Okay now what ? Rod knock on a 50 mile engine /

[amceaglesx4]

So I googled for curiosity and found off timing way out of whack can cause a knocking. Anybody been down this road before ? Also saw fuel octanes can do it as well. Anybody have the 68-232-4 comp and if so what are you timed at ? Thanks

[optmaxx]

Is it still knocking? Post a vid to begin with. Upload it to youtube, then post the link. Did you notice anything weird with the cylinder walls?

[amceaglesx4]

Yea lol wtf. I'll try to figure out how to video and post. The guy who built it is coming over Thursday to listen to it run. My experience with rod knocks are they don't knock long. Gotta be gas or timing related. Before I removed the cam and replaced it there was knockish at idle or cruising but nothing in deceleration or acceleration. I'm getting tired of this shit and should of just bought a stock crate 4.0 and called it a day.

[amceaglesx4]

Cylinder walls looked great. I still had cross hatching swirls on them.

[Torqsplit]

If your running an auto-trans, take a close look at your flexplate, they can often get damaged at engine install and will sound very much like rod knock under load. Just a thought tho. -

[amceaglesx4]

Thanks but is a 5speed. Good tip though.

[jeepxj3]

What valve springs are you using?

Is this a knock of the cam going back and forth? Spring and pin issue? Main bearing with the thrust portion?

[amceaglesx4]

I'm not sure lol. It sounds like its more under the valve cover if anything. Its hard to tell . I heard you can pull a plug one by one and if the noise dissipates or stops it tells you what cylinder. Also heard of this timing knock thing.

[optmaxx]

I'm not sure lol. It sounds like its more under the valve cover if anything. Its hard to tell . I heard you can pull a plug one by one and if the noise dissipates or stops it tells you what cylinder. Also heard of this timing knock thing.

When you assembled the cam, did you put the spring and pin back in the cam bolt? Is the distributor held down with the hold down clamp?

[amceaglesx4]

Yes and yes. I'm running stock valve springs. Don't know if it matters due to springs or not but I had a three angle valve job done.

[jsawduste]

That is a hell of a lot more lift then I would run with stock springs. But then I don`t know what your installed height is..........

Just my opinion.

[Torqsplit]

If you mostly notice this on transitional-load, slight accel/deceleration, you may have a wrist-pin or bore tolerance issue. Probly not what you want to think about on a fresh build, sorry. During really cold weather i get piston slap on mine until it achieves a good heat soak. It has higher mileage these days and has become more pronounced over time.

[optmaxx]

Yea lol wtf. I'll try to figure out how to video and post. The guy who built it is coming over Thursday to listen to it run. My experience with rod knocks are they don't knock long. Gotta be gas or timing related. Before I removed the cam and replaced it there was knockish at idle or cruising but nothing in deceleration or acceleration. I'm getting tired of this shit and should of just bought a stock crate 4.0 and called it a day.

Hopefully it's something simple. Unfortunately, sometimes you can't see cylinder wall scuffing from the top with the head off, sometimes you got to look at it from the bottom with the oil pan off. Also, sometimes piston scuffing doesn't show on the walls, also when I had piston failure, the sound seemed to travel up making me believe that it was a valve train issue. But having someone listen to it is a start and posting a video here will help because people can guess what it is, but all you'll get are guesses without us knowing what it sounds like.

Maybe it's normal? Here's a thread that people concluded that are normal noises for Jeeps. Some Jeeps are quiet, some are noisy, it depends on the clearances I guess:
http://www.jeepforum.com/forum/f11/4-0l ... n-1377536/


Here's a thread by a member that had a bad piston knock, it was pretty loud:
http://www.jeepstrokers.com/forum/viewt ... f=5&t=5015
https://www.youtube.com/watch?v=nnW-15Eeq50
https://www.youtube.com/watch?v=gzslg8owJ5s

[amceaglesx4]

I'll try to figure out how to load a video. Symptoms before I replaced the camshaft and lifters were knocking or whatever sound was noticeable at idle and cruising. On acceleration or deceleration the engine was quiet. That's the best I got right now so what problems could that eliminate off the bat ? Also pulled plug wires one by one last night and the sound didn't change. I do know some plugs have electricity running through them lol !!!

[optmaxx]

Yeah getting shocked sucks, I forgot that you're running a carb cause I was going to suggest unplugging the injectors, but that won't work obviously haha.

It's just like posting a pic. Take the video with your phone, connect it to your PC, drag the video to your desk to if you like, create the You Tube account if you don't have one, and just follow the instructions to upload; I think you can drag and drop files that you want to upload now on You Tube. Afterwards, copy and paste the link to a new comment.

If the ring gap wasn't checked, you could possibly have a, or some broken rings? If the the wrong size rings were used like metric rings with pistons that require standard, then you could have broken rings too, ask me how I know haha, but your mechanic assembled it so that's probably not an issue. Could it be possible that your rockers are rubbing against something in the valve cover because of the bigger cam?

Since you're running a carb, I guess it may be a fuel issue? I don't know anything about carbs, but since you're running a carb mod with that horseshoe intake, you may be right.