Refreshing the engine (rebuild and aftermath)

If the engine has quieted down since that video was taken, then perhaps it was just due to the lifters not being "pumped-up" yet. If however it still sounds the same, then there is a problem. These are hydraulic lifters and there should be zero lash. This means there should never be any space between a lifter, a push-rod, the rocker arm or a valve. Matter of fact, there should be about .090" pre-load on the "self adjusting" piston inside the lifter. If the lifter is at the base of a lobe and you can move/rattle a rocker arm by hand (in it's normal direction of travel), then there is too much slack and something should be done to correct it.

When I said possible machining error I was refering to things like decking the block, shaving the head, grinding valves, etc. If the camshaft is new, then it's very unlikely it's defective (it's almost unheard of to see machining errors on these type parts). Still if you have excessive valve noise, part of the troubleshooting process is to rule things out. Cam lobe condition and lift can be checked with engine assembled if you have the proper instruments. If you don't have these things they can be picked up on Amazon and eBay for a reasonable cost (your time is likely the bigger investment). I use a dial indicator with a long extension. I have a mount bracket I made to bolt the mounting arm to the engine and it can be adjusted into place for each lifter. Specs for the camshaft are in the service manual. Tim

Finally got around to the van again. And you are absolutly corret Tim, the push rods are all to short. OEM are 6.380" in length all of mine are roughly 6.366 to 6.368". I think I am going to just order new OEM push rods and hope that does it.

http://i.imgur.com/bGhJw3s.jpg

did the longer push rods fix your problem?

That is way noisy. I have had about 8 different Vans and not heard a 4Y sound like that except for really cold starts and lasting about 10-15 seconds and that is on high mileage engines. Kind of reminds me of the sound a playing card would make in the spokes of a bicycle wheel

Push rods finally came in; no difference. I shot another video of the van idling. It's just as loud and sputters a lot.

https://youtu.be/JzaNu79J6KU



After running for a few minutes I noticed the low coolant light was on. And, well this is what my oil looked like:

http://i.imgur.com/Nn46OVj.jpg


It wasn't there the last time I worked on the van. I checked compression on all 4 cylinders and it's around 130psi on each one so I didn't blow a head gasket. But it's getting in there some how. I changed the oil and filter with some cheap crap just to flush it. I also took the valve train out again to inspect the rocker arms and shaft. The shaft had a lot of debris and gunk built up inside it so I cleaned it with mineral spirits and put it back in. I have installed the valve train so many times I have a pretty good system now. I ziptie the rocker arms together to keep them where they need to be on the shaft and then bent a bunch of old wire to hold the push rods in place. It works like a charm and makes the job really simple.

http://i.imgur.com/ETZGGCi.jpg

http://i.imgur.com/To2Hd8c.jpg

I don't really know where to go from here. I have replaced and checked everything in the valve train at this point and the problem is still there. Plus now I have coolant leaking into the engine. I have had pretty bad luck with this van and the idea of cutting my losses and selling it may have to be an option. I have sunk a lot of time and money and I don't want to have to do that, but I don't have much time or money to throw at it anymore.

I'm very sorry you're going through this. I know what a disappointment it must be. If you had this professionally rebuilt, then this should be on them...........all of it. I suspect the coolant in the oil is most likely due to a crappy aftermarket head gasket, but it could also be due to it overheating (I recall you saying earlier it was getting extremely hot). Other ways coolant and oil can mix is crack(s) in the head or casting flaws (if it's a new one). Another thing that can happen is cracks or pinholes in the block between the water jacket and the cylinder bore(s). That last one is not uncommon on some high performance engines, but I've never seen it on a 4y. The 4y is a heavy duty industrial quality engine so I don't think that's likely. Still, if there was a casting flaw, and the block was bored, it's possible a breach could have occurred.

Regardless, whatever the reason, none of your options are that great. With all these issues, it it were mine I'd probably pull the entire engine, disassemble, and go over everything with a fine tooth comb. If I had paid somebody to do the work and they wouldn't make it right, I would probably return the engine to them via a trebuchet (not advocating any violence here).

