Valve Lifters

[caeruleus]

Folks -

A couple years ago, I bought a back-up A4 that had been mostly rebuilt from the journals up and is clean and shiny, with a bunch of old parts that were with the engine. The engine sat in my shop, unheated for about a year or so, covered with a plastic tarp, with plenty of airspace around it. I just took it out this week to start putting it all together again, and hopefully put it in my boat before she goes in the water in a month or two. The block is assembled and attached to the oil pan, but the head is still off.

All seems to be functioning properly, and everything turns when I put the crank on it, but the valve lifters don't want to spring back down properly and need a little persuasion. Ive been hosing them down with PB blaster every few hours for a couple of days and I'm making some headway, but most of them are still really sticky and one of them is still stuck.

Is there anything else I should be doing to un-gum them? Pour vinegar on 'em? Seafoam? Hit 'em with a big hammer?

Thanks for any thoughts,
Chris

Ericson 29
Fair Haven, NY

[lat 64]

I am understanding you have stuck valves in a "new" longblock?

I would say one of two issues:
1. Rust in the valve guides
2. springs are sacked

remedy for either of my ideas:
disassemble and check.

[Sony2000]

If the lifters are not rusted up, then they may have experienced a lack of oil when running causing them to deform. That is, become wider at the base than the top. I had to remove two with a vice grip on each, moving the grip back and forth and raising the lifter at the same time.
This group likes using 50% acetone and 50% Auto Transmission Fluid to release parts.
Also a little propane torch on the lifter, if you dare.

[caeruleus]

Marvel?

I'm trying to avoid tearing the block apart until I've tried everything else. The lifters (from what i can see of them), are shiny and perfect. I'm also thinking about plugging the 4 holes in the bottom of the gallery, replacing the cover, and filling the gallery with Marvel and just letting 'em sit for a few days and see if they free up. Is there anywhere I can see an exploded view of the valve lifter, valve and cam assemblies, to get a an idea of what I'm looking at?

[caeruleus]

Lat, the valves are a little sticky but they're snapping down mostly. That problem should clear itself up once the engine starts and heats and I get some engine cleaner working through the system. The problem is in the lifters themselves.

Sony, I'll try your acetone and tranny fluid idea. The tappets *could* be rusted, but I'm thinking more and more that it's gotta be some kind of gummy issue. The engine never ran (and was never completely assembled) since being rebored. So maybe old oil residue from oil they used when sliding the tappets into the guide? I can't imagine that when they put the tappets in they didn't check to see if they were deformed. There's no seal in the tappet guide to get dried out and sticky is there? It's just the tappet directly in its hole in the block? Is there an exploded diagram I can look at of the way the valve tappets, springs and valves are assembled?

Crazy question: If I removed the valves and springs above them, is it possible to lift the tappets out from above into the gallery? or is there some kind of flange holding them in at the bottom by the camshaft?

[lat 64]

I think you are on it. If they are not too rusty, then you are correct in the approach to lube them up and wiggle them back into action.

They are not flanged, but they have to come out the bottom after the cam is out(somebody correct me if i don't remember right). They are just too long to come out through the top of the lifter gallery.

lifters in general are some of the simplest in concept, yet most precision parts of an engine. A little rust or goo can stick them up easy. storage under a tarp outside is never the best. Glad you could get to this before it went too far.

[Sony2000]

No,the lifters remove from the top.
Remove the adjuster, spring, and valve. A 1/2" spanner fits on the top of the lifter to wiggle it.
You can force the lifter down with overnight pressure. Then raise it with the cam.
The bottom of the lifter is the fatest, so lower it.

An off-the-wall idea is to spray it with nitrogen, that will shrink it.

While you are there Caerules, could you develop a technique to clean out the channel of oil that feeds the lifters? I believe that just a little lower, there are 3, 1/8npt tapped holes leading to the oil channel. The ones used for the OPSS, and oil pressure sensor, plus one in the middle.

