Rocker shaft stuck -- head warped?

#1

Couple questions as a begin rebuilding the head I pulled off a cheap spare long block I’d bought.

  1. I’m mid-rocker shaft removal. All the tension is off the rocker arms, but it’s still taking some serious tapping to get the thing to budge (and it certainly won’t slide out by hand). I’ve got it half way through and don’t have a drift long enough to tap any more.

The engine was sitting around without a valve cover for several months. I’m curious if this could cause the difficulty in removing the shafts or if I’m pretty much guaranteed a warped/junk head.

  1. It seems that the rocker arms only contact the mid-90% of the cam lobes. Shouldn’t it be easy to tell how worn the cam is just by how much of a dip there is between the middle and the 2-3mm edges? The cam I’m looking at looks fairly flat, though I haven’t pulled it to measure yet.

Thanks for any feedback,

Som

#2

Worked on this some more last night. I got the exhaust shaft out, but had to hammer it out almost the whole way. The intake side came out mostly by hand (needed to be tapped past the first two tunnels). On the exhaust side, I realized that I was able to pull the shafts out by hand (with moderate effort) when the end wasn’t going through a tunnel.

I think I mushroomed the end.

When I started tapping it out, I was using a 3/8" extension as a drift. I noticed after the first couple dozen taps (which had only moved the shaft past the first rocker) that I was damaging the shaft plug (not the gasket plug, of course – the plug in the end of the shaft), so I switched to adding a 12mm socket to the end of the extension (which was roughly the same diameter as the shaft).

Assuming I did slightly mushroom the rocker shaft, I have a few more questions:

  1. Is this a big deal other than it being a pain in the butt to install/remove? It turns out the intake shaft didn’t even have the plugs on it, so I’m thinking I buy 4 new plugs. Not entire sure how to remove the one that’s there, but I’m guessing it shouldn’t be too hard.

  2. Any problem with just grinding down the end of the shaft a tiny bit to help it go back in?

Som

#3

I didn’t know the shaft end plugs could be replaced. Can’t be too hard to get some replacement shafts. Folks throw away thrashed heads all the time. Email Shawn and ask him who may have a boat-anchor head. Then harvest the shafts out of it. If you can’t find any out there, Richard Bratton or I can probably square you away.

I don’t see a problem with grinding the tip of the shaft down a teensy bit. But how you going to do it w/o roughing it up? The roughened steel shaft would gouge the soft aluminum when you put the shafts back. It’d take a lot of work to polish the shaft’s end after removing some material.

Oil goes inside one or both of those shafts so the ends need to seal. If you damaged a shaft-end test it for leaks.

#4

I’m guessing the shaft end plugs can be replaced since it’s a separate part (#5) here and appears to be sold by a number of places. Guess I’ll find out. :slight_smile:

I find it odd that the intake shaft didn’t even have the plugs on there. Engine PO mentioned that a wet compression test indicated top end issues… wonder if this contributed to it.

Guess I can just pour oil into the shaft and see if any of it leaks out the bottom. Or should I use something with less surface tension at room temp?

As for the shafts, they’re apparently NLA now. ECS has Febi’s arriving in August. Everywhere else is out of stock. There’s always the head in the car, but I was hoping to leave that untouched until the last step in case I botch something with the head rebuild I don’t take myself out of the mid-June race weekend. I’ll hit up Shawn for a boat anchor. :slight_smile:

Som