Hi Folks,

When starting the car, I heard a rattling noise for a few seconds and it goes away when the oil pressure goes up. This happened only twice so far when the car sat overnight. Last night, I heard the same noise when I turned off the motor and this only happened once.

For the engine noise, is this the timing chain? Is the first step to change the timing chain tensioner to see if that fixes the problem?

Thanks, Clive

__________________
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200 75 W115 (Mom's)
190e 90 2.6 W201
E320 95 Wagon W124
72 BMW 3.0 CSI

The M103 timing chain is very durable.
http://www.peachparts.com/shopforum/tech-help/120256-original-timing-chain-guides-record-mileage.html
What is your mileage and what is your oil consumption>?
My 88 300CE M103 taps once in a while when I start for a few seconds. I consider that par for the course for a 27 year old car with only 144,000 miles. I think it's more likely from the top end, not the chain.
Do you know if your valve stem seals and guides have ever been replaced? They won't last forever on a 103.

If the oil pressure takes some time to go to maximum after you've started the engine after it has been stopped for a while then it is likely that the oil filter return valve is duff. Oil could be draining out of the filter into the sump - it then takes a bit of time to get the filter filled when you start the engine again and the top end of the engine rattles because it is being starved of oil...

...if it is this - solution is to put on a good quality oil filter.

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

The car has 270K+ miles and running. I do not have any prior history prior to purchase. I can only assume that the I still have the original timing chain and tensioner.

When I start the car, it takes about 2-3 seconds for the oil pressure gauge to reach 3 bars and I use Knecht oil filters. Today, I could hear the rattle noise faintly until the oil pressure builds up. Anything else, I can do to remedy the situation besides checking the guides and replacing the seals if necessary.

__________________
---------------------
200 75 W115 (Mom's)
190e 90 2.6 W201
E320 95 Wagon W124
72 BMW 3.0 CSI

cleavster:

1) The area that is least likely to be a source of low oil pressure startup noise is the valve guides and valve stem seals. Why? They are not supplied with pressurized oil.

2) The areas that can be a source of noise are, a: the timing chain, before the hydraulic tensioner receives oil pressure, b: the hydraulic compensators [aka, "lifters"] in the rocker arms. When the engine is stopped, any valve that is off its seat will put spring force on the corresponding rocker and the compensator in the rocker tip. The compensator can leak its oil, and when the engine is restarted there will be clearance between the rocker tip (and compensator) and the tip of the valve. Until oil pressure reduces the clearance to zero there will be audible clicking.

Excluded at this time are connecting rod and main bearings; they can also make noise on startup, but the sound is much heavier than valve noise.

Thank you for all your replies. I'll start by checking the timing chain stretch on the engine. Is the easiest way to check for stretch is to use a timing light and if it is off by 5 deg on M103 then it's time to replace it? Is this correct?

__________________
---------------------
200 75 W115 (Mom's)
190e 90 2.6 W201
E320 95 Wagon W124
72 BMW 3.0 CSI

NO. Timing chain & sprocket wear (incorrectly called "stretch") is checked statically.

Chain & sprocket wear is not in itself a cause of the subject noise; a hydraulic tensioner that relaxes can be a cause of the noise.

From what I'm reading I should do the following:

(1) Remove valve cover and check for any loose lifters. If any, change them. Do I change them all or just the ones that are loose?
(2) Check Timing Chain - how do you properly check the timing chain? If not in spec, go ahead and replace, with new guides.
(3) Replace timing chain hydraulic tensioner. Can you reuse a new tensioner or is this a one shot deal?

Is this correct?

__________________
---------------------
200 75 W115 (Mom's)
190e 90 2.6 W201
E320 95 Wagon W124
72 BMW 3.0 CSI

From cold start the oil filter is allways empty .If you have ever changed oil on the M103 engine this is normal .Every filtter i have removed as been void of oil [from cold that is ]

I'll try and dig out some pictures for you showing the valves in the filter canister.

Next time you change one you can plug a screwdriver in the end of it and see the oil coming out if you want...

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!