As for your push rods, when you posted above I was afraid the old ones were not off far enough to make a difference, but without measuring/checking all parts & geometry before making changes it's all random (it's better to measure twice and replace parts once). Tim

Terrence

You mentioned that you were getting 130 PSI compression on each cylinder. 128 psi is the minimum. The spec range is 128-178 PSI I would expect a newly rebuilt engine to have at least 175 PSI per cylinder. I would think faulty head gasket is the cause of the low compression uniform in all cylinders and thus coolant getting into the oil

Quote:

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Originally Posted by timsrv

I'm very sorry you're going through this. I know what a disappointment it must be. If you had this professionally rebuilt, then this should be on them...........all of it. I suspect the coolant in the oil is most likely due to a crappy aftermarket head gasket, but it could also be due to it overheating (I recall you saying earlier it was getting extremely hot). Other ways coolant and oil can mix is crack(s) in the head or casting flaws (if it's a new one). Another thing that can happen is cracks or pinholes in the block between the water jacket and the cylinder bore(s). That last one is not uncommon on some high performance engines, but I've never seen it on a 4y. The 4y is a heavy duty industrial quality engine so I don't think that's likely. Still, if there was a casting flaw, and the block was bored, it's possible a breach could have occurred.

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Quote:

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Originally Posted by timsrv

Regardless, whatever the reason, none of your options are that great. With all these issues, it it were mine I'd probably pull the entire engine, disassemble, and go over everything with a fine tooth comb. If I had paid somebody to do the work and they wouldn't make it right, I would probably return the engine to them via a trebuchet (not advocating any violence here).

As for your push rods, when you posted above I was afraid the old ones were not off far enough to make a difference, but without measuring/checking all parts & geometry before making changes it's all random (it's better to measure twice and replace parts once). Tim

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Quote:

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Originally Posted by JPERL

You mentioned that you were getting 130 PSI compression on each cylinder. 128 psi is the minimum. The spec range is 128-178 PSI I would expect a newly rebuilt engine to have at least 175 PSI per cylinder. I would think faulty head gasket is the cause of the low compression uniform in all cylinders and thus coolant getting into the oil

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That's my suspicion as well, so I pulled the cylinder head...

http://i.imgur.com/gHtWSBL.jpg


I don't see any immediate issues in the head gasket (other than it needs to be replaced now) but I also haven't checked the head for any cracks or warping. While I have everything apart again I am going to just bite the bullet and replace the rocker arms and shaft since everything else in the head is new. As well as there was some scoring on the shaft from oil starvation. I think I will pull the crank shaft and check to see if it's the correct one since the builder installed it when the motor was rebuilt.

One thing that really caught my attention when I pulled the head was that there is a lot of carbon build up on the pistons for a motor with only 600 miles on it. I think that it may be from the valves not opening all the way if the lifters weren't function correctly, but I could be wrong. I am also going to replace the radiator while I'm in there and put in an oem thermostat since it over heated the last time I drove it and it has me concerned.


http://i.imgur.com/G9kkxY4.jpg

http://i.imgur.com/W8or94x.jpg

Well, it's been awhile but I finally ordered parts and tried my luck at this van again.

I ordered a Chinese made cylinder head off ebay from a reputable seller since it came with valves, valve springs and all new rocker arms and shaft installed. Everything looked good on it and overall I was pleased with the head.
The only issues I ran into were the holes for the exhaust/intake manifold studs were off just a hair and I had to enlarge the hole on the manifold to clear the studs. Also a hole for one of the fuel lines was missing but it's secure enough for it not to be a concern. I replaced all the gaskets and installed a Toyota head gasket this time around.



http://i.imgur.com/N3znLjS.jpg



After new filter, oil and coolant I fired it up. It hesitated but finally ran. And... nothing changed. Same noise coming from the motor, same sputtering at idle. Only thing that has changed is that the oil is clean of coolant. I let it run for 5 minutes and it never got quite or anything else. So I let it sit for a few days out of frustration. Went to start it again to check compression and now it won't run at all. Cranks all day but won't fire. Timing may be off but I'm pretty well fed up with this thing. The only thing I haven't replaced or checked in the valve train is the camshaft which the engine shop said they replaced. I guess all I can do is check timing, compression and after that I am out of ideas honestly. Such a bummer.

