M70 ticking noise.

[Ericks2002]

Started the car up this morning to and drove it around the block. When I got out I hear this knocking noise coming from around the passenger side distributor area. It was fairly cold for where I live. About 50 degrees F. I took the distributor apart in case the rotor came loose but it was fine. What does this sound like to you guys? The noise went away for a second and came back at one point. Lifter tick? Timing chain issue?


https://youtu.be/LznwPj18ntI

[Ericks2002]

Started the car up again and it sounds like it’s coming from the oil pan. What are the odds that I spun a rod bearing at 80k miles....

[Ericks2002]

False alarm. Turns out it was the AC compressor. I flushed everything and put the correct amount of oil when I converted to r134 last week. I guess I got a faulty Denso unit because the noise goes away when I turn the AC on

[ChrisFuture8]

Ericks2002, it may be a false alarm in your case this time but that ticking noise is real...well, at least in my case. My driver's side does make that fast tick, tick, tick sound especially after I have driven the car for extended distance. It is not the valves ticking due to low oil. It's somewhere by the distributor cap or the ignition coil. It just happened to me last night coming from a 5 hours drive. I think it's electrical related due to excess heat under the hood.
I pulled into a gas station and with the engine still running, I got out of the car and hear the ticking...popped the hood and traced the sound to the distributor/ignition coil area. I turned off the motor, let it sit for a couple minutes, unplugged the ignition coil plug and plugged it back, restarted the motor and the clicking noise stop.

Not sure if anyone else experienced this before. I have had this happened 3 times already. This time, the engine in the car has just been replaced with one under 80K miles so I know it's not the motor as I had replaced 90% of the gaskets on the motor and went through everything already. All of the electronics and cables are pretty close to new.

[Ericks2002]

Took the belt off and ran the car. Still sounds great. Felt for play in the Ac compressor didn’t feel any. Felt for play in the water pump and there was some. Starting to think it’s the water pump. Cant seem to find any good replacements though.

[TxGR8White]

That ticking noise could be coming from a faulty or cracked rotor. It is actually the arcing to the distributor base that you are hearing...

[Ericks2002]

The noise went away when I removed the belt or when the AC compressor is turned on so I’m thinking it’s something on the AC belt pulley drive. Either the compressor or the water pump.

The rotors and caps were replaced recently by the previous owner of the car also.

[ChrisFuture8]

My rotor and cap has less than 10K miles as well (probably around 6K). It does this when the temp is really hot under the hood. Temp gauge is at 12 o'clock mark so not like the engine is overheating. It's a bit strange.

[shogun]

I once had such a noise on the compressor, it was the compressor shaft, too much wear on the surface where the pulley and clutch are, pulley was wobbling on the shaft,
https://www.bimmerforums.com/forum/s...mpressor+noise

[Ericks2002]

Interesting your noise happened when the compressor is turned on while mine was the opposite. I redid the belts and tensioners and the sound has gone away. I’m not sure why this fixed the problem. I noticed when removing the belt it was very difficult to get the belt off. the idle tensioner wasnt compressing. I had to completely remove the idle tensioner and the pulley to get the belt off. Everything went back on normally though.