Lifter Tick or Fuel Knock? *VIDEO*
 

Hey guys I've noticed a loud tick that has become increasingly consistent over the past few weeks. It occurs whether the engine is hot or cold and proportionally increases with the engines RPM. I'm beginning to think the noise is from a sticky lifter as opposed to a fuel knock on an injector. I was hoping someone with a better trained ear could tell me.

Some background info on the car:
1987 300d om603 turbo 118,xxx
2nd owner (owned for about 6 months)
service records indicate fuel injectors are original
glow plugs replaced in 1999 roughly 20k miles ago (it wasn't driven much the last decade)

Here is the link to the video of my engine ticking: 1987 W124 300d Lifter Tick - YouTube

NOTE: the engine is currently at operating temperature

Any thoughts or opinions are greatly appreciated!

It has the frequency of lifter tick. To be sure, disconnect the belt tensioner damper at the head and see if the noise persists.

Sixto
87 300D

Lifter noise. Oil change may help. I just switched to Mobil 1 thinking it could help stop the noise better than regular oil.

Sounds a lot like mine right now...

Quick run from cold start of 87 300D - YouTube

FYI
 

Gentelmen, both of your engines are running below minimum RPM at idle..

Either:
* The throttle cable needs adjustment.
* The BRACKET is bent down where your throttle cable screw adjustment attaches.
* The Electronic idle speed control has issues. Doubtful from the sound.

Note: You have e-mail................

"ngarover", You have at least two failing glow plugs, and serpentine belt tensioner / shock failure noise.

.

Gotta love these thread starting ninjas...
 

BEULLER?

BEULLER!?!?!?!?

Chop chop, inquiring minds wanna know.

MBZ123

Only took me a year and half to get back to you guys lol. A new record. My apologies.

Just as many of you suggested, the noise was a sticky lifter. I ended up draining some oil and adding a quart or so of fresh transmission fluid to the crankcase. Drove roughly 20 miles on some back roads in a low gear and voila no more tick. I changed the oil/filter as well afterwards using mobil delvac.

This was all in vain of course, as someone hit me a few months later putting the car out of commission. I parted the car and sold the motor to a gentleman for his w123.

In the time since, I've bought and just recently sold another 87' 300d. I switched that motor to rotella t6 and it made a noticeable improvement during cold weather cranking. It also made a noticeable contribution to the surface of the parking lot at my apartment complex lol. I recommend you plan for new seals if making the switch.

Not to beat a dead horse but while we're on the topic of engine ticks and tacks, I've gotten great results running diesel purge through the pickup and return lines. It really smooths out the idle on a neglected motor. I run a can on each new (to me) diesel I get. B20 also acts as a good solvent and is worth running every now and again IMO.

Sorry for taking so long to reply. Better late than never I suppose.

A new set of lifters costs $120 and 2 hours of DIY labor.

Never priced it out before. I figured it would be more expensive than that.
I'll keep that in mind if I run into future lifter issues. Heading over to VA this weekend to look at a 300td.

Both the price of new lifters and using ATF is relevant to my interests. How does ATF clear lifter knock?