Quote:

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Originally Posted by timsrv

Flat camshaft? Check travel with a dial indicator. Also, make sure the rocker shaft is right side up.

http://www.toyotavantech.com/forum/s...roubleshooting

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Bringing back this thought, but how would you go about measuring the travel exactly?

It's a shame you had the head off and didn't do it then (easy). It can still be done, just a bit more complicated. I'd pull the rocker assy back off, then use a dial indicator on the push-rods while rotating the engine by hand (removing spark plugs will make rotation much easier). Cam specs are in the FSM. Tim

Could I not just do it on the rocker arms? The clearance should be the same since they are on the pushrods.

You could, but there will be the variable of the lifters potentially compressing with the spring tension and the lack of oil pressure. It would be more accurate to take the load off the lifters before measuring.

Aww, that does make since. Alright I'll give that a go.

Sucks having the van sit while you bang your head against the wall over and over like that - keep at it and it will all be worth it once its running again :thmbup:

The only specs I could find for the Cam are the lobe height. I can only measure the lobe lift.

Edit: Well, I found online the "OEM" specs for lobe lift on the parts description for a replacement camshaft. According to there specs OEM lobe lift is .239" on intake and exhaust. I am measuring from .228" to .236" on mine.

So if I am understanding this right, and OEM intake lobe height should be from 1.5205" to 1.5244"; or on average about 1.5224" and the minimum lobe height being 1.5063" (according to FSM).
Thus the difference in height being .0161"

Therefore if the lobe LIFT of an OEM spec'd cam is .239" and the lobe lift of my intake lobe is .228", then my cam is .011" shorter than OEM cam lobe lift.

One in the same. Lobe height is the difference from the base to the tip............which is also lift (as measured from the lifter or the push-rod during engine rotation). Just remember that it takes 2 crankshaft revolutions to complete 1 camshaft revolution. Tim

I just zero the dial gauge and turn the crank over by hand until the dial hand stops increasing and goes back to zero and record where it peaked at.

Edit: I just measured them all. Out of all 8 lobes all but one is within tolerance. There are a few close to the minimum height allowance and one is .0002" away from it. But would that be enough to be causing my issue?

No. With hydraulic lifters there's quite a bit of leeway. The cam lobes would need to be much worse to make that kind of noise. Camshafts are case hardened, meaning the hardening only penetrates down into the metal a few thousandths of an inch. Typically it takes years and many hundred thousand miles to wear through the hardened surface, but once that happens, the lobe(s) will go flat amazingly fast (like in ~ 50 miles). Since yours all measure so close, I would think the cam is fine.

About the only thing left is to check (if you haven't already) is play/looseness between the rockers and the push rods. In that video it sure sounds like valve train noise........but hard to zero in on it from a video. Tim

Huh, well if the lifters, pushrods and rocker arms are all brand new then where would the play be coming from? Also, thanks Tim for all your expertise and input. I really appreciate it and would have probably thrown the towel in awhile ago without it.

Sorry to hear about all your troubles Terrance, having been down similar roads, I remember all too well how frustrating it can be.

As I read thru your story it sounds like you have replaced everything at least once and sometimes twice and nothing has effected the sound.
Given all the issues you've had with the rebuild, it does sound as though they may have taken a short cut here and there (AM h/g...)

I did note that you said the engine shop replaced the camshaft already?
Is there any possibility they used either the wrong cam (3Y vs 4Y, don't know if theres a difference or not) or possibly put in a regrind??
Back in my speed shop days, there weren't a lot of performance cams available and those that were available were incredibly spendy.
We often had cams reground and while some worked out sweet as pie others had excessive valve noise.

