212 Engine Rebuild?

[Deleted User]

After months of tracking down parts I'm almost ready to re assemble and find that the clearance between the valve stem and valve guide is almost .007. Taking into consideration the heat, at best clearance would be .006. The shop manual says .002 and from what people have said up to .006. Do I knurl the valve guides? Bore .030 the guides and put bronze inserts (+6 hours)? Or put it back together and drive it? After putting all this work into this engine, New rings, pistons, valve guides, valves, lifters, milling the head, porting the exhaust and intake I just want to get the engine back in. The parts were from Dale so I would think that everything should be a good fit. The play isn't as bad as it was from the old valve guides. The problem is the more people I talk to the more confused I get:huh:

hudsonsplasher1

Ottobethere wrote:

After months of tracking down parts I'm almost ready to re assemble and find that the clearance between the valve stem and valve guide is almost .007. Taking into consideration the heat, at best clearance would be .006. The shop manual says .002 and from what people have said up to .006. Do I knurl the valve guides? Bore .030 the guides and put bronze inserts (+6 hours)? Or put it back together and drive it? After putting all this work into this engine, New rings, pistons, valve guides, valves, lifters, milling the head, porting the exhaust and intake I just want to get the engine back in. The parts were from Dale so I would think that everything should be a good fit. The play isn't as bad as it was from the old valve guides. The problem is the more people I talk to the more confused I get:huh:

You could possibly have the wrong valves with the guides. The earlier 212's used the thicker valves 0.370 with guides to match and the later engines used the thiner valve 0.308. I believe you can use either combination in the 212's as long as the valves and guides are mated to each other. .002 is the correct clearance. Someone will chime in and correct me if I'm wrong.
Gene Birdsall.

Geoff

It depends whether you are using stainless stem valves or not. If the stems are stainless, you need that extra clearance as the stainless expands more. the Hudson Jet used two-piece valve construction, the heads were stainless and the stems were silicon steel. Don't ask me how they do this, but you can see the demarcation below the valve head. with this type the heads are burn resistant, and the stems fit the guides better and don;t wear the same. Modern valves are usually stainless right through. I have had several instances of bronze inserts and stainless stems where the valves just jam up as they heat heat up, so do be careful. It is also essential that you adjust the tappets with the engine thoroughly warmed up, as the valves expand longitudinally as well, and the expansion is different again with stainless or steel stems. Good luck
Geoff