2G Low compression cylinder #1

[mcfeat96talon]

Here it is, I put crower 272 cams in my 2g, i also installed topline revised lifters. With everything installed, cylinders 2,3,4 are excellent on compression. Cylinder 1 is low. Did a leak down test, intake valves are leaking. Removed the head took it to a machine shop, checked out fine. Re-installed everything, still low compression. found that the lash adjusters were holding the valves open once they are pumped up. I bled them all again, tested the compression and everything was great. BUT once the lash adjusters were fully pumped up again, low compression in cylinder 1, and only in cylinder 1.

Could there be some issue due to the lash adjusters recieving oil starting at #1 cylinder? I have literally tried everything I and many others can think of and still the same problem.

I have tried switching cams back to stock. Lifters back to stock, bled lifters at least 5 or 6 times, I'm at a stand still.

Any suggestions would be greatly appreciated!!!!!

 

[eburg2490skillz]

Have you taken the block out and checked the piston? check the rings and oil clearence. make sure that the rings are staggered! this can blow by and drop in compression. any sounds while driving before you did a cylinder leak down test? is the deck warped at all?

sorry i skimmed through your thread too fast and missed out on a lot. a machine shop would have checked for alignment, clearence, condition and warpage so that cancels out my previous post. check your cam lobes and see if your timing is correct. what all did the machine shop inspect?

 

[mcfeat96talon]

They took 5k off the head, checked for leaking valves, and cracks and such. At first when the lifters are bled it has perfect compression, only when the #1 cylinder lifters are pumped up, does it then loose compression. Is there any chance it may have to thick of motor oil in it? The last time I ran it was during a 95 degree day an I had I believe 20w 50 in it. I know that way to heavy but track temperatures were in excess of 110 so...

 

[Metal Health]

Change oil to stock, run it long enough for new oil to work into lifters. Take a good casual ride, comp check it.

 

[007jimmy]

have you checked for foreign material in the lifter socket or there is something clogging the pressure relief hole just left/right of the lifter. with the lifter removed you can dump oil down there and then push the lifter back in. oil should come shooting out that small hole next to the lifter... also did you upgrade your valve springs when doing the cam. they could not have enough pressure to push the lifters shut. have you tried swapping parts around to different cylinders to see what part follows if any. try the lifters first, then the rockers, then the valves and spring. If it ends up being the lifters i have a full set of geniune mitsu lifters off an evo 9 and evo 9 behive springs with titanium retainers.. let me know if your interested. selling them cheap.

 

[weebz1]

i second checking the springs if you haven't done so already. . had a buddy who was losing compression and turned out one of his springs snapped and didn't notice it until he realllly took a look at them as it just fell down inside the lower half of the spring give them a good look over.

 

[mcfeat96talon]

The Problem is localized to cylinder 1. I have BC springs and retainers in it, the lifters and rockers have all been switched around already. I took it down the road Saturday, after changing to stock oil, thought it may help running it a little. Didn't help at all. Checked all the springs they seem to be good. I currently swapped back to the stock head and once again no luck. Could the check valve in the oil pump be brocken or maybe stuck shut making pressure to high at low RPM?