Strange "Clanking Noise" at Idle
 

Hello Everyone,

A few weeks ago I purchased a 1954 Ford Customline with the 239 Y-Block and Ford-o-Matic transmission in what i thought to be pretty good condition. I've changed all fluids, new plugs, wires, points, distributor cap, condensor, and adjusted valve lash and I've got to say it seems runs pretty good. That said, I've been trying to find the source of a "clanking" noise at idle with not much luck and was wondering if the experienced folks at the Ford Barn might be able to point me in the right direction. Hopefully it's something simple like an exhaust leak or noisy water pump, as the other options aren't great. Here's a link to a video if it running just a few minutes after startup with the choke off. The sound goes away as soon as the RPM's increase even slightly, it really only exists around idle speeds.

https://youtu.be/VNWB_oXtzJg

Any help would be greatly appreciated, thanks in advance!
Vince


Update: Forgive me, I meant to post this in Late V8, apologies. Going to move it over there.

Re: Strange "Clanking Noise" at Idle
 

Narrow it down by removing the fan belt temporarily.

Re: Strange "Clanking Noise" at Idle
 

Fuel pump?? G.M.

Re: Strange "Clanking Noise" at Idle
 

Heat riser valve in the exhaust manifold?

Re: Strange "Clanking Noise" at Idle
 

It may have dropped a push rod [its not uncommon for a Y block] get a vacuum gauge and start from there.

Re: Strange "Clanking Noise" at Idle
 

does the noise change when you put it in gear or change when the rpm is changed might be a crack in the flex plate

Re: Strange "Clanking Noise" at Idle
 

Hi Everyone,

Thanks for all the suggestions. Going forward I'm going to attempt to reply in the correct thread (my mistake originally) in the Late V8 forum so as not to confuse everyone.

https://www.fordbarn.com/forum/showthread.php?p=1913952

A few updates:

- I've removed the fan belt which isolated the generator and water pump, issue still persists

- Using the longest length of tubing I had on hand, I listened to the fuel pump when running and it sounded fine to me

- The noise doesn't change in/out of gear, but does go away at higher rpms (by ear maybe a few hundred rpm more in enough to make it go away/drown it out)

- I did a valve adjust recently and used the method where I tightened the adjuster until the pushrods barely rotated, all pushrods looked good, none were dropped and none were bent.

- I played with the spring loaded valve on the passenger side of the "exhaust-crossover-pipe" (sorry not sure the technical term), but to no avail, it didn't really change anything.

I appreciate all the suggestions and advice, I'm going to keep chasing this down. Will head down to the parts store to grab a longer length of tubing/pipe to use as a makeshift stethoscope, hopefully that will help.

Thanks,
Vince

Re: Strange "Clanking Noise" at Idle
 

loose bolts on flex plate? sort of sound like a knock with every revolution

Re: Strange "Clanking Noise" at Idle
 

Sorry for the stupid question, but am I able to get to the flex plate bolts with the Engine and Transmission installed in the car?

Re: Strange "Clanking Noise" at Idle
 

I hear the same and it does appear to be coming from the back.

Re: Strange "Clanking Noise" at Idle
 

I'll fire it up in the morning and take a closer listen to the area around the flexplate. If I can get it on a lift, I can probably answer my own question about accessing those bolts :)

Re: Strange "Clanking Noise" at Idle
 

Yes if its an early air cooled there should be a plate at the front unbolt it and you can check each bolt as they'll be a few as the torque converter is bolted together. you'll have to turn the engine over to get to each lot.

Re: Strange "Clanking Noise" at Idle
 

Fantastic, thanks a million, i'll have a look tomorrow and report back. 75-85 ft/lbs of torque on each correct?