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PostPosted: Mon Apr 12, 2010 3:21 pm 
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How to replace lash adjusters (lifters)
By kenamond of DSM Tuners.
http://www.dsmtuners.com/forums/article ... fters.html

This tech article describes how to replace/upgrade your 2g DSM 4G63 lash adjusters (commonly called lifters) without removing the cams. The most common reason for removing/installing the lifters in this manner is to fix the infamous DSM "lifter tick". Although I did this successfully on a 2g 4G63, I'd bet it's applicable to 1g motors, too.

I added revised lifters, but you could instead clean the old ones or put in new stock ones, too. This article does not cover cleaning the lash adjusters. I also skip steps for removing/installing the valve cover.

NOTE: I use "lifter" and "lash adjuster" interchangeably. "Lash adjuster" is the correct term, but "lifter" is shorter to type.

This took me about five hours total. I could have gone faster, but I'm not that kinda guy; I mess up less often when I take my time. This included pulling/installing the valve cover with a new gasket, cleaning RTV off the head/VC surfaces, taking pictures, figuring out how to do this, etc. Again, this article will not cover the valve cover removal/installation. Sorry!

Tools/supplies

New lifters (or you can clean the old ones and re-install them)
Jack/jackstand
Tire iron
Spark plug socket
22mm socket/ratchet/extension or 1/2" drive extension/ratchet
~14" prybar
~10" prybar or flathead screwdriver
4" deep cup
~8oz motor oil
Paper clip
A couple clean shop rags (not for wiping your hands)
Several hours of your time and patience (2-5 hours)
Maybe a drop of blood here and there

Introduction

The image below shows a close-up view of what you'll be toiling with under the valve cover. The rocker links the valve and cam lobe. The rocker pivots on the lash adjuster. The cam spins on the roller that is built into the rocker, and this pushes the rocker down, which opens the valve. The lash adjuster is a telescoping pivot point. The excess play is supposed to be automatically compensated for by the automatic extension of the lash adjuster. Also, the lash adjuster, full of oil, resists compression, so if it extends, it's VERY hard to recompress. You're probably doing this because the lash adjuster isn't taking up all of the slack, so the rocker is tapping on the lash adjuster, cam, and valve stem.

Image

Below is a close-up of a rocker. It's upside down so you can see where the valve stem, cam lobe, and lash adjuster make contact. The tip/top of the lash adjuster fits in the pocket, and this "ball joint" sort of design keeps the rocker from moving toward/away from the valve stem. Oil pumps out the top of the lash adjuster to lubricate the joint, and there is a small hole in the "bump" on the rocker (points toward the valve stem end of the rocker) where the oil drains out of that joint. The two ridges on either side of the valve stem contact point on the other end (right side of the picture) keep the rocker from rotating about the lash adjuster (toward either end of the motor). The rocker is held in place strictly by those pockets - it's constrained so that it can't go anywhere. The cap on the lash adjuster keeps that end from moving laterally in any direction, and the two ridges on the other end keep it from moving toward the left or right sides of the car. I'm mentioning all of this, because it helps to know this when reinstalling the rocker.

Image

Because there aren't any bolts holding the rocker in place, you can pop/pry it out of place. With the rocker out, you can then pull the old lash adjuster out of the head to clean/replace.

However, you may not be able to get the rocker out unless the valve is closed. That means the lobe on the cam must not be down on the roller of the rocker. Also, the lobe of the cam must be pointing "up-ish" or you won't be able to pull the lash adjuster all the way out of the head even if you get the rocker out; as you pull the lash adjuster out of the head, it will run into the cam lobe before you get it all the way out.

Obviously, each pair of intake or exhaust valves (two of each per cylinder) are synchronized, but the intake and exhaust valves on one cylinder are timed differently. Furthermore, each cylinder is timed differently, so the valves for one cylinder are going to open/close at different times than other cylinders. The end result is that you have to crank the motor over maybe several times to get at all of the lash adjusters.

