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I ordered and received a used KD700 spring compressor and went to work raising the valves in the rear section as it seemed that the noise was greater there. I plugged the oil drain holes in the block as a precaution against something falling into the crankcase. I decided that I would use short sections of ?" steel rod about 2.35 inches long to keep the valves up and to used thin wire to keep raise the tappets up and off of the cam shaft. Things were going along great except when I got to the exhaust valve for cylinder number six. On that valve the spring raised up but the valve did not move. Conclusion is a bent valve stem.

Next steps will be to remove the head and replace the valve and guide. Since the valve is stuck, I would readily welcome thoughts on how best to remove it and any other inputs that might save me anymore grief.

It would seem that the valve probably hit the head, which caused the stem to bend. After I get the valve out and the guide & valve replaced, I'm going to lay the head in position without a gasket and manually turn the engine over to ensure that no other valves are in danger of hitting the head.

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I'm hoping the valve was stuck in the raised position and the lifter was just moving up and down against no fixed resistance, thus making the noise. Otherwise I'd be very concerned about what might have happened to the rocker arm and perhaps the camshaft lobe.

Anxiously awaiting your observations after the head is off. If you only need the smallest amount of clearance for a valve, a bit of grinding with a Dremel has saved some folk from the search for a replacement head. If the valve is indeed bent from hitting the cylinder head, the bend may be above the guide and you should be able to just pull the valve out - at worst a slide hammer puller. And I wouldn't assume that the guide must be replaced - check it out first.

Got side tracked as I needed to work on the 55 Caribbean and doing some woodworking (made a wood desk for our great grandson). Anyways went back to the '32 and its valve train noise. I haven't removed the #6 exhaust valve yet, but with the head lifted about 2" I don't see any signs of the valve hitting the head. Also, another valve seems to be stiff. I'm thinking that it may be a lubrication issue. The rocker arms, rollers, and seats all look good as does the cam shaft.

I think I remember that the original engine came with stamped rocker arms and mine has forged ones. I also think that I remember that when switching to forged arms there needs to be a change to the oil system. Can anyone out there shed some light on the matter? In addition, when I adjusted the valves, there was very little oil in the tappet oil galley.

Any and all thoughts on the matter would be greatly appreciated.

The service note about the rocker arm lubrication is in the service letters, I'm sure you can find it if you look but I have it scanned on my PC and when I get back to it later this evening I'll put it up if no one has beaten me to it.

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Marty,

Your valve chamber looks very dry, did you wipe it down? There should be a film of oil covering everything inside along with some pooling of oil on the chamber floor.

I'd also check the valve stem clearance to the guides. If someone replaced the guides and didn't check the clearance after the guides were pressed in the lack of proper clearance could be an issue. Pin gauges are an easy way to check the guide bore size.

Also if the motor sat for a period before running and the stem to guide areas were not lubricated properly you could have some corrosion causing binding.

The rocker arms receive pressurized oil thru holes in the crankcase that exits into the aluminum casting holding the rocker arms together. Thru the casting it goes into the hollow rocker arm shaft. If no one took apart these assemblies and cleaned out the hollow shaft it may be plugged. The large screw on the end of the rocker arm assembly can be removed to get to the hollow shaft.

Regards,

Dave

Also, make sure the gasket between the rocker arm assemblies and crankcase has a hole for the oil passage. I saw one where a previous owner cut his own gasket and didn't have a hole for this passage.

Dave & Dave,

Thanks for the inputs on the rocker arms. I did not wipe down the valve chamber. I'm tying to remember back when I adjusted the valves if there was oil or not. I would have thought there would be oil flowing in the are, but I don't think there was.

At this point, I plan on inspecting each valve and it's stem. I'll measure the stems and s probably get a reamer and ream each guide. Before putting it together, I'll probably lap each valve.

Other thoughts on other things I should check or doing when it comes to valve stem lubrication?

If both the valve face and the seat were machine-finished, hand lapping is typically not recommended as the resultant surface finish will be inferior to the machine ground surface. But if you now ream the guides, you may change the valve seating so perhaps best to go back and recheck and perhaps lapping will now be necessary. Time was, you always reamed the new guides after installation but it's been a very very long time since I installed today's guides that it needed reaming for proper fit.

One way to measure guide ID is with something like a Starret bore gauge.

I'm also concerned about the lack of oil within the valve chamber.

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Marty,

Checking the valve seal with Dykem or Prussiam blue is a good way to verify the seal if you replace / ream the guides. Both these materials can be found in Tool Supply houses or McMaster.

Dykem is thin like paint, brush it on the seat and apply some hand force to the top of the valve, turning it 1/4 turn. If you're in contact all the way around the blue will be removed along the entire seat area, and you have a good seal.

Prussian blue is applied to the valve in a thin coat, then do the same thing. You're looking for transfer to the seat.

The lack of oil in the valve chamber still bothers me.

Dave

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Havent read this complete thread so might b asking something thats already been asked/answered.
DOES THE VALVE ROTATE using little torque ? If not, guessing its just plain stuck. Ethanol Gas loves to do this. Ive had some engines that u would think the Valve & Guild r welded together.