DIY Valve Job at Home Continued

That was simply from a cheap set from Harbor Freight.

This is what I used to drill the hole through them.

I've read that a #70 - #90 jet size works well. The drill bit I had works out to be a #76 equivalent jet size.

I also broke exhaust bolts off in the heads taking the manifolds off. Here's a little trick that seems to work fairly well most times.

For a 3/8" bolt I use a 1/2" nut and it's placed like this and then welded to the bit of bolt. Now if you're going to use a zinc plated or cadmium plated bolt make damn sure you have ventilation and the smoke is blowing away from you. It's toxic.

The idea once welded, let the temperature equalize between the hot bolt/nut and the head, then squirt the bolt with penetrating oil and use a wrench on the nut.

Two of the bolts came out right quick, the third fought me for quite some time.

I cleaned the mating surfaces of the heads. Now to clean these because they were so bad required a lot of work and processes. First was a scrubbing in the parts tank, then a quick wash with brake clean outside. Then into the electrolysis tank overnight to get the rust out of the cooling passages, then into the walnut blasting cabinet. They are clean, inside and out.

For old junk and DIY they are showing promise.

The new valves, springs and retainers came in.

I spot checked the valve stems in few locations for tolerance and these are looking good.

This is after a quick lapping and the head seats and valve faces look really good.

New valve stem seals.

New springs.

This head is done.

Second head. Again the valve seat interface is looking very good.

Both heads are done sans paint. These should work really well. Out of pocket cost (including the drill/reamer) was 400 dollars. Not bad for DIY.

Now lets see what I can do with that block.