rebuilding heads, ever done it ?

[dubie]

Has anyone ever done their own heads? Just replacing all the parts with the excpetion of guides? Just wondering how difficult it is

And what bennefit is there to having a valve grind done?

[ckhd]

Don't skimp dubie.

I've rebuilt my own, but it was when I worked at NAPA with a machine shop in the back. I put new bronze guides and a 3-angle grind on both the seats and the valves.

[dubie]

MY budget is damn enar gone now and i just found out my heads are cracked, so I am just exploring some option here bud I was just curious because they don't look overly difficult to take a part.

[ckhd]

The benefit of a valve job is that it will true up the surfaces of the valves and the seats. Make it seal like it should.

If you don't do a valve job, be certain that you keep the vavles in the same hole. If you mix them up, you will be sitting on a time bomb. The wear patterns won't match anymore and it will cause premature failure.

It's not that difficult if you have a valve spring compressor. I think the compressed air in the cylinder is a bad idea (too much for the rings, imo), but you could probably rent a good one (the kind that reaches to the underside of the head to hold the valve while it squeezes the spring so you can remove the keepers).

They are just an assembly of parts. No different than anything else.

One tip... when you go to put them back together, get some engine assembly lube. Use it to hold the keepers in place when you let the pressure off the spring compressor.

If you get new valves, get a valve job done.

[Mike C]

They are not difficult to take apart, but seldomly is that all that is needed. You can do new seals and lap the valves as well as shimming the springs to restore function. At best this is a temporary fix. "Pay the man now, or pay the man later." If this is not your only transportation, you will be ahead to pay the man now... If it is, I'd just try and get a decent running motor from a newer vehicle and drop it in over the weekend, or at least pull the heads off and swap onto your shortblock.

[Randy70C-10]

You don't even need valve spring compressors to remove the valves. Just tap the top of them good with a mallet and they'll pop right off.

[Lippyp]

I have refreshed a few heads in the past, lapped the valves back in, new valve stem seals, decarboned and generally cleaned em up. (not Chevy engines as this is the first I've owned). The most important thing is to check for any wear in the guides. If there is any real side to side movement in the valves in the guides time for new ones and a trip to the machine shop. If you have to replace valves you'll need to get them ground in by a shop. If the valve guides are OK and you just have mild pitting on the valves/seats then you can just lap them in with grinding paste. I actually use an electric drill to do this very carefully, a lot quicker and less blisters than the old sucker on a stick thing. Just make sure you get every trace of grinding paste off afterwards. Keep the components, valves etc in numbered sets so you put them back in the same place. I just use a piece of board with numbered holes in it to store the valves and springs, and small bags for the rest.

It's not hard, just keep everything clean and don't mix anything up, it takes a few hours per head. I even polished the ports in one Triumph head with some small stones mounted on a flexible shaft, the thing went like a rocket afterwards!