Given how far you've gone on this, it might be worth finding out what they put in, even if just to eliminate one more possibility.
BB

4y and 3y cams share the same part number so I'm not worried about that. But being that the clearance is within tolerance I assume that it's not the problem? I had this thing rebuilt over a year ago so I'm not sure they even would know. On my receipt it just shows "cam" and the price for they charged me for it (around $200). I guess it wouldn't hurt to give them a call.

Is it normal for the CEL to not come on when you turn the key to start?

I'm trying to check for codes since the van won't start now but I can't even get the light to come on with just the key in the ignition. Nothing changes when I jump the check engine connector.

None of the fuses are blown, battery is full and all the grounds are good.

Sounds like you may have a bad bulb or possibly a computer or wiring issue. The CEL should illuminate with the rest of the warning lights when the key is in the "run" position with the engine NOT running.

Bulb is fine, I guess I'll have to pull the ecu and see if it's getting power and whatnot.

Quote:

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Originally Posted by timsrv

Hello Bala. 1st thing we need to do is make sure you are jumping the correct connector. On your van the "Check Engine Connector" is among a group of 3 dead-end terminals right behind the air flow meter. It's the medium sized one and the only one with 2 wires going to it. One wire is brown and the other is gray with a black stripe. Here are some pictures of the "check engine connector":

http://i8.photobucket.com/albums/a23...v/IMG_0104.jpg

http://i8.photobucket.com/albums/a23...v/IMG_0106.jpg

http://i8.photobucket.com/albums/a23...v/IMG_0107.jpg


If nothing happens when you jump those wires (no check engine light and no change in idle), and the connector is in good shape, then this indicates a problem with the ECU or the Check Engine circuit somewhere in the harness. You could try swapping ECUs (if you happen to have an extra one laying around) or you could test the harness with an ohm meter at the ECU connectors. Since you probably don't have an extra ECU, then you'll need to gain access to your ECU (mounted in the D/S pillar behind where your seat belt retracts to), and unplug the harness. Now you can test for continuity between positions "T" and "E1" in the harness. Here is a map of the ECU connections:

http://i8.photobucket.com/albums/a23...v/IMG_0116.jpg


http://i8.photobucket.com/albums/a23...v/IMG_0118.jpg

With the "check engine connector" empty there should be no continuity. With it jumped there should be. If the harness tests okay, then the problem is in your ECU. If you are not getting continuity between these 2 pins with the jumper in, then your problem is in the harness. If this is the case, your choice would be to find the fault and repair the harness or you could cut some insulation off these two wires at the ECU and touch them together. Touching them together at the ECU will have the same effect as jumping the engine connector, but would be somewhat of a "hack" thing to do. If you go this route, just be sure to tape them up when you're done.

If none of this works, tell me what you did, what you found, and we'll move on to a couple other things you can try. Tim

PS: When you changed the TPS did you adjust it per specs using an ohm meter?

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And here's a link to a thread where a member repairs his own ECU:

http://www.toyotavantech.com/forum/s...k-engine-light

Amazing, thank you.

Pulled ecu and check for continuity at those pins and it is getting continuity when the jumper is in the check engine connector. So I guess it's an ecu issue? I cracked open the ecu and there's no visible issues, the board actually looked really clean. No blown caps, corrosion, burn marks or loose contacts. I guess one evening I'll sit down and check every component. Not much else I can do at this point..


