Engine builders/Gurus, I need your help.

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UOP

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Ok so here's the deal, and this is slightly embarrassing. For 3 years I haven't been able to figure out a tick that a buddy's 383 has been making. Seriously, 3 years, but we've made no progress at all in this time, so be warned this is a long read because this will be a lot of info.

What's happening is that there is some sort of tick coming from what we think is the valvetrain on the passenger side of the engine, mostly around cylinders 6. If you listen to the engine with a stethescope, the tick can be heard all around the passenger side head area, but the loudest is on the head, where the intake manifold meets it, in between cylinders 4 and 6. It is also loud down near the bottom of the head where it meets the block, but on the head between #'s 4 and 6 is loudest.

Still listening with the stethescope, you do not hear the tick on the valve cover, and listening to areas inside the head (around the springs, pushrods, etc) does not make the tick louder.

Originally we thought we had a pushrod hitting the head somewhere. At the time the engine was running Hughes adjustable roller tip rockers with a set of their custom 3/8" pushrods that looked to be very close to the head intake ports. It makes sense right? The noise we're hearing is right there where the #4 and #6 intake pushrods go up into the head. So, we ground the head to make clearance. We saw no obvious markings on the pushrods (we even tried painting them to make it easier to see), but it was for nothng. No luck, still ticking in the same spot, and still just as loud as ever.

Still thinking it has something to do with the pushrods, or possible the rocker design, we decided to try installing the stock rocker assembly. With this setup there is miles of room around the pushrods because they're longer and narrower. Great, the tick should go away, right? Nope, still there. This was after 2 years of adjusting, and adjusting on the the Hughes rockers, thinking we didn't have the preload set up correctly.

Now if we weren't already confused (and frustrated), we started to think it was a lifter. By this time we had already determined that the cam did not get wiped, and the lifters all looked ok with a good wear pattern on the tips. The lifters were also checked to make sure they were still slightly convex, and they were. Still everyone we were asking was telling us that it was because Comp lifters were used, and they are noisy, and that there was a bad lifter somewhere. The reasoning was because the tick is loudest at idle, but seems to go away as the engine revs, so it must be a lifter right? So, on the recommendation of some others we installed a brand new set of Sealed Power lifters, broke the cam in again, and again it was for not. Same tick in the same spot.

Seriously, we have no clue where to go from here. On top of what's already been mentioned, we've done countless other tests to try and figure it out. Here I'll just list random stuff out to help keep this from getting so long nobody will read it.

- Vacuum gauge doesn't show anything out of the ordinary. Low-ish vacuum, but no weird bouncing or rythmic movement on the the needle.

- It is not an exhaust leak.

- There is no coil bind or retainer clearance issues on the heads.

- The rocker doesn't hit the retainer.

- Pulling a plug wire does not change the sound of the tick at all.

- Putting pressure on the rockers while running does not change the sound

So, what else could it possibly be? Any suggestions at all? I've got a couple videos to take a listen to. To keep the sound quality I added them to my website. If you've made it this far, thanks for taking the time to read my little novel. Hopefully we can get this worked out. It's been a problem for far too long.

[ame]http://www.loyaltysystemsllc.com/EngineTick02.mp4[/ame]



[ame]http://www.loyaltysystemsllc.com/EngineTick.mp4[/ame]

 
Burnt valve? But that definitely sounded like a "clack" when you turned it off in the first video.
 
Sounds like a header leak to me. Did you look real close header flange where it bolts to head? If it had burnt valve it would have a bad miss. What pistons are you running ? Could be piston slap. Does tick change as engine warms up?
 
No apparent header gasket leak, checked several times.
Vacuum gauge does not indicate a burnt valve.

Sorry. I forgot to tell you about the combo.
383 stock bottom end.
440 Source Stealth Heads / Currently using stock rockers
Comp Cam XE275HL 275/287 525/525
Edelbrock Performer RPM
Quick Fuel 750 VS
 
Can't get the audio to download but... I had trouble with a fuel pump rod once that gave me noise in the passenger side of the block below the head just wonderin.....:blackeye:
 
Hows the oil pressure at idle hot? Kinda sounds like a lifter. How are you adjusting them?
I try to adjust hydraulics to the center of thier travel. Just my 2c
 
Oil pressure hot at idle is ~20. Currently there are non adjustable rockers installed, but even when we were running adjustables we weren't able to eliminate the tick.
 