Procedure

Pull the engine fuse or the neg. battery cable. Set the parking brake, block the rear wheels, and put the car in neutral. Loosen the front-left wheel lug nuts, get that corner on a jackstand, and pull the wheel off so that you can get at the crank pulley. It's either a 1/2" drive inside or a 22mm socket outside depending on your preference and/or toolbox contents. Always turn the motor clockwise. If you overshoot, and the cam lobe is in the way, keep going clockwise until you get back to where you wanted the cams. Below is a picture of the driver's side wheel well showing where the crank pulley bolt can be accessed. One of the arrows shows what clockwise is ;)

Image

The valvecover is off, spark plugs are out (so you can turn the motor over easily), so you should plug the sparkplug wells and all of the oil return passages (pretty sure there are three: top right, bottom middle, and top left). I used wadded up paper towels. That'll keep unwanted things from dropping into the combustion chamber or oil return passages (and down into the oil pan if you're unlucky).

You should be able to do all lifters in one cylinder at once. Then turn the motor over until the cams for another cylinder are properly oriented. When you start, there will probably be one cylinder that's already good to go, so starting there wouldn't be a bad idea. It might be a good idea to turn the motor over so that cylinders 2 or 3 are where you start, as they are the easiest, and doing one of these first will give you an idea of the technique.

As I just mentioned, I found that the intake and exhaust cams can both be set up-ish enough that you can do all 4 lash adjusters on a cylinder at one time. But it's close. If one cam lobe is hanging over the lash adjuster a bit too much, you might not be able to pull the lifter out all of the way. If you end up in this situation, you can just drop the lifter back down into its socket in the head and crank the motor around (clockwise!) until you can pull it all the way out. If some of the rockers are out, that means the corresponding valve is closed, so you don't have to worry about the piston hitting a valve. But make sure you don't leave the lash adjuster pulled out as far as you could get it before hitting the cam, or you might damage the lifter/cam/head when turning the motor over (cam pushes lifter to the side, lifter is damaged and/or socket in head is damaged).

Removing the Rockers and Lash Adjusters

Get your big prybar and some clean shop rags. Almost all of the rockers on the intake side can be popped by using the exhaust cam as a pivot (prying between exhaust cam lobes). I put a rolled-up rag over the exhaust cam and then hooked the tip of the prybar under the end of the rocker. Then I held another rag over the rocker with one hand while I pryed up on the rocker - pushing down on the prybar - with the other hand. Just pry straight up. When you pry up on the rocker, it compresses the valve and lifts the rocker off of the lash adjuster. Once you get the rocker off of the lash adjuster, there is nothing left to keep the rocker from pulling away from the end of the valve stem (see the close-up picture of the rocker above - there is nothing keeping the back end of the rocker from sliding off the valve stem). So you pry up and eventually - CLACK!! - the rocker slides off the end of the valve, and the valve snaps shut. The rag over the rocker keeps it from going very far. Most of them would be sitting between the lash adjuster and cam lobe, and the rest just fell down next to the valve spring (don't forget to put those rags in the oil return passages!!). Picture of prying is below, but I was also being cameraman, so the left hand with rag keeping rocker from flying out of the engine bay is not shown.

Image

When working on the exhaust-side rockers, you will run into interference between the handle of the prybar and the throttle cable or throttle cable brackets on the fuel rail. Just roll up a big, thick wad of shop rag and put it between the intake cam and the pivot point of the prybar. This raises the fulcrum of the prybar so that the handle of the prybar doesn't hit the throttle cable. Just wad up the rag so that it's thick enough or use two rags...or three.

For the far-left two rockers (intake and exhaust side), space is a bit limited, but just wad up the shop rag over the sparkplug well. I'm not talking about laying an open rag over it. I'm talking about a 4" wide ball of cloth between the prybar and the head. Gouging the aluminum would be bad. Also, if you find that you need to pry against the cam lobe, use the rolled up wad of shop rag so that you don't score the lobe surface.

After the rocker pops off, find it (may have fallen down into the shadows), pull it out, and put it somewhere safe. Below is what is left.

