will be ok.

 

compression check can tell you that something is wrong but not really the greatest test. do a cyl leakdown. from there you can tell if its an exhaust valve, intake valve, headgasket, or rings

 

+1

 

You do the test warm or cold? More then likely its your headgasket. It could be a warped head or block though too. Rarely do you bend valves in 2 cylinders and not the other 2.

I'm assuming when you did the headgasket you torqued everything to spec and the right order?
Having a clean surface is very key on 2.4's, what HG you use anyway?

 

I ordered the hg through Buschur. I did the torgue in order and to arp specs. We checked the head it wasn't warped. And this motor has never over heated. This build has only a few 1000 miles on if even that.

 

Oh yeah on another note. I think my timing is off. And that is what bent my valves. When I checked the compression it was lower than before across the boards. Doing the timing on these 2.4's are a pita.

 

Probably your piston rings. Setting the timing on a 2.4 is no different than the 2.0L other than degreeing the offset for the higher deck height.

 

Not the rings I put ATF in the cylinders and let it sit. None leaked out. So the rings are holding.

 

stop guessing and using pointless tests like putting oil on your piston tops. put everything together. warm up engine. sent cyclinder you are testing to tdc. then pressurise with leakdown tester. where the air comes out is where you have a leak. if you have bent intake valves you will hear the air coming out your intake. if you have bent exhuast valves you will hear it in your exhaust. if you have a bad head gasket you will see bubbles in your radiator and if your rings are bad you will hear the air from your crankcase vent tube or dipstick(depending) simple and a definitive answer.

 

great answer up above..quick question guys not to threadjack but do you guys do a leakdown test on a warm motor? will the results vary on a warm and cold motor? and what are the normal leak % for the two i know i seen a post up above..Also compression is only done on warm engine correct? thanks and sorry for all the questions.