Light Engine Tap Sound

[jdioguardi]

Getting my tranny swapped out after the DS put a hole in it a few days ago....but might as well inquire about all my Disco problems.

There's a light tapping sound that I hear sometimes from under the hood....and my idiot mechanic who mis-diagnosed my failed front DS (costing me thousands) also told me that I just need to put in heavier oil to prolong the life of the engine. In light of my recent experience, I frankly don't trust his professional opinion.

Ideas what the tapping could be? He says lifters.

Should I just use a heavier oil?

 

[ChrismonDA]

Do you have the 4.6 engine?

 

[jdioguardi]

Yes. 04 LRII SE7

 

[wheelen disco]

A internet diagnosis is ultimately impossible, there are many causes for such a noise and the 4.6 land rover is suspect for all.

Has it been overheated?

1.yes; the liners may have slipped

2. No; the liners still may have slipped

Have you been using proper oil?

1. Yes; well I think so, I use whatever jiffy lube puts in.

2. No; all rotating assembly's are suspect.

 

[listerdiesel]

Poor oil can cause the lifters to stop adjusting the valve clearance, a clogged lifter will result in excessive valve to rocker arm clearance giving rise to the tap.

A worn rocker arm or nose can also cause it, and there was an issue on earlier engines where the hardened tip in the rocker arm worked loose.

We run detergent oil 10W-40 in ours, we had a tap with a brand new block but believe it was dirty lifters. It has gone now, but took quite a few miles to clear.

An arcing plug lead (wire) can also sound like a tapping.

Peter

 

[pjkbrit]

It's almost hard to find a 4.6 that does NOT tap to some extent.....my 04 has had a very light tap since I bought it in 2005 with 14K on it...now has 70K but is fine.

ALWAYS use 10:40W oil....I prefer non-synthetic and change it regularly....every 5000 miles.

 

[ERover82]

I saw a good looking D2 approaching from down the street a few weeks ago, but as it passed I cringed at the loud obvious tapping. This was the first time hearing it and made me glad I got a D1 before I knew better.