m30 head rebuilding 101

E28 technical advice asked and given! Troubleshooting, modifications and more.
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Nebraska_e28
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m30 head rebuilding 101

Post by Nebraska_e28 »

Use new oil spray bar if old unit is even .01% suspect. With new banjos & crush washers obviously.
Also, if not using the iron maiden tool for cam install be sure not to forget to tighten the cam plate bolts. Easy to overlook. :roll:
ARico08
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Re: m30 head rebuilding 101

Post by ARico08 »

I'm actually about to embark on my own head rebuild adventure so I wanted to ask, what is this iron maiden tool you speak of? I tried doing a quick google search and I'm just getting a bunch of Iron Maiden album covers.
SlickDizzy
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Re: m30 head rebuilding 101

Post by SlickDizzy »

ARico08 wrote:I'm actually about to embark on my own head rebuild adventure so I wanted to ask, what is this iron maiden tool you speak of? I tried doing a quick google search and I'm just getting a bunch of Iron Maiden album covers.
There are a few variations but this is basically what they look like.

Image
Mike W.
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Re: m30 head rebuilding 101

Post by Mike W. »

SlickDizzy wrote:
ARico08 wrote:I'm actually about to embark on my own head rebuild adventure so I wanted to ask, what is this iron maiden tool you speak of? I tried doing a quick google search and I'm just getting a bunch of Iron Maiden album covers.
There are a few variations but this is basically what they look like.

Image
That's cheating!!! :evil:
ARico08
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Re: m30 head rebuilding 101

Post by ARico08 »

I see where it got its name from haha. I assume this compresses the valve springs for easy assembly? Is the head rebuild job a pain in the ass without it? I'm still gathering all the parts for my head rebuild and I'm trying to gather as much info as I can before I dive in.
Mike W.
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Re: m30 head rebuilding 101

Post by Mike W. »

It compresses the rockers to allow easy removal of the cam, which then makes dis/reassembly of the head significantly easier. PITA? Medium I'd say. Not really all that bad, depending on how the rocker shafts come out, but care and caution is required not to break things.
Nebraska_e28
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Re: m30 head rebuilding 101

Post by Nebraska_e28 »

Ditto what Mike said on removal of shafts. To ease this, hot tank the head prior to disassembly. You'll thank yourself later.

Rocker shaft removal sequence (without tool)
1. exhaust rear
2. intake rear
3. intake front
4. exhaust front (this one takes advanced Tetris/Jenga skills)

Installation is reverse of sequence.
ARico08
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Re: m30 head rebuilding 101

Post by ARico08 »

Thanks for the info! I'll have to find a place around here that will hot tank the head for me. I've got a valve spring compressor on the way, would it be easier to pull the valves and springs first or leave that for after the rockers have been removed?
Nebraska_e28
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Re: m30 head rebuilding 101

Post by Nebraska_e28 »

ARico08 wrote:Thanks for the info! I'll have to find a place around here that will hot tank the head for me. I've got a valve spring compressor on the way, would it be easier to pull the valves and springs first or leave that for after the rockers have been removed?
Wear eye protection!
compress spring
remove retainer
remove spring
drop valve
repeat 11x
remove shafts/rockers in specified order
Mike W.
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Re: m30 head rebuilding 101

Post by Mike W. »

ARico08 wrote:Thanks for the info! I'll have to find a place around here that will hot tank the head for me. I've got a valve spring compressor on the way, would it be easier to pull the valves and springs first or leave that for after the rockers have been removed?
Degreasing is fine, but not a hot tank. Caustic soda will melt the aluminum. Probably half the time I've done heads nothing has gone to the machine shop so degreasing is Simple Green and a hose in the backyard, sometimes followed with a bit of engine degreaser, the aerosol type that's water soluble. If we ever get a new dishwasher and the old one is still working that might change. :D If I can find a place to put it. :evil:

And I do things a bit different than LJ. Pretty much the first step for me is to drive out the rocker shafts and in pretty much random order. Then I can get to the valve springs etc. Driving them in is pretty much the same, random, just be very careful you get the right one in the right place. No criticism of LJs technique, except maybe that my valve spring compressor won't work with the rockers in place, just an alternative way of doing it.
Shawn D.
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Re: m30 head rebuilding 101

Post by Shawn D. »

Mike W. wrote:
ARico08 wrote:Thanks for the info! I'll have to find a place around here that will hot tank the head for me. I've got a valve spring compressor on the way, would it be easier to pull the valves and springs first or leave that for after the rockers have been removed?
Degreasing is fine, but not a hot tank. Caustic soda will melt the aluminum.
I just had an intake and oil pan hot tanked and they weren't damaged at all. Perhaps they were using a different solution.
Mike W.
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Re: m30 head rebuilding 101

Post by Mike W. »

I haven't had a block hot tanked in a long time, but it's a specific process that uses caustic soda and apparently so good it's very much under fire from the EPA, at least on the disposal end. The shop I use also has a tank with a carburetor cleaner like solution they use on soft metals, which does ok, but not like hot tanking.
ARico08
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Re: m30 head rebuilding 101

Post by ARico08 »

I just got the valve spring compressor yesterday so we will see how that works out for me this weekend. I'll give the simple green method of cleaning a shot as well and see if that helps loosen anything up. I really only plan on reusing the head itself and the rocker shafts so I'm not too worried about everything else.
BuzzBomb
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Re: m30 head rebuilding 101

Post by BuzzBomb »

ARico08 wrote:I just got the valve spring compressor yesterday so we will see how that works out for me this weekend. I'll give the simple green method of cleaning a shot as well and see if that helps loosen anything up. I really only plan on reusing the head itself and the rocker shafts so I'm not too worried about everything else.
You can reuse anything as long as it's reusable.
Shafts: inspect for wear at rockers. Only reuse if you can't feel any ridges with your fingernail, otherwise new rockers will be prematurely wear or have too much axial play.
Either use a slide hammer threaded into the shafts to remove them, or have a long drift only slightly smaller than the shaft to drive them out ( If you mushroom one of the shaft ends with this method, you're fcukd ).
Observe the sequence of the rocker shaft hardware. It needs to go in that specific order and orientation.
Inspect the cam lobes for excessive wear, replace it if there is any question. Don't use new rockers with a cam with obvious wear, don't use old rockers with a new cam.
If you have to use excessive force to get any of the shafts out, your head is probably warped and isn't worth the machine shop labor to fix it. Start with a good core.
As Mike said, the shafts have to be removed before the valves can be removed. Trying to reverse this process is working way too hard.
Rust Bucket
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Re: m30 head rebuilding 101

Post by Rust Bucket »

I'm actively looking for a Iron Maiden tool.Willing to buy.

Anyone interested in a cooperation to produce a couple of these?First thing we need is to locate somebody who got one,to have dimensions.It does'nt look like a complicated
thing to do.I saw a video of a guy using one for the M10,
I was wurprised to see the thing got an arm to compress valve springs.
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