Anyone know how to disassemble 4.0 hydraulic roller lifters? I have done this on sb chevy lifters, mine look squeezed together.

They appear very high quality, no looseness, wear, etc.

ken

 

Ken, if they look good, don't worry about cleaning them. Just do what 96_4wr says, soak them in motor oil and leave them there until assembly.

If you want to clean them, I seem to remember there is a snap ring on top.

 

They seem very "solid" you can't compress them with strong hand pressure at all. I think the soak is gonna be fine. seen a few failed lifters and they just squeeze with finger pressure.

It is interesting, the part that is leaking water, the front timing case, does not even exist on a chevy v-8, at least it doesn't have water in it in the chev. I really am annoyed by unnecessary complication. I always thought the simple chev water pump mount and the dry timing cover was elegantly simple.

Ken

 

Bump this foward to the year 2012!!

I have the same question. How are these lifters disassembled? Whatever 96-4wdr replied did not carry across in this abbreviated version. The manual says there is either a hairpin style clip or others say a snap ring. I see neither on my '91 4.0 with hydraulic roller lifters.

 

Everyone was obviously too polite to tell me how stupid I was for not being able to figure out how to disassemble a lifter. In case there are others in the future who need to know as well, I thought this might help.

First, the Chilton manual does not cover the style of lifter in use on a 1991 4.0 engine. It grossly misleads you into trying to find a spring clip. There is none. Instead, a plastic(?) cup at the very top serves both as a push rod guide when reassembling the valve train components and as a keeper for the lifter assembly.

As the very bottom of the plastic cup are four small slots. Using a fine pick carefully pry upwards in succession along the base of the cup until it is forced off.

Wrap the top half of the lifter in a rag and apply 30-40 psi air pressure to the oil passage hole on the outside of the lifter body halfway down. You can see it in the following picture. The top plunger cup will shoot out easily. The lower cup will revolve aroung in the bore but will not come out easily. I found using a plastic/rubber plug the same diameter as the cup will seal off the oil passage hole in the bottom of the cup and permit you to use air pressure as above. Hold the plug against the cup with a fingertip while applying air pressure. The lower plunger will come partially out then stick. Appy to PB Blaster, push plunger back in the bore and repeat this 15-20 times until the lower plunger pops out.



These are the main components in the order they are assembled. Note the little "tip" on the backside of the lower plunger. That is a retainer cage that hold a very small ball bearing check valve and an even smaller check valve return spring.
This is why you DO NOT want to poke about in the lower plunger cup with a pick. You can dislodge the retainer and lose the ball bearing and spring without even realizing they are there when the lower plunger is finally removed. There is also a spring that will be left behind in lifter bore that simply slides out.

The white cap shown is what I used as a seal for the lower plunger cup. It is just a plastic cap made to fit over a 1/4" peg board hook. Nothing fancy but it worked.



Here is an enlarged view to show the check valve. The retainer is a simple snap/press fit and the ball bearing and tiny return spring. Below is a view of all the componets layed out in their order of assembly.



Words of caution: Mark all lifters to return them to their original engine bores. Do only one lifter at time. The internal parts are somehow mated to each individual lifter. You should not mix and match components.

After assembling, you should now be able to observe plunger action when the center is pressed down with an emply plastic pen or artist paintbrush handle. Coat the lifter with engine oil and return to original bore.

 

Just curious, why did you have to go through this exercise? Noisy lifters? Boring weekend?

 

I'm not good with little ***** and springs anymore, bad eyesight and bad legs for crawling around on the floor with a magnifier and strong magnet.

 

My recently rebuilt engine blew a head gasket. When running it up on the car trailer there was a new, noticeable engine related clicking sound. It seemed topside and about the only thing up there that would make such a sound would be lifters. The old ones appeared to be in good shape and I reused them on the rebuild. (I was ignorant about the actual hydraulic functioning and the machine shop said roller lifters are good forever, so back in they went.) When I took a closer look this time, I found every one of them to be 'stuck' - with no hydraulic action whatsoever. Strangely, I never had any lifter noise prior to this time.

Because I had no noise previously, I am still not certain the problem is not a connecting rod bearing or wrist pin failure from possible hydrolock. Nothing about this engine failure makes any sense and my first theory (bent push rod) was disproven.

 

I have a kind of ticking sound in my engine as well. I noticed a couple of times starting the engine after a long period of non-use that it would make a loud clatter for the first 15 seconds after first starting, quieting down to the ticking noise. The ticking is not very loud, and has not gotten worse over the years. But I am concerned that sometimes it seems all the oil drains out of the engine from sitting around for too long. If I had to let it sit for an extended time again, before starting, I would probably try to run the starter for a few seconds by shorting the relay while the key is off to try to prime the oil.