Please Help with Knocking Noise Diagnosis

[Goose]

A couple of weeks ago I went to the track and while I was staged with my 2 step, I blew the driver side header gasket, causing the car to back fire a few times. Hearing this, I didn't race the car down the track, and I ended up just driving it home afterwards (about 5 miles).

I then took the car to a local shop to have the header gasket replaced. After the gasket was replaced, I could now hear a knocking sound coming from the driver side valve train (sounds as if I had a slight exhaust leak). The knocking sound increases and decreases with the rpms, and it never goes away, but the cars performance has not gotten worse.

After reading around this forum and the web, I began to suspect (or at least hope) that the problem was a collapsed lash adjuster. The car was also about a quart low on oil, so I am thinking that I might have starved a lash adjuster and caused it to fail.

Today I took a stethoscope to the cam cover and the valve train sounded normal except over the #5 cylinder. Here I could hear a much louder sound. So I took off the cam covers, and now I want to check to see if any of the lash adjusters are bad. So my question to those who know is, what is the proper method for verifying if I have a bad lash adjuster? Is it just a matter of having the base of the lobe on the follower whose lash adjuster I am checking? If so, am I then checking for excessive wiggle of the follower?

Thanks for any input which anyone might have, and sorry that its a bit of a long read, but I wanted to provide as much info as I could about how the problem happened.

 

[bluebloodbundy]

If it starved for oil its possible there is some damage on the cam journal under the cap. If you have the tools and know how , you could pull the cam and do a visual inspection on each component. you should be able to stethescope each cap with engine running(be careful of oil sling from timing gear) We have valve cover cut in half so we can cover the gear and not sling oil all over the engine bay.or you could bring it to a good shop and have them check it out

 

[bullitt boy]

I know this is a stupid question , but did you check the plug? Mine was making the same thumping heartbeat kind of noise turned out to be a bad plug.Kind of basic but worth a try.

 

[Goose]

If it starved for oil its possible there is some damage on the cam journal under the cap. If you have the tools and know how , you could pull the cam and do a visual inspection on each component. you should be able to stethescope each cap with engine running(be careful of oil sling from timing gear) We have valve cover cut in half so we can cover the gear and not sling oil all over the engine bay.or you could bring it to a good shop and have them check it out

Thanks.

I know this is a stupid question , but did you check the plug? Mine was making the same thumping heartbeat kind of noise turned out to be a bad plug.Kind of basic but worth a try.

I haven't checked the spark plugs because the cars performance hasn't degraded, but I will look into that. Was you spark plug physically damaged or was it just failing?

 

[bullitt boy]

Cars performance did not degrade on mine just as you explain. Funny it was # 5 cylender as well. Tip was almost inside the threaded part of the plug ,ceramic was gone.I changed the plugs no more heartbeat sound. Has your car " Back fired"?

 

[Goose]

Cars performance did not degrade on mine just as you explain. Funny it was # 5 cylender as well. Tip was almost inside the threaded part of the plug ,ceramic was gone.I changed the plugs no more heartbeat sound. Has your car " Back fired"?

Yeah, when the header gasket blew while I was staged with the 2 step on, the car back fired a few times.

I think Im going to go to the car in a few and pull that plug. That would be awesome if that was the only problem.

 

[bullitt boy]

Hey Goose , Any luck?

 

[Goose]

The plugs were fine. I'm just going to replace all the lash adjusters on the driver side bank. The lash adjusters get in on Wednesday so hopefully I'll have them done for the weekend.

I was really hoping that it would be a bad plug.

 

[bullitt boy]

You and me both. Hope it works out keep us posted.