Cbr600rr rattle when starting

Noises when starting SLK 230K Starter defective?

Hello everybody,

Unfortunately, my SLK built in 97 makes very unhealthy noises when starting.

I suspect the starter is defective.

Unfortunately, I don't know my way around very well and I hope you could help me or at least have an idea.

Attached is a video of the startup process.

As soon as the engine is running, it runs relatively stable and there are actually no problems when driving. The car "wobbles" a bit when idling.

I'm interested in your answers !

Similar issues
21 answers

For me, the noise comes from one of the ancillary units that the belt drives. But you should be able to localize that.

Yeah, it would be worth a swap. If there is nothing on the aggregates, but they could also be heard when idling. Motor actually ditto. Actually, they tend to run if defective, but I would replace it without much experimentation. But belt down and start it doesn't do any harm.

Almost all of them wobble, but many have been driving around with the original service parts for 20 years and then wonder. But you have to know that and act ... coils, candles, Lmm, probe etc ..

Side note: Especially with the r170 there are always people who proudly announce that they have only done the oil change for ten years and no other repairs were necessary ... or at the colorful flag dealer :-)).

Firstly, thank you for your replies.

I tried it out a little more and luckily I can start the engine relatively reliably.

Sometimes the noise does not come at all or only for a short time!

Could it be that the servomotor for the drive pinion of the starter does not "snap back" at the right time and is therefore somehow rotated with it?

The starter pinion will probably be defective on one or more teeth (burr or similar) so that it cannot - as actually intended - mesh with the ring gear. It then works again on the healthy teeth ... hope it's understandable what is meant.

Remove starter, check function and - depending on the findings - either repair or replace ... if possible before the ring gear is damaged.

Quote:

@ jw61 wrote on September 6, 2020 at 10:45:35 p.m .:

The starter pinion will probably be defective on one or more teeth (burr or similar) so that it cannot - as actually intended - mesh with the ring gear. It then works again on the healthy teeth ... hope it's understandable what is meant.

Remove starter, check function and - depending on the findings - either repair or replace ... if possible before the ring gear is damaged.

I hope it is the starter. What would be your next guess?

I let a colleague start and stood in front of the bonnet to be able to locate it and it now sounded less like it was coming from the underside of the block ...

I have also noticed that it happens less when the engine is warm.

I drove for about an hour, then parked it and started again immediately -> starts quite normally. Could it have something to do with the distribution of oil in the engine?

Belt down, start, listen. If the noise is still there, change the starter ... Philosophizing doesn't solve any problems.

Quote:

@ Killroy913 wrote on Sept. 07, 2020 at 4:11:31 am:

Could it have something to do with the distribution of oil in the engine?

Certainly not. I'm still guessing an auxiliary unit. There will be a dying camp. Belt down and then (!) Start for the first time. If it is then gone, turn the aggregates by hand. The rough running should be noticed.

Update of the findings:

This noise is really so loud that you can localize it with your ear.

I stood in front of it a few times when it started.

In my opinion, the noise clearly comes from the rear of the engine.

What I can't hear, however, is whether it's coming from below or above the block. While the sound is coming, there is a strong metallic vibration in the block. (I put my hand on at the start) it feels as if something is not lubricated well enough for a moment and thus scrapes / stutters / vibrates.

After a few engine starts, the noise comes out less frequently. The last 2 of the 5 or 6 starts sounded completely normal.

In addition, the starter has already been renewed!

I was able to take a picture with my mobile phone and it says "Remanufactured in Poland".

I have the uncomfortable feeling that the noise is coming from the direction of the cylinder head. Maybe something with a camshaft or even the cylinder raceway or a broken piston ring?

Hope and pray, lay on your hands and the discussion about it will definitely not get you any further.

It is perfectly clear that the cause of this noise is palpable and that your assumptions are wrong. Why don't you start systematically with troubleshooting?

Getting the drive belt down is a lot easier than quickly removing the starter. In addition, you can no longer check what is happening with the starter removed.

Quote:

@ Ha-Pe-85570 wrote on September 7, 2020 at 10:19:41 am:

Hope and pray, lay on your hands and the discussion about it will definitely not get you any further.

It is perfectly clear that the cause of this noise is palpable and that your assumptions are wrong. Why don't you start systematically with troubleshooting?

Getting the drive belt down is a lot easier than quickly removing the starter. In addition, you can no longer check what is happening with the starter removed.

Fair point.

Unfortunately, I don't have the technical details and sufficient knowledge to pull the belts down, let alone put them back on properly. I've only had the car a few days and don't know my way around yet.

I'll go to a workshop and have someone evaluate the noise.

Quote:

@MxD wrote on September 7th, 2020 at 11:35:12 am:

And then why the thread?

Is it normal that this is how you are approached here when you are simply looking for help?

I was hoping that someone would know the problem and that it might be something smaller than what I can do myself.

The car is parked in a public parking lot on the street in the city center. My options are therefore quite limited.

Didn't know that you can apparently only speak out if you already have 10 years of screwdriving experience.