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BigKev,

Thanks for all the work you do to make this site what it is.

My 1 ? cents regarding the engine tick:

Your video is 17 seconds long; I counted approximately 25 "ticks" in 5 seconds of video.

This gives 5 ticks per second.

If we assume the engine was idling between 450 and 650 rpm, a "tick" related to crankshaft rpm should be in the range of 7.5 to 10.8 "ticks" per second, depending on rpm.

It would be helpful if you could record the exact engine rpm next time you fire her up and record video / audio.

If you're engine rpm measures 650 and your video records "ticks" at approximately 5 per second, this is a good clue that the noise is coming from something being driven at ? the crankshaft rpm since 650 rpm's at the crankshaft gives 10.88 "ticks" per second and 5 "ticks" per second is very close to ? of 10.88.

If the "tick" occurs at ? engine speed I would look closely at the valve train or any engine component being driven at or near to ? engine rpm (distributor / oil pump / engine accessory, water pump impeller), etc...

For example - Could the noise be a loose or missing distributor weight spring, causing the weight to hit the side of the distributor housing, loose valve seat insert, loose cam gear key-way, master link on the cam chain hitting something , a loose distributor drive gear / pin, etc...

Hope this helps, I had a problem setting vales on an engine that was traced to bent cam lobes. It "only" took me two months to figure it out.

Regards,

Dave

Dave, thanks for the info and suggestions. Part of the issue is the harmonics of the noise. Very hard to pin point the exact location. I have run a stetho all over the motor and cannot find that 'gotcha' place where it is coming from.

I remember that the distro had some back and forth play in the shaft. Not sure how much is normal. Timing appears to be steady and not bouncing around.

Never had the timing cover off. So not sure what the status is under there. To me the sound appears to come more from the rear as opposed to the front of the motor. But the harmonics in there have it sound like it is coming from everywhere.

I've run it with the fan belt and fuel pump off, and no change in the sound. So that elimate those items. I guess I can pull the distro and check for anything funky in the shaft.

BigKev,

Does the "tick" change when you short a plug wire? To eliminate piston, wrist pin, rod noise....

Your point on harmonics got me thinking, could the noise be originating from outside the engine and the block is magnifying / changing it. I had a 79 jeep Cherokee that had an engine "tick" that drove me crazy. I traced it down to a broken flex plate tab on the TH400 transmission. I was sure it was a rod knock.

Another "tick" I ran across was on a '30 Ford , the thrust bearing on the crank was worn so much there was enough end-play in the crank to bias the flywheel towards the back of the engine. One of the pressure plate bolts was just a little longer than the rest and it was hitting the bell housing.

If the "tick" is loud enough maybe pulling the plugs and spinning it over with the starter would show something.
Second thought when you turn the key off and the engine winds down does the "tick" continue?

Please send some CA weather our way, I just finished digging out from 48" drifts driven by 55 mph winds, and it's supposed to be 8 deg. F tonight. Some warm Santa Anna winds would be nice...

Regards,

Dave

Dave, I did pull one plug at a time. The idle drops a bit, but no change in the noise.

Also I have put the transmission in gear with the brakes on to load the motor, and no change. If it was a loose flexplate I would think the noise would change under load.

Any other ideas?

The starter is too loud when starting and you can here the klack noise at that time.

Get yourself a stethoscope and start hunting.

Already have one. Read above.

Probabaly the crank hitting the oil pump pick up screen if it has a floating screen. Drain a qt of oil from the engine to see if the clack goes away.

Quote:

Ring gear and starter gear mis-matched or misaligned? The continuing clack after starting can be ongoing interference between the gears... or the ring gear hitting somewhere. Bad spring could leave the starter gear just far enough out to contact the ring gear at one -- or two-- points.

These ideas go with your current best guess of the noise coming from the back of the engine. Another possibility back there is an exhaust pipe or draft tube hitting somewhere. They can set up some amazingly steady rhythms under the right conditions.

BigKev,

No change shorting the plugs eliminates piston, wrist-pin, con rod noise, and loading the motor should change the noise if it was the flex plate.

Good clue with the starter noise.....If the starter pinion / ring gear mesh is to tight the starter Bendix may not be disengaging from the ring gear. Or a bad Bendix that is not kicking the starter pinion out of the ring gear.

You may want to look at the Bendix to verify its condition and then cut some shim stock to mount between the starter boss and flywheel housing. If the pinion / ring gear mesh is tight the shim stock will open this up.

Another way to check this is to remove the starter, pack some clay around the starter pinion and bolt it back in. Remove the starter and check the thickness of the clay. You may have to spin the starter pinion gear our and tape it in position so you make sure it meshes with the ring gear when you bolt it in.

PackardV8's comment about the floating pickup screen sounds good, a quick and easy check by dropping the oil level. If the floating pump screen is stuck in position this may not show it. Dropping the pan may be required.

If dropping the oil level doesn't change anything, how about pulling the plugs and turning the engine over using a socket / breaker bar on the crank harmonic balancer nut? If the crank is hitting the non-floating pump pickup screen you may be able to hear it by turning the engine by hand.

K-D also makes a simple tool that hooks on the flywheel ring gear teeth to rotate it by hand.

sjdiscounttools.com/kdt2270.html

Your previous comment of having some distributor shaft side play - I've seen .005" max. shaft side play as a service limit it a few shop manuals for distributors with points.

Regards,

Dave

Quote:

Kev,

That pretty much ices it for me. At least that's where I'd look first. All in all, it would be pretty nice if that turns out to be the problem. You could even ignore it for a while!