This may have nothing to do with your problems but in my younger days I put an engine together with the pistons notch facing the wrong direction and it made a ticking clapping sound when it ran. Lesson learned lol!
 
This may have nothing to do with your problems but in my younger days I put an engine together with the pistons notch facing the wrong direction and it made a ticking clapping sound when it ran. Lesson learned lol!
another good possibility
 
I had the same thing going on for years. The car was never driven hard and didn't go for long distances and really didn't get all that many miles in a year. I did every thing I could to stop that tick. I changed out the rockers in the noisy area, cleaned and checked the pushrods, brand new cam and lifters, oil changes, oil additives, blah, blah, blah, it went on forever. The piston had developed a crack from the top ring groove up to the top of the piston and the piston would just tap the head enough to make a noise and the crack was just too small to see when I had the head off. Long story short, the piece finally worked free one day and block and one piston trashed.
 
I don't believe it's bottom end noise, and here's why, though I could still be totally wrong. This engine was not a fresh build. All we did was upgrade the intake, cam, heads, and valvetrain. The engine was in perfect working order before we did the upgrade, but we noticed the tick right away after idling the the motor down after cam break-in. At first we thought it was just a lifter that wouldn't pump up but it never went away.

One thing to note is that we did check the piston to valve clearance and there they're not even close to hitting each other. The pistons are way down in the hole. Also, when we removed the heads to clearance them for the pushrods, we checked inside the bores and saw nothing that would throw up a flag.

We are pretty certain the cam lobe isn't wiped. As I mentioned in the first post we tried swapping the lifters and the ones we took out looked great.

We also don't believe it's a torque converter bolt. The tick would be much faster wouldn't it?
 
When you wrote pulling a plug didn't help, did you mean pulling the wires, like one at a time didn't change the tick? I thought maybe a tick could be the result of a spark going to ground where it shouldn't be.
 
Yes, that's what I meant, pulled one plug wire at a time with no change in the noise whatsoever.
 
How about a porous casting or hairline crack in here?
 

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I did have a mystery tick on my father inlaws chev 350. Turned out to be a cracked flywheel...
 
When you had the head off did you try rocking the piston at TDC.

No I did not.

How about a porous casting or hairline crack in here?

The heads that are currently being used are 440source aluminum. I wouldn't have thought to look there, what would the problem be? Could you please elaborate?

I did have a mystery tick on my father inlaws chev 350. Turned out to be a cracked flywheel...

I wouldn't think so, wouldn't the tick be much faster if this were the case? Same as a torque converter bolt coming loose. I'm not automatically dismissing this as a possibility, it just seems the tick is much too slow.
 
The heads that are currently being used are 440source aluminum. I wouldn't have thought to look there, what would the problem be? Could you please elaborate?

Sorry, i don't know how i missed that:violent1:. Stock style heads have the space over the heat riser passage, but those do not.......again, sorry.
 
Got some news, though we still haven't figure it out. We decided to take the head off and take it to a machine shop to see if there was possibly something wrong with it, like a bad valve job or loose valve seat or something like that. Well, it came back with a clean bill of health. Looks like it's something in the shortblock somewhere, though it sure seems like a valvetrain issue.

I do have a question. What path does the oil take in a B motor? Just a guess, but is it oil filter -> oil pump -> mains -> cam bearings -> lifters -> rocker shafts? The reason I'm asking is I'm wondering if it's possible we're losing oil pressure to the lifters for # 6 and 8. I seem to remember when we swapped the cam that the cam bearings looked like they've seen better days. Is it possible oil pressure is bleeding off at the cam bearing, making it impossible for the lifter to pump up enough to hold up to the faster lift and spring pressures with this combo? The engine shows good oil pressure on the gauge (60+ cold, 20 @ hot idle), but maybe that's not the whole story.
 
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