Image

Pull the lash adjuster out. It might stick a bit. I used pliers to get some to budge, but most came loose with my fingers. One got stuck about half way out, but a gentle tap or twenty on the side with the handle of the prybar got it unstuck. If the cam lobe is in the way, drop the lifter back into its socket and crank the motor (clockwise!!) until the lobe is clear.

I was replacing each lash adjuster one at a time, so that's how I'll describe it. I was installing new (revised) lash adjusters. I assume that if you're cleaning and reinstalling your old lifters, you'd pull them all out (keeping track of which lifter came from where) and clean them. But you should be smart enough to figure out how to adapt this tech article to that situation ;).

Priming/draining the Lash Adjusters

Break out the paperclip and unbend it to look like the picture below. You need to prime the lash adjuster with oil and then drain it. There is an internal check valve that will keep it from compressing. If there is much oil at all inside, you cannot compress it. If you can't compress it, you can't get the rocker back in. If you do get it back in and it won't compress all of the way, the valve won't close all the way (bad when the piston hits it). So at this point, you have a lash adjuster and rocker out of the car, and a paperclip like shown below.

Image

If you stick the paperclip into the hole in the tip of the lash adjuster, you can probe around until you find the "magic button" that releases the check valve. It is a small hole deep inside the lash adjuster that's a bit deeper than the main hole. It takes a bit of probing sometimes, but you'll know when you hit it, because you will suddenly be able to compress the lash adjuster. The picture below demonstrates: the top half is uncompressed, the lower is compressed.

Image

Now, you have to get the new lifter lubed up. When you're done and start the motor, it'll tap like Gregory Hines for minutes until oil pressure finally extends the lash adjusters and removes the slop in the rocker/lash/cam/valve assembly. You want oil on the surfaces of the lifter, but it has to be empty enough that you (and the cam) can compress it. I sacrificed one of my kid's cups, put 3" of motor oil in it (deeper than the lash adjuster is tall), then dunked the lifter with the tip up. Hold the magic button down with the paperclip and pump the lash adjuster until it pumps oil and no bubbles. I couldn't get a picture of that without a dedicated cameraman. The picture below and some imagination should give you the idea.

Image

After that, turn the lash adjuster upside down over the cup with the paperclip still pushing the magic button and pump all of the oil out. I did a good 20-30 seconds for each lifter just to make sure it was empty. When you're done, you should be able to compress the lash adjuster completely and without the paperclip. If you can't, get the paperclip in there again and keep draining.

Installing the Lash Adjuster and Rocker

Drop the lash adjuster back into the head. Make sure you can still compress it all the way (until you feel it bottom out). If you can't, I'd pull it back out, grab the paperclip, and drain it some more until it does compress all the way without the paperclip.

Get the big and little prybars and rags within reach. You only need two hands, but you'll need three if you can't reach these. Put the rag where you need it for prying. Rolling the rag up tightly kept it from smashing as much under the force of the prybar, and this helped me out when I had interference issues such as the throttle cable. You'll probably want to do a dry run to figure out where you need the rag/prybar pivot and how thick of a rag-ball you'll need. Put the rag-ball where you want it or close (might want to fall off the cam, so just put it close).

Now, place the rocker back so that the back end is on the end of the valve stem like in the picture below. You'll probably drop some of them a few times.

Image

You can tell if the rocker is too far back or not far enough back just by getting the bump on the rocker lined up with the end of the lash adjuster. The above image is about right, because the bump on the rocker is about as far away from the (intake) camshaft as the tip of the lash adjuster. If you look at the close-up image of the rocker shown way above in this article, you'll see that the ledges on either side of the valve stem contact point will keep the rocker from sliding side-side, but it can slide in-out, so keep that in mind. Hold the rocker in place with the tip of the big prybar (you'll probably need to get the rocker in place with one hand and hold it there with the other so that you can grab the prybar. While holding the rocker in place with the tip of the prybar, get the prybar in place on the rag (you'll need the other hand that was holding the rocker in place to put the rag where you want it). This can be a bit tricky, but just go easy and don't get frustrated when the rocker falls off the tip of the prybar and you have to start over - that will happen sometimes. After you get the prybar in place on the rocker and rag, grab the other prybar or screwdriver with the other hand so that you can use it to compress the lash adjuster. That's why you need all this stuff within arm's reach. If the other prybar/screwdriver is too far away, the rocker might fall off while you reach for it.

