1996 Legacy Outback 2.5L Low compression in 3 cylinders after head gasket replacement

Ok, so I've been working on this car for several days now changing the head gaskets for new Felpro ones.

*CAR RAN BEFORE HEAD GASKET REPLACEMENT*

Everything was going well until I went to turn the key and all it does is crank. So I started diagnosing everything.

Spark: Good, checked a grounded plug and it fires away

Fuel: Good, injectors connected properly, spark plugs have fuel on them

Timing: Checked it, re-checked it, checked it again, and then did that sequence 5 more times. Timing mark on crankshaft lines up with the mark on the CPS, cam pulleys line up like: (LI=Left Intake RE=Right Exhaust)

|---------------|

LI-------------RI

||--------------||

||--------------||

LE-------------RE

|---------------|

Compression was checked multiple times, holding the throttle at WOT:

#3=35psi----#4=30psi

#1=32psi----#2=200psi

"AHA!" I said to myself. Well, actually it was more like "F***ingsonofab**ch WHY ME", but that's neither here nor there...

Ok, so from my research, timing being off or valves not completely closing could pretty much be the only thing that would do this. However, the 200PSI in cylinder #2 is throwing me off. If timing was off, and #4 is low, wouldn't #2 pretty much HAVE to be low, considering they share the same cams?

So unless I've overlooked something, it seems to me that it is valves not closing properly. The ONLY thing I didn't do by the book is I accidentally mixed up the tappets, so they did NOT go back into their respective homes. I know I messed up there because of possible wear patterns, but AREN'T THEY ALL THE SAME THICKNESS?

My question is, have I overlooked something? I should say, I do not have access to a leakdown tester, and have $0 to get one, so while I KNOW I should perform one, I just can't.

PLEASE, if you can think of something else I can check, TELL ME!! I have run out of options.

The ONLY thing I didn't do by the book is I accidentally mixed up the tappets, so they did NOT go back into their respective homes. I know I messed up there because of possible wear patterns, but AREN'T THEY ALL THE SAME THICKNESS?

That could be your problem. The shims are not the same thickness, every one of them in there could potentially vary in thickness.

You'll need a feeler gauge to check for proper gaps and, to correct them, you'll need a micrometer. You might be able to get by with an accurate set of calipers but they won't be near as accurate as a micrometer. You should at least be able to get it close enough so that all the gaps are correct.

I'm not sure though that they would cause such different compression results though. The shims would have to be thick enough to cause a valve to always be open. Like I said, it could be possible but only testing would tell. I would check valve clearance to be on the safe side though.

Ok, so a quick update: I checked the cam to valve clearances and they are as follows: (#1INV1 means cylinder #1/Intake/Valve nearest to front of car. #1INV2 is the one next to it.)

#1

INV1= touching ( meaning there is no room for even the .0015" feeler gauge)

INV2= .005"

EXV1= touching

EXV2= touching

#2

INV1= .005"

INV1= touching

EXV1= touching

EXV2= touching

#3

INV1= touching

INV2= touching

EXV1= touching

EXV2= touching

#4

INV1= .008" (perfect!)

INV2= .008" (perfect!)

EXV1= touching

EXV2= .008" (only .002" out of spec)

See how #4 is adjusted much better? Thats the cylinder I got 200psi of compression on, remember?

Ok, so now my next question: I have the 1996 DOHC EJ25, I have CONFIRMED that it has Hydraulic Actuated Lifters and NOT the "shim over bucket" mechanism...How can I adjust these lifters?? There MUST be a way, even if it means removing the cams and trying to find each bucket's "old home". Is that the only way to do it? And how will I be able to figure out which one goes where??

Ok, it seems like most of the the hydraulic lifters are stuck in the "compressed" position. I pulled two out, and freed one hydraulic actuator. Here is a comparison shot:

http://i157.photobucket.com/albums/t57/sly1685/photobucket-4258-1323116431915.jpg

The one on the left is a stuck, compressed lifter, while the one on the right is functioning properly. However, this is bothering me, and this job has been so frustrating that I might not be thinking correctly, but wouldn't a "compressed" lifter make a valve stay SLIGHTLY MORE CLOSED, rather than open?

Hmm... since it has HLA's they should self adjust for the proper clearance. Unless they use two different types with different thicknesses for intake and exhaust it shouldn't be that far off. I'll see if I can find anything in the FSM about differences in the thickness of them between intake and exhaust.

Edit: If they aren't "compressed enough" I could see them keeping the valves open. I'll have to check the FSM some more and see if they are self bleeding or if you can manually bleed them. That sometimes helps get them working smoothly again.

All the HLA lifters are exactly the same, for the intake and exhaust. I had them out when I did my head gaskets recently.

