The Stovebolt Site Forums The Shop Area Engine Shop Ticking Clicking, but only sometimes

235 engine, I adjusted the valves, and checked them again today, and they are all spec ok. .006 and .018. I'm hearing a clicking ticking sound that sounds louder than valve clatter, but only at one particular relatively low part throttle rpm. It sounds like something is loose, or rattling around, Almost a clank, but only at one part throttle setting. But that, of course, is normal drive down the road speed. Any ideas or suggestions what to check next?

oops,, I just read

dump her or work on our relationship? 235 woes

about lifters and lifter bore? might I have the same issue?

Stock engine setup and components?

Yes, to the best I know. Just finished tune-up, points plugs wires etc. It's running very well. but this new noise has me concerned.

Like a chatter sound when your around 2200-2500 ish rpm when holing steady on the gas?

I have just gone thru a similar sounding issue.

After pulling the engine and examining stuff , I found the fibre cam gear was worn enough to have excessive backlash to the crank gear.

New fibre gear fixed my noise

Yes, wolfcub. steady on gas clatter at low 2000 ish rpm.

and dusty, sounds like I should check that gear. Must I pull engine? Or is it just up front by the water pump?

One quick item to check would be the heat riser valve in the exhaust manifold, the sheet metal flap can come loose causing odd noises.

Before pulling the engine apart, use a long stick and place it on the timing cover and the other end up to your ear, then hold the throttle open. You should be able to hear the chain hit the cover pretty clearly.

Joe

there is no chain in these engines

fibre cam gear???

Real stovebolt 216/235/261 truck engines did not use them - real truck/Corvette stovebolts had metal/aluminum cam gears.

But, I think that Pre '68 Dave uses fibre cam gears on all rebuilt stovebolt engines (for less noise).

I would not say I use fiber on all, but I prefer them.
If you check run-out closely on an aluminum gear, and make sure it runs true, they will be almost as quiet.

I knew that about gears, not sure what I was thinking. The stick or screw driver is still a good easy tool to find a noise.

Joe

Is it written in stone somewhere that all truck engines came with aluminum timing gear?

What years and engines, Carl?

I referred to 216/235/261 USA truck engines (and the Corvette 235).

I doubt that it can be found to be written in stone, but most likely it is printed in ink in Master Parts Catalogs (up to 1957 is on-line - http://chevy.oldcarmanualproject.com/ - Group 0.736).

I do not have a MPC for trucks after 1957.

http://www.oldchevytrucks.com/cart/product.asp?prodid=ME439A&i=10423|||||

A bent pushrod can make an intermittent noise.

You seemed to answer yes to all my questions about when and how the sound comes about. Granted your running a stock distributor but as soon as I disconnected my non stock vacuum advance the sound / chatter went completely away. No change in performance that i can feel or hear also. The instructions even say that possible disconnection and or alterations to one or both carbs might be required to fine tune my setup.

Thanks, I'll check the pushrods, and try disconnecting the stock vacuum advance.