8 replies to this topic

[MIJ]

Just wondered if this is considered normal. I can fire up my car and it will run fine with very minimal tappet noise, then after about a minute of running it starts to tap quite loudly and continue for a couple of minutes until it disappears again and the engine runs with minimal tappet noise afterwards. I'm concerned it could be doing damage and confused as to why it taps loudly like this after initial start up of abiut a minute.
Any ideas?

[blacktulip]

Have you checked your tappet clearances?

[TheFabMini]

How’s your oil pressure? Could be a lack of oil getting pumped up to the rockers until it’s warmed and thinned a bit?

[Rorf]

When last was the engine oil and filter changed?

[MIJ]

The tappets were checked only 500 miles ago, and oil and filter changed at same time. The car sits outside so like @chrisruffell has said could it be the oil is too thick to get to the top initially? Oil pressure sits at a nice 75 and gets there fairly quickly after start up.
Just worried it's causing damage for this few minutes if no oil is getting to them

[mini13]

the rockers are notr really "pressure fed" as such, they get a squirt every other engine rotation via a groove in the timing chain end cam gournel & bearing. this is enough to lube the bushes.

 

I woulld pop the rocker cover off, and check it isnt dry in there, and aslso see if you can slide a rocer to one side to see if the shaft looks worn, you can probably back one of the adjusters off enough to disengage it from the pusjh rod and check this, also give the rocker a wiggle to see if its particuarly wobbly on the shaft.

 

the Bushes are bronze so last fairly well so you can nrmally just swap a new shaft in.

[AP2020]

the rockers are notr really "pressure fed" as such, they get a squirt every other engine rotation via a groove in the timing chain end cam gournel & bearing. this is enough to lube the bushes.

 

I woulld pop the rocker cover off, and check it isnt dry in there, and aslso see if you can slide a rocer to one side to see if the shaft looks worn, you can probably back one of the adjusters off enough to disengage it from the pusjh rod and check this, also give the rocker a wiggle to see if its particuarly wobbly on the shaft.

 

the Bushes are bronze so last fairly well so you can nrmally just swap a new shaft in.

 

The camshaft has a groove at that end so oil flow to the rockers is constant due to pressure via the pump.

 

Not all rockers have bronze bushes, the later sintered type don't whilst all others do.

[AP2020]

Just wondered if this is considered normal. I can fire up my car and it will run fine with very minimal tappet noise, then after about a minute of running it starts to tap quite loudly and continue for a couple of minutes until it disappears again and the engine runs with minimal tappet noise afterwards. I'm concerned it could be doing damage and confused as to why it taps loudly like this after initial start up of abiut a minute.
Any ideas?

 

I suspect what you have is on start up there is enough oil at the rockers for the first minute... then it drys up a little giving you the rattle until the "new" oil pressure and flow catches up where it stops rattling...  as above look at oil & filter change and the clearance between rocker and shaft

[mini13]

What's that longitudinal groove in the cam bearing journel for then?