Now you're ready to pry the rocker back onto the lash adjuster.

Take a look at the picture below. You need to be doing two things. You first have to compress the lash adjuster with the smaller prybar/screwdriver in one hand. I'm right-handed, so I did this with my left hand. Then you can pry the rocker onto the lash adjuster with the other prybar in the other hand. To compress the lash adjuster, just get the corner of the prybar/screwdriver in the hole so that it doesn't slip and push straight down (the yellow arrow in the picture below - I couldn't take a picture of me doing both, because I am only blessed with two hands and was alone). Then with the other hand, you need to pry the rocker up and toward the lash adjuster (red arrow in picture below). Prying up will compress the valve which gets the lash-adjuster-end of the rocker high enough to clear the compressed lash adjuster. Prying toward the lash adjuster will send the rocker over the lash adjuster.

Image

Prying up and toward the lifter is the key. You have to be careful so that the rocker doesn't fall off the valve stem while you position the prybar (it'll happen to you several times), but using the wadded rag under the prybar helps keep the angle of the flat head of the prybar so that you can pry in the desired direction without the rocker slipping on the prybar tip, and it keeps the prybar from slipping on bare metal. Get it lined up and angled correctly, compress the lash adjuster, pry the rocker. SNAP! If the rocker doesn't end up exactly lined up on the tip of the lash adjuster, you can pry it into place. It'll snap on. Again, having the rag under the prybar lets you turn the prybar to adjust the direction you're prying the rocker. Without the rag, the flat spots on the prybar shaft and the oil on the prybar handle will fight you. It will probably take you a few attempts on some of the rockers, but you'll get others in one try (I probably got more than half of the rockers on in one shot).

Just remember that the key is to pry up and toward the lifter using a rag under the pivot point of the prybar.

The far left rockers looked tricky at first, but I used a smaller prybar to put them on. I had to pry against the head, but I wadded up masses of rag so that I wouldn't dent/bend/scratch any of the aluminum. I pryed against the left end of the head. This worked out great, because that prys up and toward the lash adjuster. Both went on as easy as any of the others.

I started with the far right end of the motor, and those two were the hardest for me. In hindsight, I'm pretty sure that the only reason they were hardest is because they were the first ones I tried, and I didn't know what I was doing yet. That's why I think you should start with the intake cam side of cylinders #2 or #3 - get used to it on the easy ones.

Finishing Up

When you're done with all 16, pull the rags out of the oil return passages and spark plug wells and turn the motor over manually a couple of revolutions (clockwise!!) to make sure all of the lash adjusters are still adequately collapsed. If there was too much oil in one, the valve won't close all the way, and it could hit the crown of the piston. That's why I spent 20 seconds or longer when draining the lash adjusters after priming. Finding out by turning the motor over slowly by hand is better than finding out when you crank the motor over with the starter. I didn't have any problems with any of the lifters.

Put everything back together.

Pull the engine fuse if you haven't already done so and crank the motor over in 10 seconds spurts with a 30 second break in between so you don't burn up the starter. Removing the fuse disables fuel and spark, but the starter will still crank the motor over. This is supposed to prime the lifters, but I'm not sure if it does much. I did four 10-second spurts.

When you start it, it'll tap like Gregory Hines :) for several minutes. I let the motor warm up holding the revs at about 2k to keep the oil pressure kind of high. Then I held it at 3k for a couple of minutes. You should hear one lifter after another shut up. I then took it for a 1-mile drive with a few ticking lifters, but when I got home, no ticking. Wow, what a difference!!

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