Thread: Gen I (1969) SBC 350 NEED HELP, TICKING SOUND

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First time post, but view the forum a lot and need a little help from you SBC guys. I have a 1969 SBC 350 ,DH heads, 4bl edlebrock, sitting in my 76 CJ5. Sorry, not your typical hotrod. But I have done a frame off restore, rebulit trans, and alot of work to the jeep. Engine has run great the entire time I have owned it, and I recently installed a new Edlebrock 1406 4bl carb to replace the previous 1406 that was on there (rebuilding and putting on another engine).

The jeep is not a daily driver, but last few times I had it cranked, I was fine tuning my choke/adjustment, etc.), also recently installed a new HEI distributor (little recent background). Wanted to add those two comments in case they are in some way related to sound, but I dont think it is. I took it out recently and heard a light ticking, not a deep knocking, but almost sounds like a exhaust leak sound. Have no exhaust leaks, and at first it sounded like it was coming from my bellhousing area. Ive cranked it and listened in different places, but the more I do it, I find i cant really narrow down a definite location. I hear it under vehicle, between bellhousing and flywheel, checked starter gear clearance, its ok, I somewhat hear it around and in front of the distributor on top of engine. It speeds up and slows down exactly with engine RPMs. Without trying to self diagnose myself like im at the doctor, where are the only possibilites I can come up with. Im hoping you guys can help me cancel out some possibilites, and/or point me in a direction that im not looking or considering. Im mechanically inclined but have not been through every engine's troubleshooting and want to try and limit tearing the whole thing down in search of something that could be simple.

First thought was i may have something loose in bellhousing/clutch/trans, pulled trans off and away from flywheel, still hear sound, so I can cancel that out.

Thought I may have a loose wobbly rocker, took covers off and they all seem to have the same amount of left/right play without any looking suspicious.

Thought it may be something hitting inside of bottom of oil pan, havent pulled it because its muddy and for some reason that gasket is a bi*** to get on and lined up. I also thought it could be oil pump in pan, but dont know much about that particular pump to know how that would fail or make noise. When I crank up, it does have oil pressure, but I have experienced low pressure at low idle (maybe below 20psi). but no erratic up and downs. also thought about where distributor shaft connects to pump, but im guessing if its pumping its ok?

I first noticed it when i was tweeking with my new carb, could I have a bad adjustment or advance or something that could make this sound. Im not real familiar with advance and how carb works with distributor, vacuum, etc. Also could any tweeks have affected timing?

Also, ive considered maybe something with flywheel, but have not pulled it and from just looking at it everything looks ok. Its a manual trans so i dont have torque converter or flex plate. Is there something else on the flywheel between it and engine shaft?

Front pulley on harmonic balancer wobbles a bit, but i think its a warped pulley, and it was like that when I bought vehicle, balancer looks fine.

I want to try and not tear everything apart, when it could be something simple i have not thought of, so Im hoping you guys can help, ask questions, ect. I do know it could be bearings in engine, but dont want to move that direction until i can cancel out the more simple possibilities. And it did start after I was messing with my carb, which I find a little odd, and I can hear it between carb and distributor, so its not just a below engine sound.

Thanks in advance for your help.

From an earlier post where you were trying to ID the engine, Tech pointed out that it was originally either a Powerglide or TH350 engine. Wondering about the pilot bearing/bushing in the crank, which indexes the tranny input shaft into the back of the crank?

Originally Posted by rspears

From an earlier post where you were trying to ID the engine, Tech pointed out that it was originally either a Powerglide or TH350 engine. Wondering about the pilot bearing/bushing in the crank, which indexes the tranny input shaft into the back of the crank?

As far as I could tell when I had the jeep transmission off, it has a bushing. Im not sure if it was previously swapped from bearing to bushing to accomodate t150 trans shaft. I know I would be able to tell if a bearing was bad, but as far as the bushing, im guessing its brass and they dont wear too bad, and it did not look like the outer surface had any space or play

with valve covers removed run engine and look to see if the pushrods are spinning-if not, cam/lifter wiped--------

Originally Posted by jerry clayton

with valve covers removed run engine and look to see if the pushrods are spinning-if not, cam/lifter wiped--------

I will try this, but ive never looked for push rods spinning, didnt know they did, so I have never noticed, thank you/

If it's not a cracked flexplate (because there is no flexplate) or the cam going south, then I would suspect an exhaust leak. They can sound like a tick-tick. Did you tighten the flywheel onto the crank and torque to spec while you had the trans out?

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Originally Posted by techinspector1

If it's not a cracked flexplate (because there is no flexplate) or the cam going south, then I would suspect an exhaust leak. They can sound like a tick-tick. Did you tighten the flywheel onto the crank and torque to spec while you had the trans out?

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Im not sure that I have a flexplate, unless it is mounted on the engine side of the flywheel. Not real familiar with a flexplate, but arent those with auto trans? I have never had the flywheel off, so never had bolts out. But that may be something to check, as the owner before me may have done that. Does anyone know torque specs for flywheel bolts?

Originally Posted by cgw3

Im not sure that I have a flexplate, unless it is mounted on the engine side of the flywheel. Not real familiar with a flexplate, but arent those with auto trans? I have never had the flywheel off, so never had bolts out. But that may be something to check, as the owner before me may have done that. Does anyone know torque specs for flywheel bolts?

What Tech's saying is that a cracked flexplate is one of the first things to check with this symptom, but you don't have one. Torque for your flywheel bolts is 60 ftlbs, using LockTite thread locker - Small Block Chevrolet V8 Engine Specs | Torque Specs - Cylinder Numbering - Firing Order - Distributor Rotation - SB Chevy 267 305 327 350 400 Cid

Sounds like you have a bronze pilot bushing, which I prefer over a bearing. They last just about forever.

Get a stethoscope and isolate the general location of the noise. Might be the timing chain, a rocker, a lifter,
a flex plate, or whatever. Then, once you isolate the general location, you can get more specific with the
find.

Originally Posted by robot

Get a stethoscope and isolate the general location of the noise. Might be the timing chain, a rocker, a lifter,
a flex plate, or whatever. Then, once you isolate the general location, you can get more specific with the
find.

I will try the stethoscope, the engine is loud enough on its own that its really hard to get an idea by sticking you head in the engine compartment.

And if you don't have a stethoscope a section of wooden broom handle works quite well.

Originally Posted by NTFDAY

And if you don't have a stethoscope a section of wooden broom handle works quite well.

I've got a big old Craftsman screw driver that's almost 2' long, 1/2" blade and an ear against the end of the handle works good to find noises, too. I'm hoping that Jerry's idea of a wiped lobe on the cam is not right, but that's a really good possibility.

Originally Posted by rspears

I've got a big old Craftsman screw driver that's almost 2' long, 1/2" blade and an ear against the end of the handle works good to find noises, too. I'm hoping that Jerry's idea of a wiped lobe on the cam is not right, but that's a really good possibility.

Whatever works. I've always used wood to eliminate the possibility of getting shocked or shorting something out and I've had too many vehicles that didn't have fan shrouds and sometimes I can be a klutz.

How about snow shovel handle???????

Originally Posted by jerry clayton

How about snow shovel handle???????

Works for me, any round piece of wood will do, all I've used for years.