tapping/clicking noise

[Wantacosmosm3]

My friend's e36 3 series makes a tapping/clicking noise whenever he starts it up. It stops after a second or so, anyone know what it could be?

[Ferris]

That's really vague... So where is the noise coming from? Does it sound like a relay or the engine? What oil weight?

[Wantacosmosm3]

yeah i know it's vague, i thought it was the lifters tapping but that's not it. It's coming from the engine.

[beeze]

Waterpump? You may want go to the front of the engine and listen for it. You can also wiggle the fan blade to see if it is sloppy. If it is sloppy, then the pump is going. Tell us when you fix it, so when people search they can get answers too.

[NegativeCambre]

I'd still say its lifters tapping... check his oil.. it may be low.

Does it rise and fall with increased revs?

And explain this statement a bit more: "thought it was the lifters tapping but that's not it. It's coming from the engine."

The lifters are in the engine, righto?

Steve

[Wantacosmosm3]

Originally posted by StevenRyan
I'd still say its lifters tapping... check his oil.. it may be low.

Does it rise and fall with increased revs?

And explain this statement a bit more: "thought it was the lifters tapping but that's not it. It's coming from the engine."

The lifters are in the engine, righto?

Steve

It doesn't happene when he revs, i was just seperating my thoughts. It might be, but i really doubt it it only does it on start up for a second then goes away. I won't see him till monday so i will tell you guys then.

[rockfish66]

This is the "universal BMW tapping" that seems to happen to every M50 motor and several of the others. There have been dozens of suspected causes and fixes.

It seems to be some sort of low oil pressure situation right on start-up. I find it worst when the engine is started hot (like betewenn autox runs) I guess because the oil is thinner when hot.

Most people I've talked to say just keep the oil topped up, and maybe even a little overfilled. That seems to have worked for me.

It's really embarrasing, though, to start your car in a parking lot and sound like a 73 Chrysler!

[NegativeCambre]

The reason it is happening between autocross runs is not so much that the oil is supper hot, but because during hard acceleration and fast sweepers, all the oil in the sump gets pushed to one side of the pan, making it so the pump can't get to it, and starving the valvetrain of oil. When the valvetrain dries out, bam, you get the lifter noise... that simple. It takes a moment or two to get the oil back up there...

The quick fix is the overfill by a quart method, a more expensive, eleagant and ultimately more effective route is to get your oil pan retrofitted by Turner's oil pan baffle kit. Not terrible expensive, but requires welding into the pan, which means a PITA oil pan removal (read: messy).

Right now I'm running the overfill method.

Steve

Originally posted by rockfish66
This is the "universal BMW tapping" that seems to happen to every M50 motor and several of the others. There have been dozens of suspected causes and fixes.

It seems to be some sort of low oil pressure situation right on start-up. I find it worst when the engine is started hot (like betewenn autox runs) I guess because the oil is thinner when hot.

Most people I've talked to say just keep the oil topped up, and maybe even a little overfilled. That seems to have worked for me.

It's really embarrasing, though, to start your car in a parking lot and sound like a 73 Chrysler!

[rockfish66]

Thanks Steve. I've heard seveal people mention the overfill fix.

I'll start using the "extra quart" method at this weekend's autox!

[NegativeCambre]

Yeah no problem... it is embarrassing sitting in the grid at your car is going TAP TAP TAP TAP TAP TAP TAP TAP. The bimmer guys usually know whats going on thoug... aha

Steve