Being collapsed will cause LOUD clicking noises because of the cam shaft slapping away at it when the lobe comes around to push the lifter in order to open up the valve. There is no way to actually adjust the lifter. They are self-adjusting. HLA stands for Hydraulic Lash Adjusters. All the lifters that are stuck in that position (the way the lifter on the left looks) are *either compressed or collapsed. If you let them sit upside down in some fresh oil you can can tell if they are just compressed or collapsed by looking for dirty oil to starting penetrate into the clean oil. If they are collapsed, they need to be taken apart, cleaned, put back together, and soaked in oil.

This will NOT cause low compression.

BUT

If the lifter isn't properly compressing (they are supposed to compress ever so slightly when the cam lobe pushes it down) or allowing oil back inside the lifter, as the cam lobe continues on, the valve will not be closed all the way. This is because the lifter is stuck in it's hardest position because the check ball inside the lifter isn't allowing oil in or out of the lifter. Just one of the four lifter in any given cylinder can keep the valve open just enough to where you won't have much compression.

I'm pretty sure I can bleed them manually, I just did two to make sure I could, then started taking off the rest of the camshafts.

The problem seemed to be that they were stuck in the fully compressed position...which would make the valves err on the side of staying closed instead of open. I can't figure it out, but I DO know that them being stuck is something I can fix and its about the only thing I can find wrong.

All the HLA lifters are exactly the same, for the intake and exhaust. I had them out when I did my head gaskets recently.

 

Being collapsed will cause LOUD clicking noises because of the cam shaft slapping away at it when the lobe comes around to push the lifter in order to open up the valve. There is no way to actually adjust the lifter. They are self-adjusting. HLA stands for Hydraulic Lash Adjusters. All the lifters that are stuck in that position (the way the lifter on the left looks) are collapsed. They need to be taken apart, cleaned, put back together, and soaked in oil.

 

This will NOT cause low compression.

 

BUT

 

If the lifter isn't properly compressing (they are supposed to compress ever so slightly when the cam lobe pushes it down), as the cam lobe continues on, the valve will not be closed all the way. This is because the lifter is stuck in it's hardest position because the check ball inside the lifter isn't allowing oil in or out of the lifter. Just one of the four lifter in any given cylinder can keep the valve open just enough to where you won't have much compression.

So far they have all been stuck in the fully compressed position. I haven't gotten to cylinder #4 though, I'm curious as to whether THOSE are stuck...

I'm pretty sure I can bleed them manually, I just did two to make sure I could, then started taking off the rest of the camshafts.

 

The problem seemed to be that they were stuck in the fully compressed position...which would make the valves err on the side of staying closed instead of open. I can't figure it out, but I DO know that them being stuck is something I can fix and its about the only thing I can find wrong.

this >>

If the lifter isn't properly compressing (they are supposed to compress ever so slightly when the cam lobe pushes it down) or allowing oil back inside the lifter, as the cam lobe continues on, the valve will not be closed all the way. This is because the lifter is stuck in it's hardest position because the check ball inside the lifter isn't allowing oil in or out of the lifter. Just one of the four lifter in any given cylinder can keep the valve open just enough to where you won't have much compression.

How are you bleeding them? If you are compressing them without releasing the check ball or taking them apart, you should not be able to do this and this means they will NOT function properly and will just collapse again.

If this is the case they need to be taken apart one by one and cleaned.

http://forums.probetalk.com/showthread.php?t=1701019093

I pulled the actuator out of the lifter, put them into a container of clean engine oil, then pushed the ball valve down and compressed them 20+ times or so, flushing the old, dark oil out and sucking the new clean oil in. Then I released the ball valve and pushed down on it again, "setting" the valve so to speak.

I then filled the lifter reservoirs with clean oil and I'm preparing to swiftly put the actuator into the lifter without letting any oil leak out, and then install them again, keeping the reservoir hole pointed up the whole time so no air gets it. Do you think this will be good enough? I don't see the reasons behind completely disassembling them when they obviously compress and spring back in the pan of oil.

The funny thing is, the ones that measured "good", mostly in cylinder 4, were the ones that had air in them...the vast majority of them were filled completely with oil like they are supposed to be! I'm so confused by this...

Before you install them, it is very important to let them soak (submerged) in oil over night regardless of how quickly put the actuator in the filter.

The reason I say completely disassemble them, is because it's not that hard and I always say it's better to be safe then sorry. I'd rather do it all at once instead of guessing or assuming.

And when you say they had air in them, were they compressed or uncompressed?

Either way they are supposed to have some oil in them. If they were compressed and had air in them that just means that they are collapsed.

The others, that had oil in them.. Where they compressed or uncompressed?

