3.0 Tapping Noise

[81dmc]

So I finally got my 3.0 running. At 200*F, I'm getting 14-17PSI oil pressure as idle. At 2000, it's 55-60psi. Looks like that's book value for a 3.0.

Now I'm having a tapping noise. I put new solid rockers and reused original 3.0 cams when doing rebuild. Now I don?t know if my tapping is the rocker, I mean it certainly sounds like it, but could it be something else? I did run it at 2500 rpm the best I could. Maybe it's time to reset lash?



Also, getting a vibration at 1500 and 2500 rpm. I think the vibration is from the spec 1. It shakes at those RPMs.


The car currently sounds like one of my diesels lol.

[Jaybaybay]

Any particular reason why you didn't want to stick with the original hydraulic setup? One of the reasons I liked going to the 3.0 was the automatic lash adjustment. I'd run it with the valve covers off and see if you can pinpoint the noise source. If it ran quiet before the switch then I'd say that's where your problem lies.

The noise in the end of the video next to the block/front cover sounds like rpm (crankshaft) not camshaft speed to me.

[81dmc]

Any particular reason why you didn't want to stick with the original hydraulic setup? One of the reasons I liked going to the 3.0 was the automatic lash adjustment. I'd run it with the valve covers off and see if you can pinpoint the noise source. If it ran quiet before the switch then I'd say that's where your problem lies.

This engine never even ran before the switch. It had a cooling system mess and pitted cylinders when purchased from junkyard. Then some of the hydraulic lifters were frozen with no reliable replacement available. So it got new solid rockers, new liners/rings, new chains/guides, and new bearings.

I was still unsure whether to run those old lifters, but Josh B from DPI advised me to stick with the solid setup for reliability.


I wish I could run with covers off, but it would shoot oil all over the place..

[Dickey]

I use one of these for mechanical taps because I do not hear very well and I find the acoustic isolation is really handy:

https://www.harborfreight.com/mechan...ope-63691.html


Prior to becoming an old man yelling at clouds, I would just use a long socket extension and put my ear to one side with the metal touching the engine somewhere on the other.


Similarly, since I cannot hear very well, I also take a length of 3/8 fuel line with one end to my "good" ear and put the other over each exhaust port because I can no longer hear the difference between a bad exhaust leak and a loose rocker arm as most of my engines have pushrods. The rubber quells a lot of the mechanical noise from the engine and an exhaust leak is really loud on the port where it's coming from should that be the source of the racket.

[Delorean Industries]

Check rocker adjustment and listen to injectors. A loud injector can reverberate through the cylinder.

[81dmc]

Check rocker adjustment and listen to injectors. A loud injector can reverberate through the cylinder.

Rog. Going to check lash today. I actually pulled each injector plug one by one with no change to noise.

Going to also reduce my plug gap from .046 to .030 as I think the COPs in series might be giving me some lumpiness as well.

[81dmc]

During valve adjustment. Cams look good to me. Some rockers were a little loose.
4344A037-A5CE-462F-ADD9-AD65ABB55020.jpgD219B7A3-FB93-47F2-AAC7-BB44D3449842.jpg

After. Starting to think I have an exhaust leak, so I ordered new manifold gaskets.

[Ron]

$.02

Hard to say, but the tic(s) sounds quieter in the 2nd vid to me.

Since you think it may be exhaust leaks, try pulling the plug wires one at a time while it's running...

[81dmc]

I'm starting to get the feeling that my cam timing is off a tooth.

Why? Well manual calls for intake valve to begin opening at 14* BTDC. Cylinder 1 and 5 TDC can be referenced using TDC mark on crank pulley, and thankfully, I can see intake rocker for #5 clearly from oil filler.

I'm not seeing the intake valve beginning to open until after TDC.

I made a video. I call out the degrees BTDC for #5. What y'all think?

[81dmc]

So I pulled the timing cover through the night and retimed, and it's the same. It was timed right from the get go.

I guess I'll replace exhaust gaskets and just live with any noises that remain unless anybody has any ideas?