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I hear a knocking noise which I think is in the valve train somewhere. It seems to be coming from the rocker lever assembly. How much trouble is it to remove the assembly to inspect it and how is this task accomplished?

Probably a worn roller pin, hopefully they are still available from Egge (they had discontinued them once a while back). You can remove the assembly without removing the valves.

Dave,

Thanks for getting back to me so quickly. I read your input on this subject. You do not mention removing the manifolds. Is it correct to assume that they need to be removed in order to remove and install the assembly?

The ones I've removed have been on downdraft engines, so can't advise about manifold removal (or not).

I decided that rather than trying to use the spring compressor and fight the manifolds it would be easier just to remove the manifolds.

If I can locate a compressor I'll be tacking the job this weekend. Otherwise I'll break down and buy one. However, my favorite mechanic who works on our newer cars has his father's tools who was also a mechanic (guessing 50's to 80's time frame). Hoping for the non C Clamp style.

EGGE still lists the pin and roller.

I replaced the pins on mine, they had about .03-.06 wear. The fully hardened roller on mine had a thin brass sleeve between the roller ID and pin.

Don't know if this was original or a past attempt at a fix. I had the ID bore of the EGGE rollers opened up and pressed in some Torrignton needle bearings. The EGGE pins were also hardened and had a finish / hardness acceptable for the needle bearings.

Wear of the roller or pin is going to decrease total valve lift, but I didn't have any noise from the worn ones.

Any addition info on the knock would help diagnose the problem.

1. Does it occur in sync and increase with engine speed or less than engine speed?

2. With the engine running short out a plug at a time and see if there is a change. A hard knock could be cylinder related (wrist pin knock, rod knock, piston slap).

3. Pull the timing chain inspection cover, with the engine idling shine a light inside and watch the chain / generator gear. There is a spring in the timing cover that is supposed to apply a load to the generator gear to eliminate end play. If the spring is broken / missing the gear would be shifting back and forth.

4. If you have the rocker assembly removed gently apply some force on the camshaft to check to see if it has excessive axial play.

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Dave,

Thanks for info on what's available from Egge and your thoughts on the noise.

I took over the car's restoration from the prior owner who had the engine rebuilt. It has about 10 hours on it since the rebuild.

When I started the car is when I first heard the noise. It ran with a rough idle. I did not rev it up or increase the engine's speed. I shut it down after about 10 or 15 seconds. I restarted it and it seemed like the noise was coming from the rear of the engine around where the tappets and rocker lever are. The noise would briefly disappear and when it did the engine idled smoothly. I only let it run for about 30 seconds and did not rev it up for fear on creating further issues. I also noticed that the aspiration noise through the carburetor was different when it was missing and not missing, which might indicatate a sticking intake valve.

I have pulled the manifolds and the mechanic had several C Clamp spring compressors. It seems that the other style would be a better choice and I have one coming to me that I found on EBay. .My plans are to pull the rockers and inspect them as I do not want to damage the cam. What I find there will determine if I pull the head and check for issues with a tappet or valve.

When I remove the rocker arm assembly\ies do I need to be concerned about the tappets falling through to the bottom of the engine?

When I remove the rocker arm assembly\ies do I need to be concerned about the tappets falling through to the bottom of the engine?

I don't believe so, IIRC the lifters go into the cylinder bore casting from the underside and are retained when the crankcase is attached.

Marty,

Sorry I couldn't get back to you earlier, been busy at work.

The lifters will not fall thru into the pan, the hex nut is larger than the lifter body.

I found it easier to remove the valve springs and slide the valves up, holding them up with clothespins. Do the same for the lifters, it makes removing the rocker assembly easier.

Check the top of the lifters, the adjustment screw usually wears on top. The ones shown in the attached picture are worn and should be refaced.

I ran into a problem where I couldn't get an engine ('32) to run properly. Drove me crazy for 6 months. I finally traced it to a bent cam. The cam had a twist in it and the base circle of a few of the cam lobes were not on the same center as the cam journals. The engine probably had a few stuck valves and when someone tried to crank it, it twisted the cam.

This made adjusting the lash impossible. Ended up pulling the cam and having it straightened and reground.

Hope this isn't your problem.

I ended up finding it by putting an indicator on each valve and measuring the lift as I hand cranked the engine. I adjusted the lash to zero first. When I saw the indicator moving .008 to .010 when the lifter was on the cam base circle and the engine cranked, I knew something wasn't right.

Regards,

Dave

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Dave,

Thanks for the picture & info.