[autosleek]

I did an oil change and after that when I started the car a loud knocking sound happened. its coming below from the oil pan but you can also here it above. I,ve used a hose but nothing came out from the top of the engine. it all came from the bottom were the oil pan is located. what could this be??? my worry is might be the connecting rod bearing. but why???it was running very good before I made the oil change.

 

[Uboater]

You can have a knock if your oil pump is slow to pickup oil or your new oil is lower in viscosity . A true test is with a warm engine , accelerate to 3 / 5 K rpm and left off the gas abruptly . It will knock with worn rod brgs. , harder to detect on smaller engines.

If it was a few knocks on start up I wouldn't worry .

 

[MiguelXJ]

What type of oil did you use?

 

[mountainredneck]

i agree with uboater on the start up ticking. wifes 260e does this in the morning. viscosity should not have made it knock unless you put like 5w- in it. even then i doubt it would knock. what do you mean by the hose thing?

 

[autosleek]

I used 5-30 valvoline and the knock does not go away. and its loud...really loud. you can hear it coming from the bottom were the oil pan is. could it be a busted bearing? but it was running so quit before I did a oil change. so confused and scared. I also used the hose as a stetoscope to determine were the noise is coming from.

 

[mountainredneck]

sounds like you better have it checked out by a pro. whats your oil pressure? when started up after oil change, did it start immediatley?

 

[Uboater]

Autosleek how long have you had this car .

Did you change the filter as well ?,, do you get a Quick needle jump on the oil pressure when starting or is it slow 4 -5 seconds before it shows pressure ?. Its strange for a brg. to die in a short time / overnight . Try a straight 40 weight oil see if its better .

Your sure its not a stuck valve or lifter iissue . No other causes - low water - overheated - over speed RPM - long climbs .

Could be a headgasket .

 

[autosleek]

i had the car for a year and no abuse use on it. the oil pressure is ok and the idling is fine its just that hard knocking sound. I would probably have it towed to my mechanic and have him check it. he says its probably one of the connecting rod bearings went out. so sad for me. also new oil filter fram. right now just dont have any idea why this thing happened. was working so fine before the oil change then after the oil change this happened.

 

[augapfel]

Fram!?!? Junk. Use an OE supplier filter tha has a good check valve to prevent drainback. I'm not saying that the filter caused the problem but your description does not sound good. Do not run the car since once the crank pin is scarred the engine must come out. If a bearing spun and the crank isn't scarred the fix will be much, much cheaper.

When I installed the 3L engine in my 260E I pulled the head and had it redone. I asked a couple of machine shops about replacing the rings and bearings while the engine was out and both said the same thing -- the bottom end of the M103 should be good for 250k miles unless the engine was run low on oil or severely overheated. Almost 30k miles later and the engine is running great.

My sympathies if the engine spun a bearing.

 

[Jackd]

A 103 engine rarely, if ever, has a problem with the engine bottom, even at insane mileage.

You said:
A FRAM filter with 5W30 engine oil?

Wrong filter, wrong grade of oil.... you're not helping your engine with that kind of a mix.

 

[autosleek]

i've bought the car from a friend of mine who is a mercedes benz mechanic...the history of this car was he changed the engine surplus and he had the head done but not the bottom. he also used 5-30 since I am located here in california. he said it maybe the connecting rod bearing might had just gave way...he does not know how many miles was in that surplus engine. ive also used the car for 1 year. the reason why I got the fram filter was I needed to change the oil on a sunday and there wasn't any dealer open at that time. my friend also told me that even if I used the fram oil filter...it would not make the engine knock right away...even if I also used 5-30. it just so happened that it really gave way.

would you guys know maybe how much it would run me for connecting rod bearing overhauling gasket and what ever i need for the bootom fixed...maybe include the piston ring also?

right know I will have to have the car towed to his shop to be inspected...

 

[Uboater]

One guys posted he could remove the oil pan and install rod bearing , with the engine in the car. I forget if it was a 103 or 104 engine , that could be a quick fix to keep you running .
If it uses oil perhaps rebuilt engine would be best , they are not to pricey and my end up cheaper than the local mechs labor to just get a ring - rod - head gasket fix.

 

[mrhills0146]

I am mystified as to the nature of your problem, but this I do know. There is NO WAY that simply using a Fram oil filter would cause what you are experiencing.

I've run several hundred thousand miles in various gasoline and Diesel powered Mercedes and used everything from Mahle to Napa Gold to Fram to Purolator oil filters with no adverse effects. Indeed, there is no discernable difference from filter to filter - I change the oil regularly as I subject my vehicles to lots of stop-and-go driving in a hot climate.

 

[autosleek]

exactly! that is why even my mechanic is so mystified also with this problem. changing to one filter to another will not make your engine knock right away. I would know when I bring the car to my mechanic and see what really went wrong. damn!

 

[curlytom]

I’m probably barking up the wrong tree here because they’re totally different engines, but here it goes…I have a Duramax diesel truck that simply does not like K&N oil filters. Whenever I put a K&N the “Low Oil Pressure” warning light comes on intermittently, then I change back to either an OE oil filter or Mobil oil filter and the problem goes away. I’ve tried this several times simply because I bought a case of the K&N and I get the same results.
So, I guess my point is, that it is possible for the filter to cause your problems.
Have you tried changing your filter to a different brand?

 

[Yal]

I wouldn't touch a Fram filter if someone gave me a box of them free. I think there was an ongoing problem with the bearings in the engine but the Fram filter coupled with the 5w30 oil took it the rest of the way Hope you hear some good news from your mechanic!

 

[mrhills0146]

I wouldn't touch a Fram filter if someone gave me a box of them free. I think there was an ongoing problem with the bearings in the engine but the Fram filter coupled with the 5w30 oil took it the rest of the way Hope you hear some good news from your mechanic!

Not a chance. There is no way that the simple act of using an arguably lower-quality filter or the incorrect viscosity of oil will make the motor knock. No way, no how.

A knocking motor either has low or no oil pressure or is running hot. Either one is a serious problem that likely existed well before the most recent oil change.

I just don't buy the filter reasoning.

 

[Uboater]

I think the decoding of the statement below , will lead to an answer ??

I,ve used a hose but nothing came out from the top of the engine. it all came from the bottom were the oil pan is located.

WTF

 

[Yal]

Not a chance. There is no way that the simple act of using an arguably lower-quality filter or the incorrect viscosity of oil will make the motor knock. No way, no how.

A knocking motor either has low or no oil pressure or is running hot. Either one is a serious problem that likely existed well before the most recent oil change.

I just don't buy the filter reasoning.

If you read my statement I said there was probably something wrong to begin with. This engine had issues before the oil change. The oil change just exposed it. Relax.

 

[autosleek]

I think the decoding of the statement below , will lead to an answer ??

I,ve used a hose but nothing came out from the top of the engine. it all came from the bottom were the oil pan is located.

WTF

if you read clearly it means I've used a hose to listen to were the location of the knocking sound is coming from either the top or the bottom of the engine. so iif its coming from the bottom it could have been one of the bearings.