UOP
Well-Known Member
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]
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]