If they were compressed that means the lifters aren't working properly and won't uncompressed

Also, I just realized I left out a few descriptive words in my first post. I edited with an asterisk in front of the added few words.

Before you install them, it is very important to let them soak (submerged) in oil over night regardless of how quickly put the actuator in the filter.

 

The reason I say completely disassemble them, is because it's not that hard and I always say it's better to be safe then sorry. I'd rather do it all at once instead of guessing or assuming.

 

And when you say they had air in them, were they compressed or uncompressed?

 

Either way they are supposed to have some oil in them. If they were compressed and had air in them that just means that they are collapsed.

 

The others, that had oil in them.. Where they compressed or uncompressed?

 

If they were compressed that means the lifters aren't working properly and won't uncompressed

 

Also, I just realized I left out a few descriptive words in my first post. I edited with an asterisk in front of the added few words.

The ones that had air in them were NOT compressed, I could push on them and they would push in very slightly, then rebound. The rest of them were stuck compressed. I say *stuck* but from what I can tell, they should push back out with oil pressure in the reservoir hole. So now that I'm getting more and more in depth with these, the more I see that perhaps they weren't bad at all.

But why were my valve clearances so tight????? Its like they were stuck open...BUT THEY WEREN'T! Everything makes sense up to that point, then my head starts to hurt wondering just what exactly it is that I want them to do...

The funny thing is, the ones that measured "good", mostly in cylinder 4, were the ones that had air in them...the vast majority of them were filled completely with oil like they are supposed to be! I'm so confused by this...

That actually makes perfect sense. The ones with air would have kept the valves from opening all of the way but would have sealed tight when closed. The ones with full pressure would be much more likely to hold the valves open if there was "too much" pressure. Seems like the case, hopefully this works out for you.

That would be why there was definite compression in cylinder 4. The lifters were basically collapsed, allowing the vales to be completely closed. This was probably because they were allowed to bleed when you initially had them out and were not soaked in oil before being put back in. Either that, or they got crap in them and oil was unable to find it's way back in. I would put money on the latter considering that you had every lifter out and the only ones with air were in the same cylinder.

Just to be sure, when you say, "cam to valve clearance" you are talking about the space in between the cam and The camshaft is actually supposed to be touching the tops of the lifters. If not, this means they are collapsed.

To define what I mean when I say collapsed, I am saying that they are just not functioning properly. In this case they can be fixed, but if they are actually collapsed that is a spring failure and that can not be fixed. In your instance, I don't believe that is the case.

At this point, I'm going to say that you may have bad lifters that aren't compressed properly or you have a timing issue wherever it may be.

So what you're saying is that there is supposed to be NO clearance between the cam lobes and the lifters? Why does the manual say .008" for intake and .0010" for exhaust clearances then? Is that a different clearance?

BTW, thanks for the replies everyone, I really appreciate your help.

It must be for something different. I've had 3 engines apart recently and never had any clearance between the cam and lifters.

What manual is this? If it's the Haynes or factory service manual, what section/page? I've never seen any clearance information for this in it..

I had no clearance, I'm thinking that this is normal for HLA engines. I went and looked at the Hayes manual I have for the vehicle and I NOW see that on page 1-26 its states "Valve clearance check and adjustment (1997 and later models)"

I should have paid more attention.

Anyway, I think I have figured out this mystery. I actually figured it out much earlier, but didn't realize it. I was only getting around 30PSI on three out of four cylinders, right? Ok. The whole time I'm wondering, if the HLA's stuck in the "collapsed" position, why would the valves stick OPEN? It seemed more likely that they would stay CLOSED...anyone see where I'm going with this?

They DID. All the clues were there...IME if a valve is stuck open, there will be 0PSI in that cylinder, not 30-35PSI. Not only did the EXHAUST valves stay shut, SO DID THE INTAKE VALVES. Which would lead to not a lot of air getting in...say, around 30PSI or so!

Cylinder #4 did just fine, why is that? Well, #4 had air trapped in the HLA's, causing them to not function PERFECTLY, but at least enough to NOT STICK in the collapsed position! Which made them continue to work ok, although they would doubtless have been noisy if the engine had actually ran.

I think the reason why most of the HLA's got stuck is because most of the oil in the reservoir leaked out, leading them them not having enough oil pressure to push back out to their fully extended position.

What do y'all think of this theory of mine?

Got everything back together last night, new compression test results:

#1 205PSI

#2 207PSI

#3 195PSI

#4 30PSI

:tearshairout:

Time to tear it down again. I don't know what could be the problem in that cylinder, apparently the problem WAS the HLA's, but they all got the exact same treatment, so why is cylinder #4 still low? I'm starting to get tired of taking this engine apart and putting it back together.