How To: Remove the Camshaft Rocker Arms

Mattx2

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Ok guys, let's get started.

First - Un-screw the phillips head on the out side of the rocker top.

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After thats out of the way, now you have to punch out the guides for the alignment rods to access the rocker pivot slug.

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For this, i used an 8mm socket. It was the perfect size to slide those babies out.

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Part 2

Remember to Bag-n-Tag those bad boys.

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Also, only take apart one at a time. That way you can keep track of which part goes with which side. You don't want to mix up parts.

Ok ,,, moving on

Next to come out is the rocker arm pivot slug.

For this task, it calls for a 6mm screw. I just used one of the long allen head bolts from the clutch cover. Worked like a charm.

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I used a slide puller to slip out the slugs.
Something like this (Not mine)

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After the slug is pulled, the rocker arm should fall right out of the head.

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*Repeat 3 more times* :)

Then your left with an open rocker top. Time for new seals and a good cleaning through the oil ports.

Thats it! Short and sweet.
 
How important is it that slugs go to the exact location from which they came? They all seem the same to me and likely machined to the same spec.
 
I was wondering the same thing? I haven't assembled my engine yet but was wondering about the hole in the middle of the slug. Does the hole have to be lined up with anything?
Or are you saying that they should go back in the same location? Sorry to Hijack your thread.
I'm sure someone will chime in hear...
 
I was wondering the same thing? I haven't assembled my engine yet but was wondering about the hole in the middle of the slug. Does the hole have to be lined up with anything?
Or are you saying that they should go back in the same location? Sorry to Hijack your thread.
I'm sure someone will chime in hear...

The rocker shaft has an annular space so that oil can flow through the rocker arm and spray onto the rocker arm and camshaft lobe. My picture has some red wires showing the oil path.
 

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They may have been made the same, but after 30 some years are they still the same?
Put the same shaft in the same rocker in the same position. Oh, one more thing. Put them in with the threaded hole out. You might need to pull them again.
Leo
 
Sorry before hand if this is a stupid question but how do you know if the hole in the slug is lined up with the hole in the rocker arm once its in the rocker top? I'm guessing the + on the slug head.
I only ask because I haven't got to this stage yet.
 
Sorry before hand if this is a stupid question but how do you know if the hole in the slug is lined up with the hole in the rocker arm once its in the rocker top? I'm guessing the + on the slug head.
I only ask because I haven't got to this stage yet.

There is nothing to line up. The annular groove on the rocker shaft can supply oil regardless of the shaft/rocker arm rotary position.
 
Part 2

Remember to Bag-n-Tag those bad boys.

View attachment 7910

Also, only take apart one at a time. That way you can keep track of which part goes with which side. You don't want to mix up parts.

Ok ,,, moving on

Next to come out is the rocker arm pivot slug.

For this task, it calls for a 6mm screw. I just used one of the long allen head bolts from the clutch cover. Worked like a charm.

View attachment 7908

I used a slide puller to slip out the slugs.
Something like this (Not mine)

View attachment 7913

View attachment 7909

View attachment 7911

After the slug is pulled, the rocker arm should fall right out of the head.

View attachment 7912

*Repeat 3 more times* :)

Then your left with an open rocker top. Time for new seals and a good cleaning through the oil ports.

Thats it! Short and sweet.

Actually there's no need for a slide puller, to remove the rocker spindles. Just use a few spare washers, to act as a shoulder, which a 6 mm bolt of the correct length, can turn against. This is clearly shown on page 43 of the Haynes manual.
 
There is sometimes a bit of a lip, with this it's easy and quick.
Grind a bolt head down to fit inside the threaded collar on the puller. I may have drilled the collar to fit the bolt shank also.

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Another thing might be to get four long 6 mm bolts and leave them in the rocker arm pivots untill you reinstall the pivots. That way you can't install them wrong.
Leo
 
I took the head in and had a valve job done. I have the rocker cover, and have got the o-rings for the guides for the alignment rods but am afraid of screwing them up. If I don't change those is that going to course a leak or sealing issue?
 
If you don't take anything apart, you probably won't get any leaks. If you take things apart new seals, gaskets and o-rings are cheap insurance against leaks.
Leo
 
Actually what is more important than getting the "slugs" (actually those are called rocker shafts) back in the same holes is to get the rockers back onto the same lobes of the cam after checking to be sure that there has been no unusual wear or unusual contact between the rocker arm and the lobes.

Also, I am not seeing how you could install the shafts wrong if you merely LOOK at them to see that you are putting the end into the shaft hole that does NOT have the threaded hole in it.

It may not really be a hot tip or a "trick", but normally one looks at things when taking them apart, paying attention to the details (or take a BUNCH of pictures with you digital camera) to ensure that you put them back together correctly.

I also recommend, any time the top end is apart to the extent that you can see it, you examine the front cam chain guide to see if it is all still intact and that the plastic part that contacts the chain has NOT fallen off and down into the crank case. I have seen them in pieces with under 10,000 miles on the engine!! (pic is of guide and plastic pieces from an engine with about 9600 miles on it! It was completely off of the metal guide and down in the bottom of the crank case)

PS..a really easy way to make a tool to quickly and easily extract the rocker shafts is to find a big nut with the correct threads to screw onto your slide hammer, just quickly weld (about 45 seconds with the MIG welder) a long 6mm screw with the correct thread pitch onto the nut and then screw the whole works onto the end of the slide hammer. Voila!: a home made tool that you can use to ease the removal process. (see pic)( I threw mine in the lathe and turned the weld down a little, but that is NOT a necessity!)
 