[Ball Racing]

Never heard of anyone removing them from the top.
I would never remove the adjuster from the tappet.
The fit is a locking fit, so the more the adjuster is turned the more the threads are deformed, and will be losing the ability to keep your adjustment.

[Sony2000]

My engine was in a crate, in the middle of a shipyard the summer of 2011. I believe the only way to remove the lifter from the top, is to remove the adjuster. After removing 2 (each at the extreme ends of the gallery) I resurfaced both before replacing them.
Shortly afterwards, I entertained the staff, with the sounds of an Atomic 4 running inside it's crate!
That would never have happened without this forum.
Can there be more than one type of lifter? I don't think so.

[Ball Racing]

Can there be more than one type of lifter? I don't think so.

?????? Not sure I follow..
There were 2 different size,shape heads for the adjuster. Both of my motors are from the 70's and one has a large thin just bolt looking head. The other has a smaller deep looking head. Two different wrench sizes.

[Sony2000]

Since I did it only once so I'm not too clear on the adjuster.
It threaded inside the lifter and had a nut to keep the adjustment. There was a crown of 1/8" on top of the lifter where I slid a 7/16' or 1/2" spanner on it to work in some play and oil.
To pry the lifter up, I used a vice grip with a flat jaw on this crown. I wiggled it, and pryed the vice grip up with a large screw driver, until the lifter was free.

Now the engine is in the boat and as a Spring project, I hope to clean out the oil delivery channels to the lifter and bearings I guess, so the problem doesn't happen again.

[caeruleus]

Not quite following you here, Sony -

"While you are there Caerules, could you develop a technique to clean out the channel of oil that feeds the lifters? I believe that just a little lower, there are 3, 1/8npt tapped holes leading to the oil channel. The ones used for the OPSS, and oil pressure sensor, plus one in the middle."

While I'm where? Where is the oil channel? A little lower on what? In the valve gallery or underneath by the journals? The valves seem lubed by those 3/4 inch holes down into the crankcase... no?

And if they're fatter on the bottom, how can they come out through the top?

[lat 64]

Now I'm getting it. I removed my lifters out through the bottom because I was doing a complete teardown. It is easier. Good to know one can unscrew the adjuster and remove the lifter from the top. that would be good for repairs on the engine in-situ.

I agree that doing so might shorten the life of the locking screw threads, but I have no experience that it will on an A-4. But, I have seen a few worn out locking threads on auto engines, so it is a concern here.

I hope the homebrew penetrant and time will be the solution for you.

[lat 64]

Not quite following you here, Sony -

"While you are there Caerules, could you develop a technique to clean out the channel of oil that feeds the lifters? I believe that just a little lower, there are 3, 1/8npt tapped holes leading to the oil channel. The ones used for the OPSS, and oil pressure sensor, plus one in the middle."

While I'm where? Where is the oil channel? A little lower on what? In the valve gallery or underneath by the journals? The valves seem lubed by those 3/4 inch holes down into the crankcase... no?

And if they're fatter on the bottom, how can they come out through the top?

@ C. The second photo I posted shows my fingers on the lifter pulling it out the bottom. You can see the unworn part of the lifter. It is yellowish with goo. This makes it just a bit "fatter" and it won't slide up through the lifter bore easily, So it sticks. Sometimes an engine lifter will also get a little lip from running on the cam and it sticks if you push them up into the bore. that is not true in all engines, but I can't remember the specific geometry of the A-4.

Hope that helps. Gotta go to Easter brunch with the in-laws now. I'll check back later.

Russ

[Sony2000]

....a little lower on the block below the gallery..... In the first picture, one of the tapped holes is front and center with a plug in it.

If the lifter ever experienced a lack of oil, the cam pushing from below, the hollowed out lifter tends to be compress, and it bulges at the bottom.

Or, there is an accumulation of sludge with time.
Seafoam has a decarbonizing spray sold as a penetrating oil.
Good results against carbon build up is achieved with brake cleaning spray.
But if it is stuck tight, constant pressure from a pry bar overnight may do the trick. Just make sure the other valve is opening.

Put the propane torch to the journal. The heat can weaken the seal.