That post is really informative Tim, but unfortunately the 3y ecu looks nothing like the 4y:



http://i.imgur.com/4he3jhu.jpg

Anyone know anything about ceramic capacitors? I have 2 that look bad but I can't figure out what kind they are besides 1000pf capacitors. One has a B (or an 8) about the 102 and the other has a 6 above the 102. Searching around online hasn't turned up anything.


https://i.imgur.com/I14pYt6.jpg

Well, turns out the ECU had nothing to do with the starting issue. After going through the wiring and double checking fuses and relays the damn thing just worked all of the sudden. So something got knocked loose and it fired right up. Still sounded terrible though. So it dawned on my that maybe the exhaust manifold had gotten warped over time so once again I pulled everything apart and lo and behold it was warped pretty bad. Got it ground flat and put everything back together and of course little to no change. This van still runs like roflroflroflrofl and sounds like a tractor. I made a small video of it today idling and revving. When you give it gas the engine shakes and sounds terrible. I have no idea why this thing runs so poorly, why it sounds like this and what to even check next. I made a list of what has been done to date:

Engine overhaul,
rebuild cylinder head,
new pushrods
new lifters

Water in coolant...

new cylinder head, rockers, rocker arm shaft,
new spark plugs
machined exhaust manifold


https://youtu.be/rZICqX3rzlg

Still sounds like excessive valve lash to me.......perhaps accompanied by a miss. A miss can be caused by low compression in a cylinder, no fuel in a cylinder, or no spark in a cylinder. I'd take care of the racket 1st. If indeed it is valve lash, then fixing this may even take care of the miss. No fuel to a cylinder could be an injector and no spark to a cylinder could be a defective plug wire and/or damaged plug. Did you ever measure lift and check for excessive lash? Have you checked compression? Tim

Edit: just wanted to say it's impossible to tell from a video........Everything I said is just a hunch/best guess. It's up to you to do the actual investigation and/or hire somebody. Tim

Quote:

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Originally Posted by timsrv

Still sounds like excessive valve lash to me.......perhaps accompanied by a miss. A miss can be caused by low compression in a cylinder, no fuel in a cylinder, or no spark in a cylinder. I'd take care of the racket 1st. If indeed it is valve lash, then fixing this may even take care of the miss. No fuel to a cylinder could be an injector and no spark to a cylinder could be a defective plug wire and/or damaged plug. Did you ever measure lift and check for excessive lash? Have you checked compression? Tim

Edit: just wanted to say it's impossible to tell from a video........Everything I said is just a hunch/best guess. It's up to you to do the actual investigation and/or hire somebody. Tim

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I have looked everywhere in the FSM on valve train clearances and I can seem to find anything other than oil clearances. Beyond that its just how to slap it all back together. How would I go about check lash if I'm not sure what I am check for?

As for compression, I haven't checked it since I got it running again. When the rain lets up I'll check it.

I'm sure I made at least one "long winded" post previously in this thread explaining how to measure/adjust valve geometry. Not sure how it could be off, but something is making a racket. No way to know for sure until you measure for lash (excess play) at each rocker/push-rod. If it is off, then the simplest solution would be to get custom push-rods (pretty sure I gave a link or 2 previously). FYI, this is not a common issue, but I've run into it before. It's usually caused by a machinist who wasn't properly trained and/or wasn't aware these valves are non-adjustable. If it's an aftermarket head, it's also possible there's dimensional errors in the height of the rocker arm mount bosses. Maybe the wrong lifters??? (who knows). Whatever the reason, if it's loose valves, then you'll need to have some custom work done. Over my career as a mechanic, I've only ran into this once. It was on a Ford 460 (also hydraulic lifers with non-adjustable rockers). In that case I was able to shim each rocker stud to obtain correct geometry.

That engine had individual rockers/fulcrums though. Since the 4y uses a common rocker shaft, the only way to adjust would be with custom length push rods. With some careful measurements, math, and some custom push-rods it could be dialed in. Of course that's assuming it's a valve lash issue causing all that racket. Tim

Terrance - Everything Tim says is spot on (no surprises there)

All I can add is my own experiences, I once had a customer with a 22R that had replaced his own VC gasket.
It kept leaking and he kept tightening. Brought it in with a sound just like yours.
Replace the A/M gasket and torqued to spec and all noises went away (valve train had been hitting the cover due to the over torqued, cork gasket)

Have you gone over it with a stethoscope? I would want to nail down just where the sound is emanating from, before doing anymore explorative surgery.

