'37 115C valves

Posted by tsherry On 2020/12/29 19:18:32

I've had valve issues since I bought the car in April 2019; I was never able to get it idling smoothly and starting it was an issue. Today I took the deep dive, after fruitless attempts to get the valves adjusted to spec, and decent compression across all cylinders. The car had been sitting from probably 2009-2015, and after fluid changes, plugs and points started up with a little hesitation, understandable due to the hibernation. We've put maybe 30 miles on it in 2019-20, when not rebuilding the suspension, brakes, etc.

What I discovered:

--Intake valve stems in #3 and #5 were gunked up something fierce, obviously keeping them open enough against the guide, it appears. Others weren't much better. Exhaust valves were all gunk-free, but had wear from the guides.

--Most of the valves are "Packard" script with a slot in the center--one valve has been replaced and is in nearly perfect shape. The other valves have wear on the stems than is significant--I think I'm replacing the whole set as a result. Some have pitting on the stem; other serious scratches and wear at the spring retainer. The seats all look fine, and no evidence of burned valves. The engine at some point had been rebuilt, but no idea when. The cylinders still show hone marks.

--The guides have a little bit of play. What is 'acceptable' in terms of play?

--The adjusting bolt on the valve lifters as I recall is supposed to be convex. Mine have worn to the point where they are concave where the stem meets the bolt. I assume I can recondition these to a convex condition with some careful work on a grinding wheel. Given the condition that they were in, it's easy to see that it was impossible to get an accurate adjustment with feeler gauges since the stem was sitting in a 'hole' in the adjustment bolt.

Any advice?