Lifters Tap Tap Tap

[mac123yre]

My engine is rebuilt new bearings the lot but I did not change the lifters, I have now done this but still have a constant tappet type sound, it only happens when the engine is hot its ok when cold, there is no slop on the rockers and I can see nothing wrong, any one else had the same problem.

1988 350I

[HOTTY]

How bad is the noise, is it not just the injectors ?

Stephen

[SEvans]

What oil are you using?

[adam quantrill]

Is that a new cam or not?

[pwd95]

My understanding of this is......a new cam will destroy old lifters because of the microscopic rough edges of the new cam. Equally new lifters will destroy an old cam for the same reason.
They both have to be new at the same time, with proper lubricant to run each other in as per procedure,,,,,20 mins @ 2k rpm.
I stand to be corrected.

[mac123yre]

It’s a light tap new lifters now and new cam, the sound seems to be from the plenum, totaly foxed, if any of the wedge experts from the north let me know and I will bring it round and get your opinion.

[HOTTY]

HOTTY said:

How bad is the noise, is it not just the injectors ?

Stephen

[adam quantrill]

Don't run the engine, turn on the ignition, then swiftly rotate the throttle by hand at the engine, you should hear a click each time you open the throttle. This click is the injector click and is quite normal.

Other things that can cause ticking are loose exhaust manifold bolts, a blown exhaust manifold gasket, a hole in the manifold, or a trumpet in the plenum being loose and wobbling about. For the first three run the engine from cold and feel around the exhaust before it gets too hot!

[mac123yre]

will have a go and let you know how it goes

[ed_crouch]

I used to have a wobbly trumpet. Sounded awfully like a buggered lifter, but upon plenum removal I was greeted with the welcome sight of a trumpet that had shaken out of its base and was rattling about. Din' alf' sound like a knackered lifter, I tell you!

[TOPTON]

adam quantrill said:

Other things that can cause ticking are loose exhaust manifold bolts, a blown exhaust manifold gasket, a hole in the manifold, For these three run the engine from cold and feel around the exhaust before it gets too hot!

Or even try squirting wd over the manifold before it gets too hot. I had this tapping with mine, but when new manifold gaskets were fitted, all was good

[TVRleigh_BBWR]

You said new cam and lifters was these changed at the same time, and run-in correctly, plus did you check the preload.