Way, way back, we had a customer that used a TV for drug store deliveries. That van led the hardest life of all.
At one point it bent a pushrod (don't remember the specifics of how or why) but as it was a weekend repair and had no parts available, we ended up swapping in a SBC pushrod, had to cut it down a wee bit and brazed the ball back on.
I never expected it to work for long but they put another 100K on it with no issue.
Pretty hack stuff and not something I would recommend, more just a food for thought type of thing.

Given how loud it is you should be able to at least track where the noise is coming from, that will be half the battle.

Quote:

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Originally Posted by timsrv

I'm sure I made at least one "long winded" post previously in this thread explaining how to measure/adjust valve geometry. Not sure how it could be off, but something is making a racket. No way to know for sure until you measure for lash (excess play) at each rocker/push-rod. If it is off, then the simplest solution would be to get custom push-rods (pretty sure I gave a link or 2 previously). FYI, this is not a common issue, but I've run into it before. It's usually caused by a machinist who wasn't properly trained and/or wasn't aware these valves are non-adjustable. If it's an aftermarket head, it's also possible there's dimensional errors in the height of the rocker arm mount bosses. Maybe the wrong lifters??? (who knows). Whatever the reason, if it's loose valves, then you'll need to have some custom work done. Over my career as a mechanic, I've only ran into this once. It was on a Ford 460 (also hydraulic lifers with non-adjustable rockers). In that case I was able to shim each rocker stud to obtain correct geometry.

That engine had individual rockers/fulcrums though. Since the 4y uses a common rocker shaft, the only way to adjust would be with custom length push rods. With some careful measurements, math, and some custom push-rods it could be dialed in. Of course that's assuming it's a valve lash issue causing all that racket. Tim

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Tim, as always thank you for your advice. I am still not sure how I can check for lash on this thing other than seeing if a feeler gauge fits under the valve spring side of the rocker arm (since the pushrod sets inside of a recess in the rocker arm). You said these things are zero lash, which makes since, therefor there should be no clearance between the rocker arm and either the pushrod or valve spring? The lifters have measured and replaced the lifters (I actually have 2 different sets from different manufactures) and it made not difference.

Quote:

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Originally Posted by Burntboot

Terrance - Everything Tim says is spot on (no surprises there)

All I can add is my own experiences, I once had a customer with a 22R that had replaced his own VC gasket.
It kept leaking and he kept tightening. Brought it in with a sound just like yours.
Replace the A/M gasket and torqued to spec and all noises went away (valve train had been hitting the cover due to the over torqued, cork gasket)

Have you gone over it with a stethoscope? I would want to nail down just where the sound is emanating from, before doing anymore explorative surgery.

Way, way back, we had a customer that used a TV for drug store deliveries. That van led the hardest life of all.
At one point it bent a pushrod (don't remember the specifics of how or why) but as it was a weekend repair and had no parts available, we ended up swapping in a SBC pushrod, had to cut it down a wee bit and brazed the ball back on.
I never expected it to work for long but they put another 100K on it with no issue.
Pretty hack stuff and not something I would recommend, more just a food for thought type of thing.

Given how loud it is you should be able to at least track where the noise is coming from, that will be half the battle.

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The valve cover gasket caused an issue? I'm guessing something to do with crank case pressure? I can take my oil fill cap off and it doesn't make a bit of difference to the way my engine runs. I don't have a stethoscope but maybe I should invest in one..

Quote:

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Originally Posted by terrence

Tim, as always thank you for your advice. I am still not sure how I can check for lash on this thing other than seeing if a feeler gauge fits under the valve spring side of the rocker arm (since the pushrod sets inside of a recess in the rocker arm). You said these things are zero lash, which makes since, therefor there should be no clearance between the rocker arm and either the pushrod or valve spring? The lifters have measured and replaced the lifters (I actually have 2 different sets from different manufactures) and it made not difference.