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Actually what is more important than getting the "slugs" (actually those are called rocker shafts) back in the same holes is to get the rockers back onto the same lobes of the cam after checking to be sure that there has been no unusual wear or unusual contact between the rocker arm and the lobes.

Also, I am not seeing how you could install the shafts wrong if you merely LOOK at them to see that you are putting the end into the shaft hole that does NOT have the threaded hole in it.

It may not really be a hot tip or a "trick", but normally one looks at things when taking them apart, paying attention to the details (or take a BUNCH of pictures with you digital camera) to ensure that you put them back together correctly.

I also recommend, any time the top end is apart to the extent that you can see it, you examine the front cam chain guide to see if it is all still intact and that the plastic part that contacts the chain has NOT fallen off and down into the crank case. I have seen them in pieces with under 10,000 miles on the engine!! (pic is of guide and plastic pieces from an engine with about 9600 miles on it! It was completely off of the metal guide and down in the bottom of the crank case)

PS..a really easy way to make a tool to quickly and easily extract the rocker shafts is to find a big nut with the correct threads to screw onto your slide hammer, just quickly weld a long 6mm X 1 screw onto the nut and then screw the whole works onto the end of the slide hammer. Voila!: a home made tool that you can use to ease the removal process. (see pic)

All your ideas are good ones. I just want to point out a couple of things, to lads doing this for the first time.

First, you don't need to buy a slide hammer. A bolt and some washers will easily withdraw the rocker shafts.

Secondly, you don't need to do any welding.
 
All your ideas are good ones. I just want to point out a couple of things, to lads doing this for the first time.

First, you don't need to buy a slide hammer. A bolt and some washers will easily withdraw the rocker shafts.

Secondly, you don't need to do any welding.


All true, but getting the shafts out with a screw (or bolt), and washers is kind of a long, fiddly process that can be done in about 1 minute if you make up a tool. And, the "retiredgentleman" is correct when he says you don't have to buy a slide hammer...you can easily make one! (and they have MANY uses around the shop!) If you can't weld, you should learn how to....it is AMAZING the things you can then fix or make!! :wink2:

PS...I am a self admitted tool freak :yikes: ( I am NOT attending tool freaks anonymous meetings!!) and prefer to make my own "special tools" as it is WAAYY cheaper and WAAYY quicker than buying them!! I have a whole drawer full of them for various applications and use them a lot to make myriad tasks easier!

Oh, yeah...I, too am a "retired gentleman", (as in An Officer and a Gentleman.....get it? ) but since I never was and still wouldn't be described by a lot of my friends as a GENTLEMAN, it took an act of Congress to declare me a "Gentleman"!
 
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I've got a good question for the pros about rocker arm shafts:

how much play side to side is normal? should it have any wiggle at all?..

during my last tune-up i recognized that there is greater lateral movement at both exhaust rocker shafts than on intake side. I haven't torn it down yet, it runs great, a little rattly up top but loads of pull and idles ok.

If i suspected that my rocker arm/shaft fit is beyond tolerance can i swap the shafts alone from another lesser used top-cap and reuse rocker arms to maintain the relationship with the cam.. Do the rocker shafts wear typically? or just the rockers? anyone have much experience with this?

can i swap both shafts and rockers and continue to use the old cam? is this a bad idea? or should one source new cam, rockers, and shafts to ensure proper alignment during "break-in"?

thanks in advance
 
If you are really lucky, the rattles could be just that the clearances between the valves and rocker arms are a little on the loose side, BUT....I am assuming that you do NOT mean the shafts move "side to side", but that they actually don't have the correct fit between themselves and either the holes machined into the head cover and/or the rocker arms themselves, right? "Side to side" movement should be prevented by the ends of the holes machined into the rocker cover going one way and by the tubular inserts that let the cylinder studs pass through and are between the shafts and the rocker plugs going the other way.

The cure for either of those tolerances being out of spec would be to first closely inspect and measure all of the parts concerned. Only then will you be able to decide which parts are worn out of spec, but those rocker arms AND, ESPECIALLY the rocker shafts are pretty hard and resist wear quite well if there has always been an adequate supply of oil there. (there has been, right? If maybe NOT, you should also check out WHY NOT and then check out the rest of the engine to see it anything else has been damaged due to lack of oiling). In my mind, the first suspect would be that the rocker cover had been either damaged by poor installation techniques OR by wear as the engine operated...I say this because that cover is aluminum and is, therefore, soft.

ANYWAY, once you determine which part(s) are worn out of dimension/specs, then what you have to do is to find some replacements for them. Personally, I wouldn't have any qualms about using a GOOD used cover, BUT ME...I'd be more comfortable replacing both rockers AND shafts if either one of those parts seem to be the culprit, especially as the parts of the rockers that contact the cam CAN wear. One thing I'd look at if using a replacement cover (either new OR used) is to be sure that where machined spots are on it to mate it to parts like the covers at the ends of the cams and the cam bearing areas are correct and match up perfectly to their matching parts (being a paranoid worry wart!) IF the rockers are badly worn where they contact the cam, take a good, CLOSE look at the cam lobes to be sure they have not been damaged, which is quite likely if the rockers are pretty bad. IF you do wind up using the same rockers you took out of the engine, you should try to get them back into the same positions from which they were removed. (you DID mark them as to where they came from, right?!?!?)

The whole point of all this is to be sure that the valve train is all back in spec before you put the engine back together. If it is NOT back in spec, you WILL BE just asking for more trouble!

I hope this helps...if you have other questions, please ask!!
 
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