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If you don't have an adjustable magnetic mount and a dial indicator, you could measure lash between the rocker and the valve. However, this will only work if the rocker shaft (pivot point) is the exact center between the push-rod and valve stem. If it's off-center, it could still work, but you would need to measure how far off-center it is, then use math to determine lash on the push-rod side. If you have a suitable dial indicator and magnetic base, set it up so the business end of the indicator rests on the rocker arm (directly above the push-rod). With the lifter sitting on the base of the cam lobe, grab the rocker and rock it back and forth (hand pressure). The indicator will show how much slop (if any) is on the push-rod side.

Quote:

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Originally Posted by terrence

The valve cover gasket caused an issue? I'm guessing something to do with crank case pressure? I can take my oil fill cap off and it doesn't make a bit of difference to the way my engine runs. I don't have a stethoscope but maybe I should invest in one..

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I've seen what Burntboot was referring to as well. it was almost common on the 22R's with the rigid aluminum valve covers. When DIY/amateur mechanics over torque valve cover nuts it can cause an issue. Since the valve cover studs are also the rocker shaft studs, high torque on the cover can tug on the rocker shaft enough to create valve noise........but nothing like what you're experiencing. I'm not convinced the 4y stamped steel cover could transmit that much force without 1st bending/collapsing. Tim

Well, good new is that all cylinders have the same compression psi. Bad news it's still only 120psi. There was some oil on the #1 spark plug tho.

I pulled the valve cover and if I am understanding you right Tim, I am measuring the push rod when it's as high as it can go (on the cam lobe)? If that's the case then there is no movement in the rocker arm at all. When the cam is at its lowest point, that's a completely different story. I don't know if I should be able to push down on the lifters but the push rod can be moved down 1/4 to 1/2".

120 psi isn't bad, the important thing is they're all the same. Valve lash is measured when the cam lobe is at it's base (and the valve is closed). Your push rods will be their lowest (loosest) when the cam lobes are at their bases. I personally like to rotate the engine to position the particular lobe (for the valve I'm measuring) at it's very base, then repeat X 8 (but that can be a little time consuming and not completely necessary). If you put the engine on TDC, you can measure the lash of 1/2 the valves (the loose ones). Then rotate the crank 360º and measure the other half. Tim

Terrance - Hydraulic lifters shouldn't have any play when the pushrod is at its lowest point of travel.
When you say you can push down the pushrod (1/4-1/2in), is there resistance or is it sloppy?
Neither one is right but slop is excessive play whereas squishy resistance is a bad lifter.

I've only done a couple of lifter replacements and that was a long time ago.
We used to pump them up in a can of oil till hard, prior to installing and I remember them being a b**** to do.
I wouldn't think you'd be able to get enough purchase to compress a good lifter, when its installed and pumped up.

To expand on what BB said, once lifters are "pumped up" (interior filled with oil), due to the check valve inside they mimic solid lifters (oil has nowhere to go unless more oil is being pumped in). On engines with non-adjustable valves (like ours), it's not a good idea to manually "pump them up" before engine assembly. Other than external lubrication, I always installed them dry, as they will find the correct adjustment spot faster with less stress on the valve train. If you manually pump them up before installation, the valves can be over extended (at least initially) and that can make them fail to seal and/or can even result in a burnt/warped valve. In some extreme situations it's conceivable they could even contact pistons (causing extreme damage). I don't think that's what's going on here, I just felt the need to explain why they should not be pre-pumped.

If you position the engine so that any given lifter is on the base of it's cam lobe, there should be no lash (play) between the rocker arm and the valve stem. If there's enough lash to put a feeler gauge between the rocker and the valve, and the lifter is fully extended, then there's a problem. If you find excessive lash, use a flashlight to look down at the lifter while you work the rocker by hand to make sure the play is not internal to that lifter. If the push-rod is loose, and the inside of the lifter is fully extended, then you will need custom push-rods. Tim